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Climate Extremes: What’s the Forecast for Invasive Species?, Webinar, January 16th

Photo: Julia Blum

Tuesday, January 16, 2024
7 pm
Webinar
Register here.

As the planet heats up, non-native species all over the U.S. are pushing north to follow the warmer weather. But the simple narrative doesn’t end there. Dr. Andy Chang, lead marine biologist for Smithsonian Environmental Research Center’s California branch, has tracked the movement of species introduced by human activity to San Francisco Bay and the California coast for the past two decades. In addition to northward and upstream migrations in warmer years, his team has also noticed species getting wiped out in years of intense rainfall. In this talk, he’ll reveal how climate change and extreme weather like droughts and floods are changing the seascape for invaders. He’ll also highlight how countries can use this knowledge to help stop nascent invasions before they get a foothold, in San Francisco Bay, Chesapeake Bay and around the world.

Tree-of-Heaven is Not Heavenly!

Photo: Plant NOVA Natives

Article by Cindy Speas, Chair, Fairfax County Tree Commission

In summer many folks travel to the Shenandoah Valley and beyond for recreational opportunities. Driving in any direction from Northern Virginia in the growing season, there is a tree that can be seen everywhere along the highways and byways. The dramatic clusters of seeds are so large they look like giant flowers among the leaves. It’s not native walnut or native sumac—it is Ailanthus altissima, commonly called Tree-of-Heaven. Disturbed areas and right of ways along roads are perfect locations for this opportunistic pest to colonize. Ailanthus is popping up in suburbia as well, and those of us who love trees wonder why experts are calling for us to remove these attractive and fast-growing specimens from our properties as soon as possible?

Ailanthus was imported from China and widely distributed in the United States as an ornamental in the late 1700s and 1800s. Its behavior, though, is far from heavenly—it spreads aggressively through root sprouting and huge seed production; it grows to maturity rapidly with a very long taproot; it is characterized by its terrible odor; and it poisons the ground around its roots with chemicals, in a process called allelopathy. This prevents native trees and plants from growing nearby, allowing Ailanthus to quickly spread and dominate our landscape.

Additionally, Ailanthus is the preferred food source for a new invasive insect—the Spotted Lanternfly (SLF). In spite of state quarantines, this destructive pest has now been found in Fairfax County. It is a major threat to some of Virginia’s agricultural areas, especially our vineyards, peach orchards and hops. It is also a threat to native tree species like oaks and maples that thrive in our yards. Forest Pest Branch asks all residents to report Ailanthus here and report Spotted Lanternfly sightings here.

Some may ask why these non-native trees should be removed—don’t they at least provide shade and shelter in a warming world? They certainly can, but they crowd out our native oaks, beeches, hickories and maples, as well as failing to provide the critical food resources that native insects and other animals need to live and reproduce in a fully functioning, healthy ecosystem. If a plant like this is killing off or threatening major parts of our local natural food web, the entire system will eventually collapse. And we will lose our native tree canopy along the way.

How can we stop the spread of this nasty invasive? The first thing, of course, is not to purchase it in the first place! So be sure to learn how to identify it. You can become familiar with the iNaturalist app on your smartphone or use other online resources to name the plant. The second is to remove the tree if it is growing on your land. This pest, however, thrives when simply cut down, so strategies must be used to kill the root system right away. There are some excellent resources to help landowners eliminate this threat safely and efficiently. Blue Ridge Prism has excellent fact sheets with details about herbicide use for this and other invasive species.

Visit Plant Nova Natives for more information about invasives and their destructive roles in our native environment. If we could eliminate a threat like the Tree-of-Heaven, that would truly be heavenly.

Party Time on the Disc Golf Course

Photo courtesy of Plant NOVA Natives

We don’t usually associate the native plant movement or a tree campaign with sports, but players at the Giles Run Disc Golf Course see it as a natural connection. Their course, about a third the size of a regular golf course, was created in 2008-2009 by the Fairfax County Park Authority on land that was formerly mowed grass around the Lorton Prison. Unfortunately, disturbed land with a lot of edge habitat is an invitation to invasive non-natives plants to move in, and move in they did with a vengeance after the prison closed in 2000. The Oriental Bittersweet vine has been particularly problematic, turning the areas next to the fairways into a tangled mess and swallowing up the native trees and shrubs as well as the players’ discs.

Most people would probably just expect someone else to fix the problem, but disc golfers turn out to be a different sort. Organizers Tommy Donelson and Kemper Pogue started recruiting players to participate in invasive removal parties, complete with music from a portable speaker. Forty or fifty club members have joined in this fun and free way to build upper body strength, clearing out large swathes of invasives. They have also recruited other volunteers to help, starting the sessions with half an hour of education before tackling the job. Altogether, they have been putting in a hundred hours in nine sessions every month, year round.

Oriental Bittersweet is a particularly troublesome plant when taken out of its native habitat in East Asia and imported elsewhere, as it was for its pretty red and yellow berries which are used for decorations. It twines around trees, strangling them and bringing them down. It curls itself into impenetrable thickets. When cut down, it simply regrows stems that can reach high up into trees to latch onto the branches and keep going up from there. Eliminating it requires either pulling it up by its roots, some of which can be several inches thick, or using herbicides.

It did not take long for the disc golfers to understand that the invasives issue on their course is just one example of a much greater threat to our ecosystem in Fairfax County and the world in general. They are planning to eventually replant with native plants and have been spreading the word about how important it is for residents to take out invasive ornamentals from their own yards and use more natives to support the struggling ecosystem. Information about garden-friendly native plants can be found on the Plant NOVA Natives website. Meanwhile, they would be happy to invite others to their work parties. They can be contacted at [email protected]. There are plenty of opportunities in other parks as well to help with invasive removal. Cold weather (within reason) is no obstacle, since this is warm work.

Biological Control of Tree-of-Heaven, VMN webinar April 18th

Virginia Master Naturalist Continuing Education, for everyone!
Thursday, 18 April 2019
12 pm
Meeting Number: 673-006-772
Link to join: Join Webinar
Link for recordings of this and past webinars:
VMN Continuing Education Webinar page

This webinar focuses on research to evaluate biological control options for the invasive tree-of-heaven (Ailanthus altissima). It is an invasive tree that causes ecological harm by displacing native plant species. It’s also known as “stink tree” due to the strong odor produced by the male flowers. You’ll hear background information on biological control and why it’s an appropriate option for Ailanthus. Additionally, the presenter will provide an update of her Virginia-based research studying a native fungal biological control agent. Come learn what this research might mean for Ailanthus control in the coming years!
Presenter

Rachel Brooks is a third-year PhD candidate in the School of Plant and Environmental Sciences at Virginia Tech studying plant pathology. Rachel is originally from New Hampshire and obtained a BS in Environmental Science from the University of Vermont in 2011. She hopes to use her Virginia Tech degree to study emerging forest health problems while also conducting outreach and education.

From Garlic Mustard to Japanese Stiltgrass: Non-Native Invasive ID and Control, Mar. 14th

A Talk by Patrick Whitehouse, Fairfax County Park Authority
Green Spring Gardens
4603 Green Spring Road, Alexandria, VA 22312
Thursday, March 14
7:30 – 9 pm

VNPS programs are free and open to the public.
No reservations are necessary for lectures
FMN members: Earn one hour CE

Invasive plants are non-native species that degrade our natural ecosystems. They can tolerate a wide range of habitats, generate many offspring, mature quickly and spread. They out-compete native species, reducing or eliminating them. This can lead to fewer native birds and wildlife.

Please join the Potowmack Chapter of the Virginia Native Plant Society for a talk by Patrick Whitehouse, an ecologist for the Resource Management Division for the Fairfax County Park Authority (FCPA) who will discuss non-native plant identification and control, as well as information on the Invasive Management Program at Fairfax County Park Authority. Patrick has worked for the FCPA first as a naturalist, then as an ecologist, earning his bachelor’s degree in Forest Management from West Virginia University.

Habitat restoration such as the Invasive Management Area (IMA) project can support the success of native plant species. The IMA Project began in 2006 and now manages more than 35 acres in Fairfax County. The Early Detection and Rapid Response (EDRR) program is another county effort that finds new invasive species through surveys, then eradicates them before they cause harm. This data on invasive species is tracked across the county. Fairfax County offers many resources about invasive plants to the general public including a pamphlet entitled Invasive Forest Plants
https://www.fairfaxcounty.gov/parks/sites/parks/files/assets/documents/naturalcultural/invasive%20forest%20plants%20brochure.pdf

and a booklet entitled, Non-native invasive ID and control https://www.fairfaxcounty.gov/parks/sites/parks/files/assets/documents/naturalcultural/non-native-invasive-id-control-booklet.pdf