The leaves are changing and starting to fall – and if you haven’t noticed yet, they’re not the only thing falling out of trees this time of year. This is the season when trees drop fruit and nuts that are edible to both you and the squirrels you may have to contend with if you take on a foraging adventure. From acorns to persimmons, this is a time of year when native bounty can still be found, even when gardens are being pulled up and put into the compost pile. With a little knowledge and some safety precautions, it is possible to find a significant amount of tasty and nutritious nuts around the wooded areas of Richmond. Just be careful – be a sustainable forager, as the native wildlife can’t run to the grocery store. They need these fruits to make it through the dark and cold winter.
The most obvious and ubiquitous nut that can be found throughout Richmond is the plentiful and often-hated acorn. The number of complaints we hear about acorns falling on roofs and cars, causing tripping hazards, and staining patios is quite high this year and for good reason. Acorns are everywhere! Acorns are the seed of Oaks and can range greatly in size and appearance, with some being the size of a finger nail and others almost the size of a ping pong ball. Beneath their fibrous hull lays a future towering Oak or a decent amount of nutrition if processed correctly.
Acorns in their raw state can be poisonous to humans, as they contain varying amounts of Tannins, which are protective compounds created by trees to limit damage to their seeds. Most people are most aware of tannins in red wine, which come from both the grapes themselves as well as the Oak barrels they are aged in. They are the compounds that make the wine a bit astringent and bitter, in a good way. When you have an excess of tannins, the result is a wholly inedible nut that just tastes plain bad. This can easily be solved by dehulling the acorn and soaking the nut meat in water to draw out the tannins. After proper processing, acorns are not eaten whole like most nuts. They are typically ground into a coarse flour that can then be used to make items such as pancakes and somewhat-bland crackers.
There are many websites online that can explain how to properly process acorn meat, but be sure to follow good instructions to avoid possible illness from excess tannins. Also note that while acorns are exceptionally plentiful, they are not the most nutrition-dense nut. Plus, from most accounts, they don’t taste like much when processed and cooked. While it may be a fun experiment, don’t expect exciting culinary results.
The next tree that produces edible nuts in large quantities around Richmond is the Hickory. All species in the Genus Carya produce nuts, and most of them are edible, with one being a highly sought-after nut during the holiday season. First, the tree that most people think of as a ‘Hickory’ will fall into several different species, including the Shagbark Hickory, Shellback Hickory, Mockernut Hickory, Pignut Hickory, and Bitternut Hickory. It is important to be able to properly identify the species, as not all produce palatable nuts, with Pignut and Bitternut both being species that produce bitter meat. This is one of the reasons many people do not harvest these nuts, as identification can sometimes be hard. It should also be noted that many of the edible species simply don’t have enough meat to make it useful as a food source for humans. The one exception to this is the Pecan.
Most people do not know that a Pecan is actually a type of Hickory, but that’s easy to understand, as the nuts do look somewhat different. We all know the Pecan for its appearance during the holidays in many baked goods and candies. There are multiple cultivars of the Pecan, but they are all in the genus, Carya. This classification makes it the most recognizable hickory nut that can be found in the Richmond area. Do note that after many years in the Richmond area, I have only found viable Pecan fruit on trees in the Petersburg/Colonial Heights areas due to their slightly southern location. While Pecan trees grow well through the region, it seems that only trees south of the Richmond Metro area are capable of producing viable nuts.
The final easily-found nut in the area comes from the Black Walnut tree, which produces large, edible nuts that have a very robust “walnut flavor.” The nuts that are typically thought of as walnuts come from the English Walnut tree, which produces large, mild-flavored flesh. Some nut producers even add small amounts of Black Walnut nut oil to their English Walnut flesh to produce a stronger walnut flavor. This strong flavor is one of the main reasons that Black Walnuts are not harvested in large quantities for their meat. It is also because the hull of a Black Walnut is extremely hard, and obtaining the flesh from the deeply-lobed nuts can be quite difficult. In areas where Black Walnuts are prolific trees, people collect the nuts to make confectioneries out of the meat, including Black Walnut cake and Black Walnut taffy. The use of these nuts in sweets allows the strong flavor of the meat to be tempered a bit, making for a very tasty treat.
While there are other edible items including mushrooms, Persimmons, other lesser sought-after tree nuts, it is good to start with the easily-attainable and relatively safe nuts listed above. With a little bit of knowledge and some elbow grease to get after the meat, it is possible to find a tiny banquet laying in your backyard. Do remember to make sure that your identification is spot-on, and that you follow all precautions to make sure the nuts are safe to eat! But most importantly, remember to leave enough for the animals that rely on this natural bounty.
It has been a pretty rough summer, with nearly intolerable heat that seemed like it would never end. But with cooler morning temperatures and less humidity, it feels like fall is right around the corner. While fall usually has people thinking of pumpkin spice everything and fall festivals, arborists and horticulturalists start thinking about tree planting. If you haven’t seen the banners outside of your local nursery, or the bumper sticker on your landscaper’s trucks, then I will let you in on a little secret: fall is for planting!
After a long, cold winter, most people crawl out from under their blanket cocoons in March, eager to fill their yards and landscape beds with beautiful, new plants to welcome warm weather and beautify their properties. It is easy to understand why this is a natural reaction, as spring is a time for rebirth and new life – so why wouldn’t it be the best time to put new plants in the ground?
It all comes down to roots. Without a healthy and well-established root system, a plant cannot support itself structurally, or search for water when the heat of summer starts pumping. Plants installed in the spring need months of time to acclimate to their new home and LOTS of water to ensure that roots do not dry out and die back. Constant watering creates a lot of work, which can easily be forgotten as summer activities pull you from your diligent watering schedule. Good news though – fall weather is perfect for root growth, and, most of the time, Mother Nature will take care of most of the watering for you!
Roots of woody plants, trees, and shrubs grow best when soil temperatures range between 65 to 75 degrees Fahrenheit. These are common soil temperatures in the spring and fall, but the main difference is what comes after those seasons. Fall planting allows for good root growth with cooler soil temperatures and (usually) adequate rain to reduce the amount of supplemental watering needed. While root growth does decline and stop as winter sets in, the plants go into dormancy and stop all growth, which greatly limits their water needs over the colder winter months. When spring finally arrives, the plants come out of dormancy and have yet another season of favorable weather to grow stronger roots before the heat begins to stress the plants.
With fall being the best time to install new plants, the next step is to make sure that you plant the trees correctly. There are many guides online regarding proper hole sizing, backfill material, and depth, which can give you good guidelines. Nearly all of these recommend digging a whole twice the diameter of the root ball and backfilling with original soil from the hole. While this is great in a perfect world, I will be honest that I have never once planted a tree to the specifications provided in these guidelines, as I am simply too lazy to dig such a big hole. More important than hole size is the dynamics of the hole where the tree is being planted.
When using an auger or even a shovel to dig a hole, the sides of the hole can become very smooth and glazed. This creates a transition that tree roots do not want to grow through, so the tree will grow roots to the edge of the hole and begin circling in the planting hole. This greatly limits root expansion, and is very similar to planting the tree in a pot in the ground. The easiest way to avoid this issue is to use a shovel to break up any smooth or glazed walls of the planting hole, which allow the roots to spread into the existing soil beyond the planting hole. Secondly, it is not recommended to amend this soil in any manner with compost or fertilizer mixed into the soil. This again creates a rooting environment where roots only want to stay in the amended and aerated soil of the original planting hole, and will not venture out. Finally, never dig the hole deeper than the root mass of the tree, as settling soil over time will make the tree sink, and the root flare can become buried over time.
After the hot, dry summer we have been through, we have been seeing a significant number of trees succumb to the stresses of the season. It is important to help regenerate our urban forest with new trees and shrubs. Utilize the coming weather this fall to give your new trees and shrubs a leg-up by installing in the fall rather than spring.
The definition of an Arborist is a person who cares for woody trees, shrubs, and vines, but you will be hard pressed to find me caring for or even about many vines in the landscape. To me, almost any plant that vines and grows up trellises or trees is a problem that can best be solved by severing and killing the vine. This is because most of the vines we deal with in the Richmond landscape are invasive species that spread out of control, damage natural ecosystems, and often damage the plants they are growing up. Be it Wisteria, English Ivy, Poison Ivy, Trumpet Vine, Honeysuckle, or Oriental Bittersweet, I hate it with a passion. There as usual is always an exception to the rule and in this case, I actually love Virginia Creeper vines!
Virginia Creeper is a native vine that does all the things a good vine should while not causing the damage of most vines. Virginia Creeper is a non-invasive vine that climbs trees and structures, provides food for birds that spread its seeds, has a beautiful fall color, and does not overgrow its host plant. When compared to most other vines, Virginia Creeper is a bit of an anemic grower which means that it can take quite a while to fully grow up a tree and because of its low to moderate vigor, it will not overgrow the canopy of a tree or enshroud the stem with foliage which would otherwise hide possible defects.
Virginia Creeper can be easily confused with another native vine, Poison Ivy, as they have similar growth habits, leaf arrangement, fall color, and hairy vines. Due to this similarity, Virginia Creeper is often lumped together with Poison Ivy and is killed with herbicides when homeowners attempt to rid their property of Poison Ivy. There are several easy ways to tell the two apart; the easiest is the leaflet arrangement on the petioles of the leaf. Both vines have compound leaves which means that each petiole, or leaf stem, has multiple leaflets, unlike a simple leaf which has one leaf surface per petiole. Poison Ivy has three leaves per petiole which leads to the old adage “three leaves don’t touch me (or let it be).” Virginia Creeper has 5 similar shaped and sized leaflets per petiole, and the adage continues “leaves of five, let it thrive.”
The vine of Virginia Creeper also has a similar appearance to that of Poison Ivy as they both produce hair-like structures that help them attach to and hold onto surfaces. Poison Ivy has a much finer and denser amount of “hair” that fully envelops larger diameter vines and I always liken its appearance to that of teddy bear fur. Virginia Creeper has larger and fewer “hair” which usually does not fully envelop the vine and seems to hug and grab onto the surface a bit more.
While I can find a seemingly endless amount of reasons why I hate most vining plants, Virginia Creeper seems to offer a stark contrast. The beautiful orange and red fall color never fail to impress and the beneficial source of food for birds and other animals should be reason enough to allow this native and underappreciated vine to grow in your garden. Do know that the beautiful blueberries are toxic to humans and pets, but it is very unlikely that the fruit will be in an area that can be easily accessed.
Last week my colleague, James, suggested you take a bit more time to “look up” in your day-to-day activities to appreciate your surroundings and sometimes see a truly remarkable tree that you might otherwise overlook. I felt that it was only fitting to piggyback on James’ advice and hopefully urge you to look down a little more often as well when it comes to trees. Humans love trees for many reasons and almost all of those reasons are for the above-ground benefits trees provide for us. Be it shade, wind-blocking, beauty, or useful resources, most of the time we look from the ground up and don’t acknowledge how much of the tree we can’t actually see. From the interior of the tree to the roots spreading out from the tree, there is a significant portion of each tree that is very important to the health and stability of the tree that we can’t even see. So let’s look down for a moment!
I do sometimes wish I was Superman and had all of the superpowers that our heartland superhero has, but when it comes to my job, the most valuable power would be that of x-ray vision. The ability to see underground and inside of a tree would be a game-changer, allowing for unbelievably thorough structural evaluations that could catch big problems before they can become even bigger problems. Root and stem decay would be immediately identifiable and preventing tree failures would be a simple task. Alas, I am no superhero and I surely do not possess the skills needed to identify every tree hazard, but I do have one tool that goes a long way in determining potential issues and that is looking for and identifying mushrooms growing on and around the base of trees.
A common talking point when I am meeting with new clients is to keep an eye out for mushrooms growing on and/or around mature trees in their landscapes. Mushrooms can be an indicator of a much larger issue that is invisible to those without x-ray vision because the mushroom itself is only a small portion of the larger fungus body. The fungal body that we call a mushroom is actually just the fruiting body of the much larger organism that produces spores to help the fungus spread throughout its environment. This fruiting body can be ephemeral, popping up sometimes for no more than a week or two, which then withers and decays while the fungus itself is still happily feeding on the wood of the tree. By looking down a little more often, it is possible to catch these mushrooms before they disappear, allowing us to briefly glimpse inside of a tree.
Typically, if a mushroom is growing on the tree itself, it is an indicator that the tree is being parasitized by a fungus which is likely weakening the tree’s structure. If mushrooms appear to be clustered around the base of a tree or radiating outward from the tree linearly, it is likely the fungus is feeding on the roots or very base of the tree. All of these signs are often overlooked indicators that the tree may have structural deficiencies that could lead to the failure of the tree. Keeping an eye out for mushrooms gives a homeowner and an arborist the opportunity to catch unseen problems before they lead to a possible failure. As with everything in life, this is not always a hard and fast rule so identifying the mushroom species is especially important.
When mushrooms pop up around a tree, the best thing to do is take several photos of the mushroom or mushrooms to show their size and proximity to the tree. Singular small mushrooms of one species may be completely innocuous while the same from another species may be signs of a large issue. Once photos of the mushroom are obtained, the next best course of action is to reach out to an arborist to look at the mushroom on site. This allows for a detailed assessment of the fungus itself and the tree. When this can’t be accomplished in a timely manner, the next best option is to then remove the mushroom and photograph the underside of the fruiting body as the spore structures can be a very important tool for identifying the species of fungus. This should be done as a last resort as it usually requires removing the mushroom from the tree and breakdown begins almost immediately after it is severed from the rest of the fungal body. Also, note that removing the mushroom itself does little to help the tree as much of the fungus is still within the tree where it can continue to do damage.
The best time to “look down” is in the late spring and early summer after heavy rains and later summer to early fall when fall rains begin as the conditions at these times foster mushroom growth. Don’t panic when mushrooms do begin popping up but do take the time to acknowledge them and identify them as best as possible. By paying attention to these signs, it can be possible to catch otherwise invisible issues that could lead to the failure of a tree. Sadly, in most cases, it is not possible to treat wood decay fungi so identification is only useful in determining what should be done with the tree if decay has progressed too far. Keep an eye out this year and years to come as it could possibly save you and your property from damage.
Spring has sprung and with newly expanding foliage and warmer temperatures, the familiar sights, sounds, and smells of our desire to have a pest-free landscape are everywhere. Be it treatments to our lawns to make them dark green and weed-free to the whir of backpack blowers putting out clouds of mosquito control products, we are constantly surrounded by pesticides that are being applied in an attempt to fix a problem that may be occurring around us. While the vast majority of these applications are done in a safe and highly regulated manner, it does not always mean that there are no side effects to these treatments. These products and their applications are likely to pose very little threat to humans and the other vertebrates in the landscape but that is not the case when it comes to off-target invertebrates that share our landscapes.
Most pesticides are somewhat selective in what they control or kill but it is highly likely that no matter how precise a chemical is, insects and other invertebrates posing no harm to you or the landscape can be killed. While this is not too large of a problem as populations can bounce back relatively quickly, it does leave a void in the natural cycle of the landscape which allows for opportunistic and usually damaging insect populations to boom. As non-target and beneficial insects slowly recover and fill the void, it is often too late for nature control to begin as the pest population has a head start so damage begins to appear in the landscape. This often triggers a visual cue from the plants that damage is occurring and the cycle likely begins again with the need for additional treatment, once again causing a population crash amongst beneficials and pests alike.
Once a landscape becomes locked into a treatment cycle, it can be very hard to simply stop in the middle of a growing season so it is best to begin a new approach with a new growing season. I personally find myself in the conundrum of how to keep my vegetable garden and landscape healthy with limited pests and am taking the opportunity to try a new approach this year. I have always used organic insecticides but they are quite often broad-spectrum and kill far too many off-target insects so most of them are off my list as well this year. With a majorly diminished arsenal to keep my veggies healthy and productive, it seems that the addition of beneficial insects and mites will hopefully be the answer to my pest problems. Instead of killing indiscriminately, a properly selected beneficial can be living, breathing, seek-and-destroy predators that will only affect very selective pests.
A small microclimate in my landscape warmed enough this spring to cause a major Two Spotted Spider Mite outbreak with damage spreading quickly on the affected plants. Using a jeweler’s loop, it was possible to determine the exact species of spider mite which allowed for the selection of the correct predaceous mite to eat not only the damaging adults but also their eggs. When the outbreak is under control, the predaceous mites can simply move to a different location in search of another meal or will simply die off leaving no trace on the affected plants. This pinpoint accuracy allows for very selective pest control, almost eliminating off-target control, and boosting the native populations of beneficial insects on my property.
Nearly every year there is also an outbreak of cabbage worms and whiteflies on all of my brassicas which makes warm-season kale and collards impossible in my garden. I am hoping to change that this year with the introduction of convergent Lady Beetles (Ladybugs) and Trichogramma brassicae wasps which are specific predators of cabbage worms. The Lady Beetles are voracious feeds both in their larval and adult stages, eating nearly any soft-bodied insects they can find. While they are much less selective, it is of little concern as most soft-bodied insects in your landscape and garden are pests that damage plants. The Trichogramma wasp is the opposite as they lay their eggs only on caterpillars that damage Brassicas, which then hatch and parasitize the damaging caterpillar, eating it from the inside out!
A very damaging pest that has made quite a showing in Richmond over the past two to three years is the invasive Crape Myrtle Bark Scale. This soft-bodied scale insect appears to be the first pest in our region that can overrun and kill a Crape Myrtle. While this pest can be easily killed with many conventional and organic insecticides alike, I will be watching my five Crape Myrtles carefully for any signs of infestation, and when (not if) it appears, I will be purchasing Lady Beetles or Green Lacewings to help keep the population from growing out of control. They will help me keep the trees healthy and clean while I don’t have to worry about my neighbor’s honey bees that like to feed on my Crape Myrtles.
The hardest part of adding beneficial insects to your pest control routine is that it takes more forethought and planning than simply spraying a chemical. With beneficials being so selective in what they control, it is important to know and understand what type of pest you are trying to control. It is also important to ensure that beneficials are introduced before pest populations grow too large as they cannot deal with massive outbreaks. Finally, timing is key and many beneficials must be bought locally or overnight shipped and then released the same day to prevent death during storage.
If you are looking to utilize beneficial insects this year, they can easily be purchased online from growers and I had great success with Arbico Organics out of Arizona for my predaceous mite purchase. While they worked beautifully, I do cringe at my carbon footprint for the 2000 mites purchased as they were flown from Arizona to Richmond purely for my landscape. An even better way to help your garden and greatly reduce your carbon footprint is to buy locally as several different beneficial species can be purchased at Sneed’s Nursery in Bon Air. While these beneficials are likely still overnight shipped, by purchasing in larger quantities, nurseries like Sneed’s can massively reduce the carbon per insect as compared to my individual shipment. I look forward to inviting new guests to my landscape this year, even if it is only to push out other unwanted guests. With luck and some diligence on my part, I feel that I will be able to give my garden and landscape the care it deserves without sacrificing a healthy natural cycle around my home.
Mulch provides an idea habitat for artillery fungus | Photo by Kathie Hodge
With the warmer temperatures and budding trees, there is no doubt that spring has fully sprung in the Richmond area. With the arrival of spring, it is likely that many people will be out and about in their gardens cleaning up from the winter, putting new plants in the ground, and mulching landscape beds to keep plants healthy and reduce the need for weeding. While most know the many benefits of mulch, one commonly overlooked issue, Artillery Fungus, can be introduced to your property when installing many types of mulch. This common fungus is not pathogenic to plants or animals and even though innocuous in appearance, it can be quite troublesome to homeowners in the way it spreads its spores on the landscape.
Artillery Fungus, Sphaerobulus stellatus, is an interesting organism that feeds off of decaying plant material and is actually quite beneficial as a decomposer in the landscape, breaking down mulch and slowly releasing nutrients into the soil. If that was all this fungus did, it would be of little interest and most would never even know that it exists. It is the method of spore dissemination that makes this fungus extremely interesting and even problematic. The mature spores are ejected from the fungus using water pressure to fire a sticky spore mass towards the sunlight so that the fungus can spread as far as possible into new areas. You can see a slow-motion video of this action here: https://m.youtube.com/watch?v=T8OAmcUnm4g.
This is an amazing adaptation that allows the fungus to spread its spore over long distances but becomes a nuisance when the spores are fired towards light-colored objects on a property, such as your brand new white car or lightly colored siding. The light reflecting off of these items tricks the fungus into thinking that the area is an open sunny clearing, so spores are shot and stuck to the items rather than an intended target. While the spores are not dangerous, they are extremely sticky, and even scraping them off of the surface will likely still leave a small tar-like spot on the surface. After several years of growth on a landscape, houses and the like can easily end up looking like a splatter painting of small black dots all over the item. There are many tricks and tips online to remove the spores but know that it will be a chore and is not always successful.
While there is no good way to eliminate the fungus once it has established itself in the landscape, it is easy to prevent the introduction in the first place by choosing the correct mulch for your landscape. Any type of aged wood mulch is likely to introduce the fungus as mulch manufacturers and processors store groundwood in large piles to age and break down prior to application. These large piles are perfect breeding grounds for Artillery Fungus so nearly every batch of mulch will come with a fresh colony of the fungus. The use of non-aged mulch such as fresh wood chips, pine bark mulch, or pine tags will likely be free of the fungus because they have not been aged in bulk piles, preventing the development of the fungus prior to application.
If you have ever spoken to me in person about the health of your trees and shrubs, it is quite likely that I gave you my soapbox speech regarding the use of herbicides around trees and the danger some products can pose to your woody ornamentals. I personally use herbicides around my home in a judicious manner as I feel that if used properly, their benefits can outweigh their risks, but it becomes hard to know what to use, how much, when, and why. I approach all pesticides from a professional viewpoint as I have been a Registered Commercial Pesticide Applicator in Virginia for nearly fourteen years which allows for a deeper understanding of their usage. Most homeowners do not have this background and rely on product claims, Google searches, and advice from neighbors. While all of this can be better than nothing, it can also spread incorrect information that could lead to long term problems for you and your landscape.
The use of pesticides in general is a very polarizing subject so please understand that this is neither a promotion or denouncement of their use and should be taken only as advice if you choose to use them. It is also important to note that only the general category of herbicides will be discussed as insecticides and fungicides can be extremely selective in their efficacy and can also cause significant harm if used incorrectly. While some of this is also true with herbicides, they will be the focus as the chance for damage to your plants is much greater with misapplication than that of insecticides and fungicides. Finally, brand names will not be mentioned as most herbicides can be purchased under many brand names so chemical names will be the focus to ensure clarity.
First, it is important to know what an herbicide actually is. Herbicide specifically means it is a chemical that kills plants as “herb” is the prefix to denote herbaceous material and “cide” is the prefix that means to kill. This is why we have multiple pesticides (to kill pests) that can range from virucides, to bactericides, up to things like piscicides that are used for killing fish. It is important to remember that whatever pesticide is being used, it is designed to kill something and improper use can harm or even kill unintended targets.
No matter what herbicide you choose to use, remember to ALWAYS follow the instructions on the label attached to the container. The label with all of its warning and directions are actually legally binding and it is against the law to use a product in a way that is not listed. As an American male, I sometimes fall victim to the mindset that if a little is good, then a lot must be better and that seems to be the natural trend when it comes to most pesticides. If a product says to mix one ounce of chemical with one gallon of water, then it should be done exactly as directed. While it might seem that two ounces would work twice as well, it really won’t and it can actually do harm to off target plants. Even if you don’t cause unintended harm, it is simply wasting money as the products are designed to be effective at the labeled rate and stronger mixing just wastes money.
Always be sure to follow the instructions on what time of Personal Protective Equipment (PPE) to wear, which is almost always a minimum of closed toe shoes, long pants, long sleeves, chemical resistant gloves, and eye protection. Just because you can purchase these chemicals over the counter at nearly any store, does not mean that they are not dangerous if used incorrectly. Even though herbicides are designed to kill plants, they can still be dangerous if applied to the skin or accidentally ingested. They are still manufactured chemicals designed to kill so it is important to limit contact wherever possible. By following the label and wearing appropriate PPE, it is possible to occasionally use most herbicides without running the risk of health impacts, but as with everything in life, moderation is key.
Next, after choosing the appropriate chemical, mixing properly, and protecting yourself, you must decide the appropriate time to apply herbicides. Any pesticides that are applied with a sprayer should NEVER be sprayed when it is windy or breezy. This is because sprayers usually apply a fine mist that can easily blow in the wind and kill off-target plants. There is nothing like applying an herbicide to kill weeds in your sidewalk and finding out a week or two later that all of your annuals are dying because of off-target drift. It is also important to apply when temperatures are cooler and air is moving (but not windy). This helps the products dry on the leaf surface and increase uptake while limiting the chances of off-target damage through volatilization.
Volatilization is the process of a liquid applied chemical becoming a gas that can float up and damage plants in the surrounding area. This commonly occurs on warm humid days when the air is still, which allows the chemical to change phases before the water evaporates and the chemical is taken into the plant. It is quite common in spring to see large deciduous trees that have distorted and damaged leaves on the lower canopy from lawn herbicides that have volatilized and stunted newly emerging leaves. This damage is usually permanently damaging to the leaves being affected but does not pose a long-term concern for the overall health of the plant. In some cases though, heavily damaged plants, especially small trees and shrubs, can be weakened or even killed.
With proper application and safety precautions taken, it is possible to apply most herbicides without much risk but of course there is always an exception to a rule. That exception is where I find myself time and again on my soapbox denouncing a specific type of herbicide. I personally and professionally would never use or recommend use of any herbicides that are labeled as controlling weeds for an extended period of time. Most of the major companies have put out products in the past decade that offer multiple months of weed control, up to even one year. These products are usually a mix of multiple chemicals that kill existing vegetation and then sit in the soil, waiting to be taken up by roots of newly growing plants to kill them far after the initial application. Most of these products have glyphosate which will only kill if applied directly to green leaf tissue or paint on cut open wood. The second chemical is usually imazapyr or imazapic which is soil-active and has a long half life, meaning that it will stick around and keep on damaging long after application.
Most ‘extended control’ herbicides are labeled for places like patios, driveways, and other hardscapes and that is where they are most useful. It feels good to only have to apply herbicide once a year to your paver patio and know that you won’t have weeds in the cracks, plus you are using fewer chemicals on your property. What most don’t consider though are the roots of nearby trees and shrubs that have grown around and under these areas. These plants can easily uptake the soil-active herbicide from long distances and kill the plants even if they are a dozen yards away. Sadly, when this damage occurs, there is likely nothing that can be done to fix the damage as the herbicides are now locked inside of the plants and will continue to damage until the product breaks down.
In one extreme example, a property owner consulted to determine why all of their trees around their property looked sick. When driving onto the property, it was almost immediately evident what had occurred. All of the trees adjacent to the pea gravel driveway and paver driveway apron had either died outright or had extremely small/contorted foliage, a hallmark of herbicide damage. After consulting with the property owner, it was discovered that a readily accessible ‘extended control’ herbicide had been sprayed on the driveway just as the label indicated. While everything was done properly, the trees still died because the trees’ roots had spread under the driveway and absorbed the soil-active portion of the herbicide. At the point of inspection, it was determined that nothing could be done to remediate the damage and that the trees would likely die. If a product can continue killing for a full growing season, then it is obviously a very stable and resilient chemical that is likely to come with significant risks.
As with everything in life, moderation is key, and that goes for the application of any herbicide. They can be an effective tool to limit weeding and limit horticultural and/or agricultural losses, but if it sounds too good to be true, then it probably is. Herbicides should also be a small part of an IPM program that emphasizes physical control (weeding) and selection of plants that are strong enough to out compete other unwanted plants. In a busy society, it is far too common to rely solely on chemical solutions to issues be it in your lawn or even your own body health. Judicious and thoughtful applications of herbicides can be very safe and effective but should never be the only means of controlling weeds in a landscape. Be safe and always remember to follow the instructions on the label!
With the ice and snow damage fresh on our collective minds and the forecast showing the possibility of more freezing precipitation, it seems only fitting to discuss winter damage and how to protect trees and shrubs. Not only does snow and ice cause damage to trees, but so can cold temperatures and windburn which are not always identified properly. While it’s possible to protect some plants when it comes to large trees, damage can be inevitable, so it’s important to inspect trees following an ice event to make sure that damage has not caused structural issues that are soon hidden by spring foliage.
When ice or heavy snow is in the forecast, it’s good to prepare your small trees and shrubs by protecting them with supplementary support to keep them from bending and twisting in the snow. One of the most commonly damaged groups of plants is evergreen shrubs with multiple interior stems, such as Arborvitaes, Sky Pencil Hollies, and English Boxwoods. By temporarily wrapping the exterior of the plants with twine or even burlap, it’s possible to prevent any damage before the weather event begins. These wraps should always be taken off before spring growth so that it does not limit shoot or leaf expansion.
In some instances, with fragile plants, it makes sense to set up a wooden A-frame structure over plants that has horizontal cross boards that deflect any snow or ice from building up to damaging levels. These protective structures can be put up in the early winter and left up until spring, at which point they can be stored until the next winter.
It’s not always practical to preventatively protect your plants, at which point, it’s important to keep an eye on accumulations during the event so that snow and ice can be brushed or shaken off of the plants. When heavy wet snow builds up on shrubs, it has a tendency to spread out and bend the individual stems away from one another causing damage to the overall form of the plant and often bark damage as well. To prevent this, the plants should be gently shaken or brushed with a broom to knock excess snow loose. This often has to be done multiple times during a storm as it is much easier and less stressful on the plant to gently knock a small amount off rather than further stressing an already stressed branch or stem.
When heavy snow or ice is already built up on shrubs, any extra jostling can cause the stems to snap. With existing heavy buildup, it is often better to leave the snow and ice until the storm has stopped so that the limbs can flex a bit for later removal. Once snow is removed, it’s best to tie up and support any bent limbs as soon as possible to prevent more damage to the bark and underlying tissue when the stem is bent back into place. Leaving limbs and stems bent for extended periods of time will also increase the likelihood of stem damage or death as cracked open bark can allow desiccation before spring growth can close wounds.
Physical damage is not the only threat to plants during winter though it is quite often the most evident and thus easily identified. Cold damage occurs frequently in Central Virginia in the months of January, February, and March when temperatures drop into the teens and single digits. Most plants in the Richmond area can tolerate one to two very cold days without a problem, but extended periods of cold, dry weather can cause significant damage to many evergreens in the area. While cold temperatures can kill some above-ground growth on marginally hardy plants, it is actually the cold temperatures mixed with low humidity that does the most damage, called “winter burn.”
Water will frequently melt in the leaves and needles of evergreen plants from sun exposure even if air temperatures are below freezing. This liquid water can be quickly lost through the leaf cuticle when the humidity is very low causing desiccation and “burning” of the leaves and needles. This damage can be slow to develop and may even show up in the spring when the damaged leaves begin to brown and drop. While it’s impossible to alter the outside temperature, it is possible to limit water loss by wrapping and covering plants with burlap or similar textiles as it limits sunlight on the foliage and also reduces the drying effects of any wind. This protection does nothing to limit freeze damage on marginally hardy plants, but it can be very effective in limiting damage to evergreens.
The final important part of protecting your trees and shrubs is through a thorough inspection following any large snow or ice storm. Especially in ice storms, it’s likely that limbs will split or break without coming out of the tree canopy. This creates weak spots in the canopy, widow makers, and places for decay and infection to enter the plant. Finding damage early is much easier without new foliage on the plants and can prevent new leaves from weighing down an already compromised limb, causing a hazardous failure. Timely removal of damaged branches before spring will allow the tree to begin closing over the wound as soon as growth resumes for the season.
A little bit of time spent before an upcoming storm or even a bit of playing in the snow can help to protect your trees and shrubs from snow and ice damage, but no matter how hard you work, extreme cold is a problem that does not have a solution. If we are unlucky enough to have another visit from the dreaded Polar Vortex again this winter, wrapping plants can buy you several degrees of protection but usually not enough to prevent all damage. Good spring cleanup to remove dead tissue will improve the appearance of the plants and provide room for new healthy growth
It’s an almost universally known fact that trees and actually all green plants are the main source of oxygen on earth. Without green plants, giant or microscopic, life on earth as we know it could not exist. At a young age, we learn that plants take in carbon dioxide and give off the oxygen we breathe. As we age, we learn that plants take in carbon dioxide, water, and nutrients and then utilize chlorophyll and sunlight to break the oxygen free from carbon dioxide and combine it with water (H2O) to create simple and complex carbohydrates.
Plants, and especially trees, essentially create something from nothing. In a natural environment, plants are able to take free resources and create the sugars and cellulose that feed us, clothe us, and shelter us. This is how most of the world sees trees, but there is a hidden side that many people do not understand or really care about, and that is roots. Roots are hidden under the soil, often misunderstood, and most of the time completely overlooked by tree owners. It’s the old adage of “out of sight, out of mind.” Most know that roots provide water and nutrients to trees and act as an anchor, but very few know how roots actually grow and that can lead to many problems.
One of the most surprising things to learn about roots is that they go through aerobic respiration just like animals and need to take in oxygen and give off carbon dioxide to live and grow. Sugars made in the leaves are moved through the tree in a downward flow towards the roots where oxygen and sugars are used to create energy for cell growth. While roots are taking in oxygen, the above-ground portion of the tree is creating much more oxygen than it uses so, as we learned as children, trees and all plants are overall oxygen producers. This surprising fact is made possible by a tiny and very boring-sounding term called “soil porosity.”
If you could take a cross-section of healthy, natural soil, and look at it, it should look like microscopic Swiss cheese or a sponge. The bits of soil, organic matter, and the like should be spaced out by some large and small holes that allow the flow of gas and liquids between pores and into plant roots. These pores allow water infiltration from precipitation and gas transfer and if they are not present, things start to go bad. First and foremost, water infiltration stops so ponding, puddling, and runoff occur, which is an immediate notice to plants and the people living among them. This lack of water flow into the soil can be a nuisance or danger to humans after significant soil disruption, but it is deadly to plants as they no longer have the water that is essential to their growth. This is an acute problem that can quickly bring about the death of a plant, while there is a secondary problem that can take much longer to kill a tree.
While water is the most essential occupier of soil pores, it can still find its way into even heavily damaged soils thanks to its mass that helps it get pulled into the soil via gravity and the surface tension of water that makes it able to flow through even small pores in the soil. The second most essential element for plants’ roots is the exchange and flow of gas in and out of the soil pores. This is where things can go bad without much notice as we don’t see the gas around us and there will never be a build-up of too much gas on the soil as we do with poor water infiltration.
For this reason, soils can be heavily damaged without much attention being paid as tree roots begin to suffocate and die without any sign. This causes a slow and languishing death for the tree as the roots continue to die back closer and closer to the tree. This can easily be seen above ground several years after the damage first occurs in the dieback of branch tips on the exterior of a tree’s canopy. This above-ground symptom usually shows up in a window of 3 to 5 years after initial soil disturbance. In many cases, the root dieback underground has been progressing for so long that the tree is in a steep decline and will be very difficult to reverse without aggressive remediation. With the knowledge of how tree roots work and the essential role soil porosity plays, it’s now easier to understand the main causes of soil damage and how it can be reversed.
The single largest cause of damage to soils is construction, as soil is compressed and compacted either for a solid base for a foundation or simply the traffic of equipment and feet along a pathway. This compaction is essential to our modern infrastructure. Soils must be compacted to provide a stable base and foundation for our homes, roads, and businesses, so not all compaction is bad. It’s when soil is compacted in the root zone of a tree that problems arise. This compaction greatly reduces the soil porosity and can be most damaging when the soil is wet. Roots in areas of compaction are often damaged by construction, but it’s more likely that the soil porosity is greatly reduced and root suffocation begins. As is the case with most things in life, prevention is key.
When working around trees, it’s extremely important to recognize where roots run so that they can be avoided as much as possible while still successfully performing the work. Roots are typically seen as a mirror image of the above ground portion of the tree and this is another significant misconception. Most roots are found within the top 2 feet of soil and can extend well past the drip line of the tree. Roots in most cases stay shallow as that is where the best soil fertility occurs and is where gas infiltration and exchange happens in healthy soils. Many of the small fine feeder roots extend past the drip line of the tree so keeping construction activity far away from the tree is best. If that is not feasible, the general rule is to create a protection zone with a one-foot radius for every 1 inch of DBH (diameter at breast height). Any protection around trees should be a physical barrier with no openings to prevent incursions into the protected zones. Orange construction fence is often enough on small projects but larger chain link fence panels should be used on larger projects. This all occurs when there is proper forethought and planning in regards to the trees, but that rarely happens.
When soil has been damaged due to some form of significant compaction, all is not lost as this can be remediated with proper care and attention. The most important factor is to recognize damaged soil and/or a tree with root damage as the clock begins ticking the first day the soil is damaged. Addressing a compacted root zone or damaged roots directly after the damage has occurred can prevent any significant symptoms of decline and will most likely prevent the death of the tree. After recognizing this damage, the soil must be decompacted utilizing mechanical or pneumatic tools to break up the soil particles and reestablish proper soil porosity. In areas with limited vegetation, a rototiller can be used to break up soil in preparation for planting as newly planted trees and shrubs will not grow well in heavily compacted soils as their roots cannot penetrate the soil at the edge of the dug hole. In newly constructed communities, newly planted landscapes often fail due to high soil compaction that is never addressed. Quite often though, existing plants and their roots must be kept in mind because rototillers will do more harm than good to existing plants.
A simple-looking but highly engineered device called the Air-Spade can be used to blow high volumes of air into the soil to break it up and recreate soil pores all while doing very little damage to existing woody roots. This device used large volumes of compressed air forced through a specially engineered tip that allows the air to break apart soil particles while only hurting fine root hairs that a plant can easily regrow. Large portions of compacted root zones should be tilled using this tool and then composted organic matter must be added to act as a long-term protector of porosity. After the soil is tilled and compost is applied, it is easy for the soil to settle and porosity to reduce soon after the treatment. The organic matter in the compost will slowly break down, feeding the tree a steady supply of Nitrogen and leaving large pore spaces long after the initial soil settling. This process can be a bit dirty and is the more expensive remediation option but it works very well to address damaged soils around existing landscapes and trees.
When we look at trees, we see the good they provide us: shade, wood, food, and simple beauty. But we are only seeing half of the tree. The underground portions of a tree are some of the more interesting parts when you think of the job they do. Without healthy soils, it’s impossible to have healthy roots, and without healthy roots, there cannot be a healthy tree. Keeping roots healthy is easy by limiting soil compaction and keeping a natural nutrient cycle around the tree. Fixing damaged soils can be much harder but it is possible in most cases and can be a fraction of the cost of having to remove the tree. Keep an eye on your trees and watch to see if they are showing you symptoms of decline. Dieback at the top and tips of the canopy is quite often a sure sign of root damage and death.
When it comes to birds and trees, most people see the relationship like peanut butter and jelly or spaghetti and meatballs. They just go together. It’s impossible to think of one without the other, and in nearly all cases, it is a mutually beneficial relationship. Trees provide shelter and food for birds, and birds spread the seeds of many trees as well as control pests that may feed on the trees. As with most things in life, there is always an exception to the rule and when it comes to birds and trees helping one another the yellow-bellied sapsucker (YBS) is that exception. The YBS is a native woodpecker species that damages trees in its search for food and in some cases can even lead to the death or dieback of trees that are the target of this bird.
I first came across the damage of YBSs early in my career when I was called out to diagnose the dieback on a Nellie Stevens holly that was declining and had a dead top. It was easy to see that the stems of the plant had been injured with much of the bark being removed in odd, almost honeycomb-like, sections that had girdled the stem and caused the area above the damage to die. Immediately the thought of European hornet damage arose as these insects are known for stripping back and even some softwoods to create the paper material for their nest building. I was convinced that a bark treatment would prevent future damage and with a treatment applied, I moved on with little expectation of future issues. Optimism was met with disappointment when damage continued and only then did I realize I was facing an uphill battle.
Yellow-bellied sapsuckers are a unique woodpecker species that gets food in many ways including foraging for fruit and insects, drinking sap, and even baiting insects with sap. Most woodpeckers are known for their rhythmic pecking on large dead limbs to excavate insects from decaying portions of trees. The YBS is not a species that likes to wait around for things to happen. They take action to get food coming their way. Just like their name implies, these birds do indeed suck the sap out of trees by pecking away the bark to create a sap flow from which they drink. They are also quite ingenious as they use this sweet flowing sap to attract insects and then eat the insects as they gather. While the reduction of insects around the tree is usually a good thing, in this case, the damage is worse than the benefit.
Damage from YBS can be seen on many different tree and shrub species, but the most heavily affected plants are hollies, maples, pecans, hickories, and a variety of small, thin-barked species that are commonly used in landscapes. The damage usually appears as a series of small circular holes that are present in a horizontal line around the trunk or stem of trees. This damage is commonly mistaken by homeowners as a sign of wood-boring insects, and misapplication of chemicals can easily occur. With smaller trees and on smaller diameter limbs, damage can appear as large patches of bark that have been removed, exposing the wood underneath. It is also highly likely that once a tree has been targeted by YBS that it will be used as a feeding site in the following years, further compounding the damage as more bark is stripped away annually. It’s in these cases that treatment or prevention becomes important to stop stem and branch girdling.
YBS are migratory birds and are protected by law, so there are thankfully no methods for poisoning or destroying the birds, but that does reduce the number of ways to protect trees from their damage. The most effective DIY treatment is to prevent the YBS from accessing the bark. This can be done by netting smaller trees and shrubs to eliminate access altogether or through wrapping of previously damaged stems and limbs with burlap. Luckily, the new fad for parties and weddings is the rustic aesthetic which has introduced a significant number of burlap fabric options, including rolls of burlap ribbon that can easily be wrapped around trees. The only issue with this approach is the cost of materials and the limitation of only being able to protect the tree in areas that are easily accessible.
Another bit of luck is that it can be easy to predict when this protection needs to be installed. The YBS is a migratory bird that uses the Mid-Atlantic region as a stopover during the migration from their summer breeding grounds in the far Northeast to their overwintering locations in the South and Mexico. This places the birds in our region in the early October to November range on their flight south and in January to March as they make their flights back north. Over the years of watching the damage, I have come to see much more damage in our region during the return flight north in the very early spring. I assume that this is caused by a great supply of other food during the flight south in autumn and the relative dearth of food during their northern flight, requiring sap feeding and insect baiting. For this reason, I always suggest homeowners install protection on vulnerable trees before Thanksgiving and then remove any barrier materials before growth begins again in the spring to prevent damage to newly expanding leaves and growing stems.
While the yellow-bellied sapsucker can be a nuisance, it is never enough of a problem to call for drastic measures such as poisoning or killing the birds and should be addressed as such. A little bit of prevention can go a long way on small trees and as trees grow large enough, the birds cannot do enough damage each year to cause much if any dieback or decline. Keep an eye out for these little birds in the late winter and early spring and if you see trees weeping and bleeding during that time, take a closer look. It is likely you will find small holes drilled in the tree and you will know that there is a yellow-bellied sapsucker nearby, filling its belly as it makes its trip back north.
It’s almost time for that favorite fall pastime: leaf-peeping. Soon there will be countless photos of glowing, multicolored trees posted all over social media. But most people don’t really know why trees do this or what color change can indicate if it shows up a little too early. This won’t be a class on biology but will hopefully give you a new insight into what those colors mean and if it is actually a sign of hidden tree issues. With a little knowledge and a little bit of looking up, it may even be possible to determine dying branches, declining trees, or maybe just a tree that’s a bit thirsty.
Most of us learned in school that trees change color in the fall as a way to conserve resources, as pigments such as Chlorophyll, Carotenoid, and Anthocyanins are broken down into simpler chemicals and pulled back into the tree before leaves fall to the ground. These chemicals are recycled in the coming year as the tree puts leaves on in the spring. Changing temperatures and reduced light levels trigger the trees to begin the process of reabsorbing the nutrients. The first pigment to be broken down in the leaf is the green Chlorophyll, leaving behind the less prevalent orange-colored Carotenoid and the reddish to almost blue Anthocyanins. The concentration of these pigments in the leaves of different trees will dictate what color you see.
As fall approaches many people love to discuss whether or not it will be a year with good fall color which can be heavily dictated by the weather in the months preceding. A dry and stressful year for the trees, for instance, usually creates a lackluster fall display. This is because the trees either move through their color change much more quickly or simply drop their leaves without much of a color change. This is a survival adaptation to simply go dormant before the tree has to suffer more stress. A lack of good fall color can also be caused by the inverse: too much rain in the late fall, which floods the leaf tissue with water and essentially dilutes the colors. These stress-induced changes can help us diagnose issues in individual trees.
I have a city sugar maple planted in front of my house, and as with many open-grown maples, it has grown with very poor architecture, with a limb shooting out and trying to become the main leader of the tree. This has left a stunted and somewhat lackluster central stem. Not only is this stem stunted, but it is always the first portion of the tree to change color in the fall while the rest of the tree maintains a deep green background. While this could be seen as a desirable outcome with extended fall color arising from the issue, it actually acts as a signal that something is wrong in the tree. Quite often trees will have one or two low branches or sections that prematurely develop color. It’s likely that those limbs or areas will be unhealthy or even dead in the following growing season. The tree senses a lack of vigor in those areas and takes action to get every last bit of energy and nutrients out of it before evening considering shutting down the rest of the tree.
A similar situation occurs with newly planted trees, which can easily be seen in planted rows of the same species such as those in commercial or community plantings. This time of year the stressed or poorly planted trees will begin to show color much sooner than other adjacent trees as they are hurrying to go dormant before they have to endure further stress. When this occurs, it is almost always a root issue and by identifying these trees, it’s possible to give them the additional support and care they need in the following growing season. A little work on the root zone to improve soil conditions can quickly turn around a tree that is struggling as long as it is caught before the tree irreversibly declines.
Some trees also use early color and leaf drop as a survival strategy to get through the rest of the growing season with color and leaf fall sporadically occurring as early as July or August. This occurs frequently in river birches and tulip poplars as they are both fast-growing and water-loving trees. In the spring these species put on large amounts of growth when water is plentiful and as the rain reduces in the summer, the trees need to cut back on their water loss from foliage. Leaves scattered throughout the canopy begin to turn yellow and fall, causing a concerning site for the tree owner. This reduces the overall leaf surface area on the tree and thus reduces the loss of water from the tree, allowing it to maintain proper moisture levels even when rain is scarce.
One dissimilar situation is the tree species that simply drop their leaves earlier than most others. Black Walnuts are a peculiar tree as they are nearly always the first tree to drop their leaves and the last to put new ones on in the following year. This has nothing to do with stress. It’s simply the natural characteristic of the species. Ash trees also drop earlier than many other species but can put on quite the show when they do, creating an almost glowing canopy of many different colors.
While not all trees provide showy fall colors, we’re lucky in the region to have many that do. But don’t dismiss the colors as just an aesthetic benefit. Pay attention as the show may actually be the tree signaling an issue that needs attention. Here’s to what will hopefully be a fall filled with lots of happy and dazzling trees!
With a taste of cooler temperatures last week and fall-like weather right around the corner, I find myself planning more adventures, get-togethers, and festivals now that I won’t melt under the summer sun. These adventures find me moving all about the greater Richmond area, from Ashland to Petersburg, and when I find myself to the southern end of our region, I always do my best to carve out a spot of time to visit my favorite tree.
The Cucumber Tree Magnolia (Magnolia accuminata) in Colonial Heights (click here for Google Maps location) is one of the more visually striking and almost otherworldly trees in the area and deserves a visit if you make your way to the Colonial Height and Petersburg area.
The tree sits in front of the Violet Bank Museum in Colonial Heights overlooking the Appomattox River and Old Town Petersburg. When viewing the tree for the first time, it looks almost comical in size and stature next to the relatively small museum building with its white peeling paint. This backdrop is somewhat fitting though as the tree is aging and is beginning to show its threadbare spots. With estimations of it being at least 200 if not 300 hundred years old, this gradual deterioration is to be expected and is actually quite limited. This particular Cucumber Tree Magnolia is also estimated to be the second largest of its species in the world, with a nearly 23-foot circumference, making it that much more spectacular.
The idea of a record-holding tree usually conjures images of extremely tall trees with enormous towering crowns, but that is not this tree. Instead it’s almost the inverse with a relatively stout height but an extreme girth and outstretched, over-extended limbs that are trees in their own right. The first main scaffold limbs on the tree are at least 24 inches in diameter. They gracefully extend until their massive weight pulls them to rest on the ground. Large pockets of decay can be seen in several of these limbs, so without the support on the ground, these limbs would have likely torn from the tree decades ago. The tree took action to support its failing limbs on its own while many failed attempts by human intervention can be seen on the tree.
Viewed up close, a variety of failed arboricultural practices can be seen almost as a museum in itself. Large pilings have been placed in the ground to hold up several of the low limbs, which can be argued do as much if not more damage than the tree supporting itself on the ground. Scattered throughout the canopy are decades worth of steel cables and supports that long-ago arborists installed to maintain the tree and with time many of them have broken or gone slack. It’s most interesting to see such failed support systems hanging from limbs that have once again provided their own support on the soil. One very odd addition to the tree is an old technique used to cover holes and cavities in trees: the much dreaded concrete. A large over-extend limb obviously had a decay spot in the past and well intentioned caretakers took on the project of filling the void and sculpting a brick pattern into the concrete wedge place in the limb. As arborists now know, concrete is never a good choice for filling wounds and this tree is the poster child as the branch is now almost completely decayed leaving behind a brick textured chunk of concrete clumsily sitting inside a once-enormous branch.
When I began my career in Richmond caring for trees, I was appointed the task of monitoring and caring for this amazing tree. As I learned more about it, I felt a real weight on my shoulders to care for it. This weight eventually turned towards reverence as it became clear that my input was likely inconsequential. It has lived for easily over a century before I was born and, barring a catastrophe, will likely outlive me. This tree has seen more history than we can imagine and is even rumored to be a campsite of high-ranking leadership during the Civil War’s Battle of the Crater. If you find yourself south of Richmond this fall, I highly recommend stopping in to see this remarkable tree before nature or man cause its decline. Take a moment to appreciate what this tree has seen and all of the adversities it must have overcome to grow so large and survive for so long.
It was several weeks ago that I received a phone call from a colleague in the tree care industry asking me if I had seen a lot of bark coming off of sycamore trees around Richmond, and it sparked the realization that, yes, indeed, I had.
While this is not an unusual thing to see when large amounts of bark begin to fall, alarm and concern are the first reaction from homeowners as many believe falling items must indicate a problem with the health or safety of the tree. In many cases, when bark splits, exfoliates, or simply falls off, it can be a sign of a very healthy and happy tree. The important thing is to be able to identify when it is a good sign and when it can be a sign of bad things to come.
It was only a few years ago that Richmond had several very wet summers, and many area trees showed their appreciation by growing in a way that we had not seen in quite some time. Not only did their annual growth rings show an increase in growth and wood production, but the thin-barked trees created lasting signs with splits and fissures in the bark along the stems and branches. This can be equated to stretch marks as the trees grew too quickly for their skin and had no other option than to split and create wound tissue to allow for the unexpected growth. Remember, that trees will grow as much as they can in a growing season only limited by their resources which is almost always water in Central Virginia. When bark splits, it can be a very distressing sight but as long as only the bark is splitting without any wood damage or bleeding from the area, it is likely not an issue.
Similarly, many thin bark trees such as sycamores, crape myrtles, and lacebark elms shed sections of their old bark as the tree grows and new bark develops. This usually occurs in mid-summer at the peak of growth creating a bit of a mess around the base of the tree. Luckily the bark is always quite thin — almost papery. Many of these trees are actually planted for this characteristic. The new bark is usually colored differently, so the stems develop a pleasing aesthetic. When this occurs, do resist the urge to help the tree out by pulling the old bark off prematurely. This can expose newly developing bark that is not yet ready to be exposed. Trees with exfoliating bark are a wonderful addition to the home landscape as they often add welcome visual interest during the dormant season.
There are also a lot of trees that begin to shed blocky, thick bark as they develop into maturity leaving behind small and somewhat uncharacteristic bark. This is very common in tulip poplars, flowering dogwoods, and even white oaks to some extent. This is also quite concerning to tree owners as the tree has grown for one way over a very long time and then begins to change in a location, usually around the base of the tree, that does not seem logical. Due to the size and maturity of these trees, it is likely a good option to have an arborist take a look, due to the risk the tree could pose if the bark change is a sign of something a bit more sinister.
When trees lose their bark in what seems to be an extreme amount, when it is occurring in the upper canopy of the tree, or when you can see decay or exposed wood behind the bark, it is usually a sign of damage or decay. These are the situations that would require the need for an arborist to examine and diagnose what may be causing the problem. Several diseases will cause the death of the cambium directly under the bark of the tree which allows the bark to detach from the tree and come off in chunks. These diseases can kill the tree if left unattended and loose-but-still-attached bark can become a breeding ground for pests. If there is a question about bark loss, it can be a simple as taking a picture of the area, identifying the species of tree, and sharing it with an arborist to determine if it is a cause for concern.
If you have lived in Central Virginia for any period of time, you know that the weather can keep you on your toes. And if you don’t like the conditions, wait an hour, and things will probably change. This can make gardening and keeping your plants and trees healthy a real challenge. Sometimes you may feel like you need an advanced degree in horticulture to succeed in keeping a garden.
Over the past few years, we have seen some of the driest years followed immediately by some of the wettest years on record and this has left our plants and urban forest stressed and looking for a reprieve. We as diligent gardeners take it upon ourselves to help balance out the water needs of our plants, but sometimes we do more harm than good.
Often I see a homeowner, with all the best intentions, watering their plants when the soil is already heavily saturated and the plant is beginning to drown. This happens frequently because plants only have one way of showing issues with soil moisture and that is through wilting which is a universal sign to many of drought stress. Overwatering can frequently cause root rot diseases which decay fine root hairs that actually do the heavy lifting of water uptake.
When these root hairs are damaged by root rot organisms, the plant can be surrounded by water but very little is available so the plant shows signs of drought and our first inclination is to add more water to the soil. This then furthers the disease cycle, allowing the root rot to flourish, limiting water uptake by roots, and the feeling that more water is needed, creating a feedback loop that only ends when the plant dies. Another place this can be seen is in areas with poor drainage or locations where we channel and direct runoff, such as culverts and downspout outlets.
The best way to avoid overwatering is to get down and dirty with your plants. If you’re watering and haven’t checked the soil to see what the moisture level is like, it’s similar to a doctor prescribing medication without even seeing you. This can create deadly problems. When plants are wilting and show water stress and your soil is already wet or even saturated, watering needs to be slowed down but not completely stopped. This is akin to the plants going cold turkey which, will almost immediately kill them as they can no longer mine for water due to root loss. A slow drawback on watering is the solution. It allows the plants to slowly acclimate and regrow roots as the root rot diseases reduce.
The best “rule of thumb” for watering is deep and infrequent (or my favorite: the “rule of pinky”). If irrigation is used, infrequent but deep soakings keeps plants hardier as they still get the water they need but have to work for the water in between watering. If watering is needed on individual plants and a hose is used at the base of the plant, a flow of water the diameter of your pinky for an hour or so is great to keep the soil moist deep into the root zone. This should be performed once a week during normal conditions and at least twice weekly during drought conditions. The use of a GatorBag can also eliminate the need to constantly check and remember to water the tree.
Be mindful that water can be a double-edged sword. It is essential for the health and growth of your plants, but too much of a good thing can be just as bad or even worse than not enough. Be water-wise when providing for your landscape and take a minute or two before turning on the water to make sure that your plants actually need it.
Spring brings out all of the bugs, and while most of the ones we think about are damaging or annoying, there are thousands that go about their life nearly out of sight and out of mind. Every once in a while, one of these thousands can be pretty enough, large enough, or odd enough to catch our attention as we rush through our own lives. The jumping oak gall wasp is just such an insect. You can see it on many of Virginia’s oaks this time of year, and it might just warrant a pause in your day to see something unique and new.
The jumping oak gall wasp will almost exclusively damage mature white oaks (and other oaks in that family) around home landscapes. In most cases, tree owners never notice the insects or the galls they create on the white oak leaves, as they are tiny and non-damaging until the population hits a level that the tree cannot sustain. When this occurs, the young leaves will brown and prematurely fall causing stress to the tree. The real reason that jumping oak gall wasp is of interest is because of the jumping action that gives it the title.
The galls are actually tiny vegetative growths made by the tree’s leaves. They act as shelter and a food source for the larvae of a small stingless wasp where the insect spends most of its life. The gall wasps fall from the trees in late spring and will do a little dance on the ground to lodge themselves into cracks and crevices to wait out the rest of the year before they emerge as adults the following spring, when they start the lifecycle again. (Click here to see the jumping gall wasp in action.) If you have a white oak in your landscape, you can likely see this occurring on your sidewalks and driveways right now. This movement is caused by the larvae moving inside the dry gall much the same way “Mexican Jumping Beans” work.
As white oaks begin to leaf out in the spring, the adults hatch from the overwintered galls and begin the cycle again by laying eggs on newly emerging leaves when they are extremely small and still expanding. The eggs produce hormones that hijack the normal leaf growth and make the leaves grow fleshy tissue around the developing eggs. As the eggs hatch, the larvae begin to feed on the gall and grow. In heavy infestations, extensive foliage damage occurs and the oaks will drop the damaged leaves in an attempt to protect themselves from further injury, while light to moderate infestations go unnoticed. In some cases, it can warrant supplemental watering, mulching, and soil amendments to help reduce the stress caused by the leaf drop but preventative treatment is not recommended as it is very hard to time properly and requires very large applications of broad-spectrum insecticides that can damage non-target insects and invertebrates.
If you have white oaks on your property, it is likely that you have seen what looks like very tiny orange to tan dots all over your car, driveway, sidewalk, and landscape plants. These dots are about the size of the head of a pin and are extremely easy to overlook, but will hopefully now your eye will know what to look for. Take a minute or two to walk your landscape and see if you can detect the telltale jumping of this little wasp as it goes through its life underfoot and nearly out of sight.
It’s that time of year when you might find yourself admiring the trees along the highway covered in cascades of purple flowers. If you’re left wondering what type of tree that may be and why you never noticed it before, it might surprise you that it could be anything from an oak to a pine covered in those beautiful flowers. What you are seeing is not the tree but, actually, the plant that is slowly killing it. Let me introduce you to my favorite plant to hate — Wisteria.
My distaste for Wisteria does not spread across the genus but only falls on the two Asiatic species, Wisteria sinensis and Wisteria floribunda, which are both non-native, introduced species that have become exceptionally invasive in the urban forests of the Mid-Atlantic. This flowering vine will establish itself quickly in nearly any garden and begins climbing anything it can reach. Once fully established it will begin its spread through both seeds and above-ground stolons. A small trellis of Wisteria beside a deck or patio can quickly turn into a backyard filled with vines and nearby trees being overwhelmed. As the vines grow they climb as high as possible to seek out sun and will climb to the top of 50- to 70-foot tall trees, the whole time growing in diameter and slowly choking the tree. Heavy infestations can choke out entire trees and even woodlots. But what to do if it has already started its invasion of your property?
Control can be a tedious and sometimes hard-fought battle that may need a lot of elbow grease, herbicides, and even professional help. Smaller plants and clumps can be culled by simple hand pulling with a watchful eye for additional sprouts popping up. Larger infestations may require chainsaws, herbicides, and even the ever-popular goat to get things under control. It may take several years of repeated treatments to full eliminate the vines.
One final tidbit to note is that while goats can eat modest amounts of the plant, Wisteria should definitely be kept away from children or curious pets as the smooth and sizable seeds are very poisonous. And the rest of the plant poses a smaller threat, but still a threat if eaten. This does not mean that Wisteria doesn’t have a place in our landscapes and urban forests. It is indeed a beautiful plant that adds a splash of color in the spring. The native version of the plant, Wisteria frutescens, will still give you the showy flowers and some climbing without the nearly uncontrollable spread. It is also very well suited to remaining a small clumping shrub without support for climbing. If you can’t find this species in your local nursery, ask for it by name, which may help them to decide to stop carrying the Asiatic species.