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.