The River in Bloom

September 9, 2020 · 1 minute read
The River in Bloom

First it’s the crickets in early morning. Next it’s the light: the shifting, slanting gentle light of late afternoon. We are turning toward the night-day balance of the autumn equinox. The crickets and the angle of the light seem to signal that it’s a good time to be still and quiet, to pay attention. The wildflowers of waning summer are one of the rewards. In late August and early September there is much to see in bloom along the river — and hopefully in your own yard. Let’s start there.

I was busy listening to the crickets through an open window and avoiding my work when I noticed—really noticed—the seasonal profusion of Tick-trefoil accenting our walkway and paths.

If the common name doesn’t put you off, the seedpods to come will really grab you (mostly by your pantlegs). Tick-trefoil — genus Desmodium — is a perennial legume spread by its seeds. There are 20 Desmodium species native to Virginia, at least nine of which can be found in the Richmond area. I haven’t gotten a positive identification on mine, but my best guess is Desmodium glabellum. I suspect that Desmodium in yards frequently suffers the fate of native
species vulnerable to being labeled as “weeds”, but those delicate orchid-like flowers on wispy stems are a late summer joy and their seeds are a valuable wildlife food source while the foliage provides good cover.

This particular species of Desmodium likes the dry upland woods of our yard. But along the James River nearby, other native species are heralding the end of summer. What can you see while taking a walk along the river? Here are just a handful:

Partridge Pea — Chamaecrista nictitans
Mistflower — Conoclinium coelestinum
Hollow Joe Pye Weed — Eutrochium fistulosum
Oxeye Sunflower — Heliopsis helianthoides
Orange or Spotted Jewelweed — Impatiens capensis
Bear’s Foot or Hairy Leafcup — Smallanthus uvedalia (each bloom with a visitor!)
New York Ironweed — Vernonia noveboracensis





August is for Defeating Stiltgrass

August 11, 2020 · 4 minute read
August is for Defeating Stiltgrass

“Thrives in diverse environments and adapts readily to varied conditions. A prolific producer with multiple strategies to achieve success. Makes the most of opportunities.”

If invasive plants had their own LinkedIn accounts, this might be on the profile Japanese stiltgrass (Microstegium vimenium) and August is the month of its ascendency when it densely crowds roadsides, drainage ditches, utility rights of way, trail edges, stream banks, and just about any place where a little sunlight interrupts the shade, particularly where the ground has been disturbed.

Japanese stiltgrass along a drainage leading to the James River Park System. Photo: Laura Greenleaf

Japanese stiltgrass was my “gateway invasive”—the species that introduced me to invasive plant ecology when I first became a Virginia Master Naturalist ten years ago because it had already dramatically altered the northern Blue Ridge woodlands where I’d grown up. In the invasive plant geek parlor game of “If you were a time-traveling superhero, what invasive plant species would you stop?” I
don’t waffle over my answer. In the mountains and piedmont, August is the season of stiltgrass dread while the fall and winter holidays bring the despair of the inescapable posthumous hummocks carpeting the forest floor. (It was dried-out dead stiltgrass that first invaded North America, used as packing material and loaded with seeds.)

Stiltgrass in winter. Photo: Crooked River Cooperative Weed Management Area

But don’t let me bring you down, read on!

Stiltgrass is an annual grass from Asia that reproduces primarily through seed production. It’s one of the most destructive invasive plants in North America and nearly ubiquitous in eastern deciduous forests where, by late summer, it forms stiltgrass seas that turn to vast masses of dried “thatch” in winter.

No invasive plant species proves that “timing is everything” quite like stiltgrass. Manage it properly in late summer prior to flowering–every year it grows–and you can curb its spread, even eliminate incipient incursions. But misguidedly mow, weed whack, or pull it after it’s gone to seed and you’ve just been an unwitting accomplice in an ecological crime. Do the same too early, in June or July, and stiltgrass will respond with vigorous new growth.

Stiltgrass in The Wetlands. Photo: Laura Greenleaf

How does stiltgrass stand out within the ranks of invasive plants that by definition dominate the environments they invade?

 Each plant can produce as many as 1,000 seeds.
 Those seeds can remain viable in the ground for up to five years, possibly longer (germination rates do drop off dramatically after two or three years).
 Stiltgrass spreads in sun or shade, dry or moist conditions.
 But it particularly loves wetlands and riparian areas (adjacent to streams, creeks, and rivers) and the flowing water carries stiltgrass seeds downstream to new outposts.

Stiltgrass also gets some help from us, animals, and the elements:

 Seeds hitchhike on the bottoms of our hiking boots and the tires of vehicles and machinery.
 White-tailed deer–particularly where populations are too high– heavily browse native plants, giving stiltgrass an advantage, while seeds get a ride on hooves and hides.
 Off-leash (and off-trail) dogs also can transport seeds on their fur.
 Stormwater runoff transports and deposits stiltgrass seeds.
 Land management and landscaping practices in natural areas that disturb soils and cut back native species woody and herbaceous vegetation set the stage for stiltgrass colonization.

Identifying stiltgrass is easy, but there are native grasses that might become cases of mistaken identity. Here are the basics:

 Stiltgrass leaves are 2 to 4 inches long and about half an inch wide,
well-spaced alternately on the stem, with smooth edges
 Leaves sport a distinctive silvery, off-center mid-rib
 At maturity, stiltgrass can reach a height of three feet or more
 Stems often branch in multiples from the base
 Seed heads extend from delicate stalks Alabama Natural Resources provides this excellent Field Guide to Identification of Japanese
Stiltgrass (with comparisons to look-a-like species).

So now that you’ve just realized you have stiltgrass on your property, what should you do about it? Here is the one nice thing I have to say about stiltgrass: it has a weak root system that pulls up easily. If you have just small patches of stiltgrass, hand pulling is the way to go. Hand pulling also allows you to carefully avoid collateral damage to native plant species, including grasses like Virginia white-grass and deer tongue grass. If you have larger expanses of stiltgrass and you’re confident that no native plants are hiding out, you can use a stringed weed trimmer to cut the stiltgrass as close to the ground as possible. I still use the (freshly sharpened) sickles and weed whips my family used to open trails and
other clearings at home in the ‘70s and ‘80s . . . . trails and clearings that were colonized by stiltgrass by the new century!

Whether manual or mechanical, you want to tackle stiltgrass soon, and since it does not uniformly go to seed at the same time in all habitats, inspect it closely to make sure seeds have not yet formed. For more detailed information on managing Japanese stiltgrass, check out this fact sheet from Blue Ridge PRISM.

Laura Greenleaf is a Certified Virginia Master Naturalist and a founding steering committee member of the James River Park System Invasive Plant Task Force. She lives near the Pony Pasture section of the JRPS.

Time for a Change: Replace Bradford Pears with Native Trees

July 14, 2020 · 3 minute read
Time for a Change: Replace Bradford Pears with Native Trees

“Invasive plant species are an underappreciated threat to our native plants and wildlife. Bradford pear is one that was introduced intentionally, but has shown to have undesirable traits horticulturally and ecologically. It should be abandoned in favor of native species.”

–Kevin Heffernan, DCR Natural Heritage Stewardship Biologist Richmond Zen Head Priest

A tree stump isn’t usually something that pleases me. The exception: the stumps of invasive trees — Tree of Heaven (Ailanthus altissima), Royal Paulownia (Paulownia tomentosa), Mimosa (Albizia julibrissin), Norway Maple (Acer platanoides), and yes, Bradford pear (Pyrus calleryana). These species impoverish our natural areas and do little to enhance the health of our built environment when compared to the native tree species they displace.

Beginning in 1909, the Bradford pear was introduced from its native China and Taiwan as an antidote to the fire blight epidemic in pear fruit trees. The Bradford pear (or Callery pear) — with its uniform shape, medium mature height, ample shade, and abundant blossoms — became a common ornamental presence in yards and parks and along streets throughout the Southeast United States. The tree produces sterile fruit, but by the turn of the 21st-century hybridization with cultivars triggered fertile seed dispersal across the Southern landscape.

Since then the Bradford pear has risen to the top of our least-wanted invasive plant lists. The Virginia Department of Conservation and Recreation’s Natural Heritage program ranks it as having medium invasiveness throughout Virginia. The South Carolina Forestry Commission and Clemson University have partnered to pioneer the “Bradford Pear Bounty Program”, motivating citizens to take down their Bradfords in exchange for native tree replacements.

In mid-March, my last trip down interstate 95 to Richmond before the pandemic lockdown displayed just how much Bradford colonization has advanced; highway edges and open areas by interchanges were dense with a monoculture of blooms that are no signifier of a Virginia spring. I took some comfort in knowing that I’d already been part of a small effort to curb the Bradford pear invasion in a Richmond city park.

Aside from their ecological cons, Bradford pears are also short-lived (about twenty years) and prone to breakage. This promenade of pears had already spawned offspring into a natural area of Forest Hill Park.

The previous November members of Richmond Zen, having successfully applied for a Community Roots grant from Richmond Tree Stewards, partnered with Department of Parks and Recreation staff at Forest Hill Park and the Tree Stewards to replace the avenue of Bradford pears that previously stretched down a hill below The Stone House.

The pear replacements had to conform to the public walkway’s formal setting and purpose—a different set of goals and criteria than when planning for habitat restoration—and species selection had to further take into account the availability of saplings rather than bareroot seedlings (the go-to for habitat restoration projects). The additional goals of adding new species to Forest Hill Park’s inventory and striking a symmetrical balance to the walkway arrived at alternating lines of Valley Forge Elm (Dutch Elm Disease-resistant cultivar of Ulmus americana) and Nuttall Oak (Quercus nuttalli). One more pre-planting task remained: notifying park neighbors and visitors of what was to come and understandably registers as a shock and a loss – chainsaws leaving behind tree stumps, followed by their removal.

On the sharply cold morning of November 9th, Richmond Zen’s sangha members, family, and friends gathered with Richmond Tree Steward Jesse Wright and Forest Hill Park staff. Within a matter of hours, dormant new life was in the ground.

Seven months later, after a cool and rainy May, the time came to tend the new trees through a Richmond summer.  With support from Parks and Recreation, Richmond Zen volunteers are watering the trees on a weekly basis.

The former Bradford pear alee in spring 2020.

Do you have a Bradford pear that you would like to replace, but need help with species selection? Look no further than the Native Plants for Virginia’s Capital Region guide.  Consider Serviceberry species, Sourwood, and Sweetbay Magnolia among others.

For a deeper dive into the downsides of Pyrus calleryana check out this recorded webinar from the Virginia Association of Forest Health Professionals –  Pretty But Pungent: the Curious Case of the Callery Pear.

Laura Greenleaf is a Certified Virginia Master Naturalist and a founding steering committee member of the James River Park System Invasive Plant Task Force.

On the Fringes with Chionanthus Virginicus

June 17, 2020 · 3 minute read
On the Fringes with Chionanthus Virginicus

Chionanthus virginicus. I type the Latin genus and species into the Digital Atlas of the Virginia Flora and am surprised by the map the entry returns: a red dot in every single Virginia county indicating that Fringetree occurs statewide, “frequent to common throughout”, from dry upland forests to streams and wetlands.

How then did I manage to grow up and live in Virginia’s Blue Ridge, Shenandoah Valley, and northern Piedmont and not come to know this tree by name until moving within the city limits of Richmond? It can take a lifetime — and sometimes just a single tree — to cultivate attention. I’ve known just one naturally occurring Chionanthus virginicus in the city, and no sooner did I make its acquaintance than it was gone—wiped out by a clearcut for new construction. The ground where that woodland Fringetree would now be blooming is paved with concrete and planted with geometric arrangements of Crape Myrtle and other ornamental, non-native landscaping staples.

Though an understory species so modest in size as to sometimes be classified as a large shrub rather than a small tree, Fringetree is a striking attention-getter. In late spring, its frothy profusion of dangling blooms proves both its common name and the etymology of Chionanthus: snow and flower. The fragrant flowers appear on both male and female trees (most abundantly cloud-like on males), but in order to produce the early fall dark-blue fruit so beneficial to native songbirds, males and females must grow in proximity. 

A blooming fringetree is a real attention-getter.

Like the ash trees — the species in the genus Fraxinus — that we are losing to the Emerald Ash Borer, Chionanthus virginicus is one of just a few members of the family Oleaceae native to North America. And also like the ashes, it is a host plant to the Fawn sphinx moth (Sphinx kalmiae) as well as to the Rustic sphinx moth (Manduca rustica). According to Native Plants for Virginia’s Capital Region, Fringetree hosts eight species of native caterpillars on its foliage before it even gets around to luring pollinators with its flowers and feeding songbirds with its berries. The ubiquitous non-indigenous crape myrtles that have “replaced” that wild Fringetree cannot support a single specialist insect species.

The nursery-sourced Chionanthus virginicus most commonly seen in landscape plantings are typically multi-stemmed shrubs no more than 8 to 10 feet tall.  But the forest dweller I knew was at least twice that height on a single branching trunk. I was so taken by that tree that, before its demise, I purchased my own Fringetree at the annual plant sale at Blandy Farm, the State Arboretum of Virginia. Despite the species’ unfussy reputation, the planting location I chose proved to be less than ideal or perhaps I unintentionally committed a local ecotype mismatch. This year the top half of its growth has died. Prior to this reversal in health, my Chionanthus had tripled in height while its stem remained no thicker than a Sharpie. Slow growers, these Fringetrees. I wonder how many Mays the full-grown wild Chionthanus had bloomed before it caught my eye, how many years of growth ended with one thoughtless swipe of a chainsaw.  

So Chionthanus virginicus asks not only for our attention but for our patience.  I look now for sources of seedlings or saplings that will come closest to what nature bestows in the woods. I contemplate my yard’s more sunlit canopy openings and richer soils. Whatever this fall brings, I intend to be planting Fringetrees.

Laura Greenleaf is a Certified Virginia Master Naturalist and a founding steering committee member of the James River Park System Invasive Plant Task Force.

Looking Back, Looking Forward: Fraxinus spp. and the Emerald Ash Borer

May 27, 2020 · 4 minute read
Looking Back, Looking Forward: Fraxinus spp. and the Emerald Ash Borer

I knew it was coming. But that didn’t make the inevitable any less heartbreaking.  Seven years ago I peeled off a loose hunk of bark from a fallen green ash tree in the northern Blue Ridge where I grew up and saw what I’d previously witnessed only on educational alerts – the serpentine “galleries” of the invasive Emerald Ash Borer (EAB) larvae.

By 2016 everywhere I looked I saw the defoliated crowns and “blonding” trunks of ash trees that were dying by the dozens (“blonding”—the shedding of bark—is the work of opportunistic woodpeckers mining the EAB larvae that are feeding on the tree’s vascular system, choking off water and nutrients). And just like back home in the mountains, a few years later I would discover I hadn’t realized how many ash trees lived in the James River Park System until they, too, started dying.

Deadly Invertebrate Invader

The aptly named Emerald Ash Borer, native to most of Asia from the Russian Far East to Japan, made its first documented appearance in North America in southeast Michigan in the summer of 2002 after most likely stowing away in cargo packing material made from wood. A year later it was detected in Fairfax County, Va. but was eradicated before its reconfirmation there in 2008. Regulatory quarantines on firewood ensued, distinctive purple monitoring traps deployed. But Emerald Ash Borer implacably spread throughout Virginia (with a 2019 Richmond region date-stamp) as well as to 35 U.S. states and the District of Columbia and five Canadian provinces, leaving tens of millions of dead ash trees in its wake. (For more on the biology and spread of EAB, visit the Virginia Department of Forestry’s EAB Story Map.)

Elegy for Fraxinus spp.

There are about 40 species of the genus Fraxinus worldwide, 16 in the United States, and of the four found in Virginia, White Ash (Fraxinus americana) and Green Ash (Fraxinus pennsylvanica) are the most common. Found throughout Virginia, White and Green Ash historically made up 2-3 percent of the forest composition and pulled duty as dependable residential and municipal shade trees.  

“The compoundly pinnate leaf structure of Fraxinus”

In a dense forest environment, ash trees didn’t grab my attention. I underappreciated them. But Fraxinus is a giver—ecologically and culturally. Its wood is ideal for tool handles, furniture, veneers, and most iconically, baseball bats. Its loose clusters of pale green to nearly purple flowers fruit to flat, winged seeds that feed songbirds and mammals. According to entomologist Doug Tallamy, in Bringing Nature Home: How You Can Sustain Wildlife with Native Plants, Ash species in Eastern deciduous forests host 150 species of Lepidoptera (butterflies and moths). The National Park Service in the National Capital Region cites 27 insect species including moths, butterflies, and bees that are restricted to ash as their host plant.

Those specialized host relationships include our own native ash borers, but against the invasive Emerald Ash Borer the trees have no defenses; native trees and invasive insects did not co-evolve to develop adaptive checks and balances.  The flashy invader reproduces prolifically, matures quickly, and spreads rapidly both under its own wing-power and by human actions. Where EAB has been present the longest, the mortality rate of Ash trees is nearly 100 percent. With them goes all that they gave—cooling shade, streambank stabilization, food and shelter for wildlife, and a mutually interdependent web of life whose loss is incalculable. In forests, the sunlit clearings they open in the canopy are ripe for colonization by invasive plant species (replanting hard-hit areas with a range of well-suited locally native tree species is a strategy for staving off invasives and fostering biodiversity).

The compoundly pinnate leaf structure of Fraxinus

The survivors

The U.S. Forest Service has dubbed surviving ash trees “lingering ash” and these apparently resistant individuals (a different kind of one percent!) are the subject of long-term genetic research, a  possible key to a future for Fraxinus

For now, frontline response to this late stage of Emerald Ash Borer’s assault continues to focus on treatment of trees that haven’t yet succumbed. The Virginia Department of Forestry operates a cost-share reimbursement program available to individual property owners and organizations. In 2019 the James River Park System applied for and received cost-share grant funding and treated thirteen trees in the Huguenot Flatwater Woods and Pony Pasture park units. Since then, the park system partnered with the Invasive Plant Task Force (and its fiscal agent, Friends of the James River Park) to successfully apply for a private foundation grant that is now funding treatment of an additional 40 trees. Volunteers are identifying good candidates that haven’t suffered more than 30 percent canopy loss. If you notice a tree with a blue ring painted on its trunk: that’s a survivor receiving treatment on a two-year cycle.

Characteristic “blonding” on a green ash tree.

Never say die

Reckoning that the Emerald Ash Borer was inexorably advancing toward the northern Blue Ridge, the same year I first suspected their presence I planted a half dozen green ash bareroot seedlings from the Virginia Department of Forestry in the woods where I had grown up and where ill-fated mature ash trees still gave the appearance of flourishing. If they survived, I reasoned, by the time they matured the Emerald Ash Borer might just be a bad memory. I wish I had planted more. Now I keep an eye on the canopy in Richmond’s parks, hoping to spot a survivor.

Native Shrubs and Perennials for Your Yard or Garden

May 13, 2020 · 2 minute read
Native Shrubs and Perennials for Your Yard or Garden

In my last article I turned my attention—and hopefully readers’ attention as well!–to the naturally occurring native plants all around us that can continue to thrive if we let them. This week let’s take a peek at just a few of the most adaptable spring and early summer-flowering shrubs and perennials native to the Richmond region to consider adding to your home.

(All photos are taken within the city of Richmond at the author’s home and at the Bayscape native plant garden at Good Shepherd Episcopal School.)

Green and gold

Green and Gold (Chrysogonum virginianum)

Green and Gold is a favorite of mine; it isn’t fussy and it spreads by stolons and runners making it a great ground cover in tough areas. It’s shade tolerant and has a long bloom-time.

Golden-alexanders

Golden-alexanders (Zizia aurea)

Delicate and bright, Golden-alexanders prefer moist soil. Butterfly bonus: This is the host species to the Black Swallowtail.

Golden Ragwort (Packera aurea)

Remarkably adaptable to different conditions, it’s no wonder that Golden Ragwort makes its home in every county in Virginia. Attracting pollinators while repelling most herbivores, Golden Ragwort’s full-skirted foliage and abundant bright blooms make it a great choice.

Eastern Blue-star

Eastern Blue-star (Amsonia tabernaemontana)

Seen here just before blooming, Blue-star is truly at home in Richmond, though it occurs infrequently in its limited range.

Woodland phlox

Woodland Phlox (Phlox divaricata)

Skip the cultivars and make way for this shady woodland sign of spring that’s a favorite of native bees and butterflies. 

Lyre-leaf sage

Lyre-leaf Sage (Salvia lyrata) A wildflower that truly doesn’t care where it grows; from roadsides to woodlands, sun to shade, it tolerates both drought and temporary flooding. Lyre-leaf sage is a somewhat deer-resistant groundcover solution with much to offer pollinators including the larvae of several species.

Arrow-wood

Arrow-wood (Viburnum dentatum)

All viburnums are “wildlife powerhouses,” their flowers feed native bees and other pollinators, while their berries are forage for songbirds.

Virginia sweetspire

Virginia Sweetspire (Itea virginica)

Although it thrives with some full sun, Sweetspire can manage well in a mostly shady spot if it isn’t too dry.  Sweetspire nectar is an insect magnet and its vibrant fall color is long-lasting.

Ninebark

Ninebark (Physocarpus opulifolius)

If deer-browse is a problem, this is your go-to hedge. Ninebark tolerates a range of conditions and grows rapidly in a fountain-like form.  

Rosebay rhododendron

Rosebay Rhododendron (Rhododendron catawbiense roseum)  

What do all those cultivars have over this ‘straight species’? Absolutely nothing.  Full disclosure: Richmond is just outside of the Rosebay’s easternmost native range, but it’s just right in a spot by this writer’s porch.

Old habits die hard– especially when non-native ornamentals dominate the aisles of garden centers and the offerings of most landscaping companies — but a little effort and a fresh outlook are all it takes to cultivate habitat at home with native plants beautiful in form and bloom, all the more so because of the life they give.

If you don’t already have a copy, Native Plants for Virginia’s Capital Region is a must that’s available for order or download on the Plant Virginia Natives website.  While not intended to be an exhaustive encyclopedia of native plants of our region, this well-organized and accessible guide is an excellent planning tool.

All plants in accompanying photos sourced from Garden Gate Landscape and Design, Reedy Creek Environmental, and Hill House Native Plants. You can find a list of native plant nurseries on the Virginia Native Plant Society website

May You Bloom and Grow: Native Plant Species to Notice Now

April 28, 2020 · 3 minute read
May You Bloom and Grow: Native Plant Species to Notice Now

Once in a golden hour

there fell to earth a seed

up there grew a flower

the people said, a weed.”

I memorized this little rhyme as a child because a framed version hung on my bedroom wall. But it means more to me now, as a certified Virginia Master Naturalist delighting in every appearance of a native plant in an area so devastated by overwhelmingly extensive invasive plant infestations. 

Treasures still abound — often hidden in plain sight — in Richmond’s parks, along roadsides, and in unmanicured wooded yards. What generations of homeowners often dismissed as weeds have been largely displaced by turf grass lawns, exotic ornamental landscaping, and, increasingly, complete removal of leaf litter (an ecological term – leaves are not garbage, and we need to stop treating them as such). But some native plant species are particularly adept at hanging on given the slightest chance.

Attention is all it takes (no botanical expertise necessary) to truly see and appreciate the indigenous flora of our Fall Line ecosystem. Here is just a smattering of your fellow Richmond residents you may be encountering this spring: 

The “apple” of the Mayapple. Credit: Catherine Farmer

Mayapple (Podophyllum peltatum L.) Found in every county in Virginia, the whimsical Mayapple is a familiar sign of spring in the Commonwealth and it thrives in our local woodlands, particularly well-shaded damp spots, maturing here well before May. The leaves are deeply palmate and if there are two, a single white flower will follow (visible only if you peek beneath the umbrella-like leaves) and later, the so-called “apple”.

The distinctive Mayapple.

Cut-leaf Toothwort (Cardamine concatenata) This diminutive spring ephemeral is one of four members of the genus Cardamine in Virginia. Cut-leaf Toothwort comes and goes quickly in early spring and depends on deep leaf litter for nourishment.

Cut-leaf toothwort. Credit: Catherine Farmer

Sweet Cicely or Aniseroot (Osmorhiza claytonia or Osmorhiza longistylis) These two species of the genus Osmorhiza are prolific, but don’t mistake them for the invasive and slightly similar (at a glance) Garlic Mustard.

Sweet Cicely or Aniseroot. Credit: Catherine Farmer

Rattlesnake Weed (Hieracium venosum) Identified in nearly every county in Virginia (including those with rattlesnakes) Rattlesnake Weed absolutely will not bite, but may surprise you with its bold leaves and spindly bright yellow flower high above. Look for it on edges that have a bit of sun.

Rattlesnake Weed
Rattlesnake weed in bloom

Jewelweed (impatiens capensis) Jewelweed is in its early stages of emergence in drainages, swampy areas, and streamsides in our area; the showy, pollinator-magnet flowers that give it its common name will appear later in the season. Jewelweed has lots of fans among invasive plant warriors because of its ability to stand up to habitat destroyers like Japanese stiltgrass.

Jewelweed

Poverty Oatgrass (Danthonia spicata) Our region is home to many native grasses, sedges, and rushes that (like all native plants) perform crucial ecosystem services where turfgrass does . . . almost nothing (when it comes to slowing and filtering stormwater runoff, a lawn performs not much better than pavement). Poverty Oatgrass prefers drier conditions, but is otherwise not picky. And Curly Grass (as it’s also called) is the host plant to the caterpillars of the Indian Skipper butterflies.

Poverty Oatgrass

Striped wintergreen (Chimaphila maculata) Don’t be surprised if you spot this tiny evergreen in the vicinity of much taller neighbors, the American holly (Ilex Americana). Both occur in acidic soils. Bloom time is still ahead of us, so keep an eye out for the nodding, creamy white flowers late in spring and summer. Find out the meaning of its Latin name and explore the world of the very small in this blog post on The Natural Web.

Striped Wintergreen.

Pinxterbloom Azalea (Rhododendron periclymenoides) We landscape with cultivars, but can they really hold a candle to Virginia’s native azaleas, of which Pinxterbloom is just one of seven? Certainly not when it comes to sustaining life; those seven species host the caterpillar larvae of at least 50 native butterfly species. The Virginia Native Plant Society blog currently features the Pinxterbloom for good reason. 

Pinxterbloom Azalea is Forest Hill Park. Credit: Stan McCulloch

This is just a handful of the locally native plant species you may be seeing in your neighborhood and in our parks now and year-round. If you’re lucky enough to have them right at home, keep up the good work of nurturing nature!

Home Is Also Where the Invasives Are

April 9, 2020 · 3 minute read
Home Is Also Where the Invasives Are

With Richmond, like the rest of Virginia, under a public health emergency Executive Order to “remain at their place of residence”, we’re all getting better acquainted with the places we call home. Fortunately, staying at home doesn’t mean staying inside. And tackling invasive plants is a great way to nurture nature and yourself:

  • It’s a satisfying stress reliever; your brain gets a rest while your body gets a workout, and you are rewarded with measurable results.
  • Controlling invasive plants is essential for a more ecologically healthy yard; if you want your home to be habitat for more than just you and your family, this is step one.
  • You’ll earn the right to dream and plan . . . about planting locally native plants in the fall.
  • You’ll be helping out our park system even while the Task Force has to suspend public volunteer events. Making progress in the park means slowing the spread from outside of it.

Even the smallest yard likely harbors invasive plants, so read on for identification and management guidance on a few of the JRPS Invasive Plant Task Force’s “least wanted”, all Virginia state-listed invasive species:

These Vines are Not Fine

Truetimber’s own Mike Mather recently explained how to rescue your trees from the dangerous burden of English ivy, but other invasive vines may lurk in your yard:

Perwinkle (Vinca major, minor)
  • Winter Creeper (Euonymous fortunei) hangs out with English ivy and behaves just as badly; the two dominate in the James River Park System, threatening our city’s tree canopy and carpeting once rich woodlands.  Free your trees and pull the ground cover, getting out all the roots as much as possible.
  • Japanese Honeysuckle (Lonicera japonica) is the most widespread invasive vine in the eastern United States, smothering native vegetation and girdling to death tree and shrub saplings.  Locating and pulling the rooting nodes of this invasive is uniquely satisfying.
  • And while you’re at it . . . reconsider that Periwinkle (Vinca major, minor). This still popular landscaping vine is also invasive.

Herbaceous Horrors

As you may have read here, Fig Buttercup (Ficaria verna) is one of the most recent invaders of the park system threatening our indigenous spring ephemerals (wildflowers), but it isn’t spring’s only invasive target.  

Garlic mustard in bloom.
  • Garlic Mustard (Alliaria petiolata), another park invader you may find at home, is easier to remove because it’s a ‘herbaceous forb’, not a vine or woody stemmed plant. Garlic Mustard displaces native spring wildflowers and is toxic to the larvae of our butterfly species whose host plants are natives in the Mustard family.
  • This biennial species takes two years to mature; first-year plants are low “rosettes” with kidney shaped, scalloped leaves that become more heart-shaped in their second year when the plant flowers and seeds. Pull these plants, getting the entire tap root, prior to flowering and setting seed. Bag and dispose of any plants that already have flowered. The ideal window for removing Garlic Mustard in our area has just closed, so use caution. For detailed identification and instructions, see this action alert from Blue Ridge PRISM.

Don’t Hedge Your Bets – Get Rid of These Shrubs

The two most dominant invasive shrubs in the James River Park System are Amur Honeysuckle (Lonicera maackii) and Chinese Privet (Ligustrum sinense), both so abundant and successful at suppressing native flora that we see little else in the understory. They are ubiquitous in residential hedges and naturalized areas as well.

Amur honeysuckle
  • Amur Honeysuckle Don’t be lured by its fragrant blossoms and associated childhood nostalgia — Amur Honeysuckle is a habitat destroyer. Its dense thickets leaf out in February, shading out native vegetation; it is “allelopathic”, generating its own chemical that, depending on soil conditions, acts as herbicide for many native plants; and its berries are the equivalent of junk food, inadequate nourishment for songbirds in need of their native plant food sources.
  • Chinese Privet  The worst of numerous invasive privet species, Chinese Privet has a lot in common with Amur honeysuckle – a multi-strategy habitat destroyer.
  • New seedlings and smaller, young plants of both are easy to pull up with your hands. Repeatedly cutting back larger shrubs prevents their reproduction and spread. Follow the embedded links above for more control and removal guidance.
Japanese honeysuckle and winter creeper (and some determined native ferns)

Next week we’ll shift to a more upbeat topic – native flora treasures hidden in plain sight!

FOR MORE INFORMATION

Plant RVA Natives

Virginia Department of Conservation and Recreation’s Natural Heritage Program

Plant Invaders of Mid-Atlantic Natural Areas (National Park Service)

Spring’s Worst Invasive Plant Threat: Fig Buttercup

March 23, 2020 · 2 minute read
Spring’s Worst Invasive Plant Threat: Fig Buttercup

EDITOR’S NOTE: This article is the first in occasional series from members of the James River Park System Invasive Plant Task Force.

Some of the earliest signs of spring in Richmond are downright ominous for those who know how to read them. The pretty yellow flowers of Fig buttercup (Ficaria verna) are one of those unwelcome harbingers. If this early-blooming perennial has popped up in your yard, you will want to take action to prevent its spread into our urban woodlands, including the James River Park System.

Fig buttercup forms a thick mat and crowds out native species.

Fig buttercup (also commonly known as “Lesser Celandine”) is an invasive plant introduced from Europe. The USDA ranks it as a high-risk weed and several states have banned its sale. Like all invasive plants, it is highly successful at aggressively reproducing and spreading, wiping out our diverse, indigenous native plants, particularly spring wildflowers like bloodroot, spring beauty, and trout lily. The James River Park System Invasive Plant Task Force, with grant-funded professional assistance is currently treating Fig buttercup invasions in The Wetlands section of the park and needs your help to curb the spread.

Some identifying features of Fig buttercup:
 Its stems and leaves emerge as “basal rosettes” in late winter.
 It resembles common buttercup and has shiny, dark green, heart-shaped leaves with netted veins on their undersides. Yellow flowers have varying numbers of petals. You can find a detailed guide to identification here.
 Ficaria verna favors full sun and riparian zones (areas adjacent to rivers, streams, lakes,
and ponds) but also thrives in shady woods and lawns.
 It forms vast, solid mats that choke out native flowers, grasses, and shrub and tree seedlings.
 After blooming, the above-ground plants quickly disappear by late May or early June.
 It reproduces and spreads through multiple means, primarily underground tubers and bulblets.

Richmonders have an opportunity with Fig buttercup that we didn’t have with many other now dominant invasive plants like English ivy: we can check its spread and protect our park system’s urban forest and the native plant communities that struggle to survive in the midst of an overwhelming abundance of invasive plants (there are approximately 50 identified invasive plant species throughout the JRPS and they are the dominant vegetation in much of it).

Ficaria verna is far trickier to manage than vines like ivy or shrubs like privet. The treatment window is short, and management must occur in late winter or early spring. Well-intentioned removal attempts can instead contribute to its spread. Hand-digging scattered, individual plants is possible, but must be done carefully to ensure removal of all underground parts of the plant.

Treat these like toxic waste: securely bag and place in the garbage. Large infestations require the judicious use of a wetlands-approved herbicide; treatment must occur soon after the plants emerge, never late in the flowering period because of risks to native plants and amphibians, and according to specific weather conditions. Only trained applicators should undertake this work and should strictly follow the prescribed treatment for Fig buttercup. The Upstate Chapter of the South Carolina Native Plant Society and Virginia’s own Blue Ridge PRISM both provide excellent guidance.

If you would like more information about the impact of invasive plants on our park system, please visit the JRPS Invasive Plant Task Force website.