Arlington Tree Canopy Remains Stable

As much as Arlington values its trees, the county is challenged by its increasing population and the development that this brings. Areas in red on the map have lost tree canopy since 2011, largely as the result of infill development.


But there is good news:  Arlington reversed the decline in tree canopy found in 2011 (40%) but has not rebounded from its first measurement in 2008 (43%).  The county’s  overall 2017 tree canopy remains fairly stable, with an increase of 1% overall. Find the Current Urban Tree Canopy Analysis here.

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A New Threat to Fruit and Other Trees

Spotted lanternfly image. Bug has double wings.Local urban foresters and naturalists are concerned about reports that a bug that can damage grapevines as well as fruit and other trees has been found in Winchester, Virginia.

The spotted lanternfly (Lycorma delicatula) was detected in Frederick County on Jan. 10,  according to Virginia Tech and the state and federal agriculture departments. The bug, a native of China, India and Southeast Asia, was found in Pennsylvania in 2010. Last year, it jumped from six counties in Pennsylvania to 13 counties and also has been found in Delaware and New York, officials said.

In Winchester, both numerous adults and egg mass were found, according to the Northern Virginia Daily. In addition, it was found at another site approximately 400 yards away. Virginia Tech Prof. Douglas Pfeiffer, who had been searching for signs of the bug, said owners of the site were cutting down and burning all Tree of Heaven (Ailanthus alsimmia), the bug’s favorite host plant for breeding.

Tree of Heaven itself is an invasive plant that flourishes in urban areas, even in sidewalk cracks when it can get a foothold. It has spindly trunks and large compound leaves. It was introduced as a fast-growing shade tree for urban areas and was at home in the novel A Tree Grows in Brooklyn, where it was a metaphor for the tenacity of recent immigrants living near it. Despite that celebrity, it needs to be removed, preferably when  young, because it out-competes native plants that provide nourishment for the local ecosystem. Read more about Tree of Heaven here.

Pfeiffer said that even with the destruction of the host Tree of Heaven, it is likely that the spotted lanternfly already has spread from the Winchester sites. Since it is potentially a very serious pest of grapes, peaches, hops, and a variety of other crops, looking for it and reporting any finds is important. The double-winged bug damages vines and trees it infests by feeding on sap in the host plants.

The spotted lanternfly “may not have a high impact on urban areas, where orchards and large fruit tree groves tend to be less common,” Arlington Urban Forest Manager Vincent Verweij said in an email Monday.  “Nevertheless, if you believe you have found evidence of this pest, please let our state forestry department (and us) know, so we can all be aware of the pest’s extent.”

Several trees found locally could be endangered by the spotted lanternfly, according to the U.S. Department of Agriculture. They include oaks, sycamore, walnut, willow, maple, pine and poplar. The USDA site, featuring several photos of the spotted lanternfly, with its wings folded and looking like a stinkbug with a spotted back, can be found here.

Alonso Abugattas, Arlington’s natural resources manager, said on his Capital Naturalist blog: “As this is an Early Detection Rapid Response invasive, please report any sightings so we can get rid of it before it gets established locally.”

Here are links for reporting sightings to the following:

Arlington Urban Forest Manager Vincent Verweij:

Arlington Natural Resources Manager Alonso Abugattas:

Alexandria Arborist John Noelle:

Alexandria Natural Resources Manager Rod Simmons:

Falls Church Arborist Katherine Reich:

Virginia Department of Forestry’s Urban Forest Conservationist Jim McGlone:

Virginia Cooperative Extension:










Read more here.

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Arlington’s Tree Canopy Fund Survey

These trees planted in 2009 are now taller than the apartment building!

In 2008, the Arlington County Board created the Tree Canopy Fund (TCF) to ensure funds contributed by developers who cannot meet tree planting requirements on their sites will be used to plant trees on other private property.  Since then, 1,686 saplings have been planted throughout Arlington under the oversight of the Urban Forestry Commission (UFC).  The program is managed by Arlingtonians for a Clean Environment (ACE) and trees are planted by a professional tree care contractor. TCF provides larger trees planted by professionals (these root balls weigh 300 – 500 pounds, and trees are 6 feet tall!), sizes more appealing to condos, apartment managers and homeowners seeking immediate impact for the front yard and sidewalks.  Since planting larger trees professionally is more costly than providing tree whips, TreeStewards were asked to conduct a tree survey in the summer of 2017 to determine the program’s effectiveness.

Over 25 Tree Stewards along with some Master Naturalists were instructed on how to score trees on the survey sheets and told not to enter private property without permission. They were assigned neighborhoods and fanned out over the entire county to search for and assess the trees planted during the last 8 years. Volunteers also distributed educational information to homeowners on how to remove ivy from trees, correct mulching and other topics.  In many cases, volunteers rang doorbells or left notes offering to discuss tree care or ask permission to enter a backyard to better rate a tree.  Other volunteers entered the data collected and assisted with the final analysis.

A recent sweetgum planting is inspected by TreeSteward Bill.

Arlington Oaks received an oak.

  • 1,372 trees or 81.3% were found by the survey volunteers. A tree that was “not found” could mean the tree could not be observed and rated because of a fenced yard or the tree location listed was not clear.  What we do know is that less than 19% of trees planted through the TCF program have died.
  • 88% of the trees found were rated in “Good” condition. This shows that most residents who have received planted trees under the program take care of their trees. Trees were planted throughout Arlington at single family homes (49%), multifamily properties (49%), and nonprofits (2%).

The Tree Canopy Fund also funds education efforts. The 2012 community education campaign to remove ivy from trees allowed Tree Stewards and Master Naturalists to hire a professional communications firm that has resulted in more than 22,000 internet visits and 5,000 pieces of printed material distributed.  In 2018, a community campaign encouraging preservation of mature trees will be conducted by Tree Stewards. Materials will be developed by the same professional communications firm and tested on Arlington homeowners focus groups in February with campaign starting in late March.

All of the Tree Canopy Fund programs depend on volunteers for their success. Arlington residents learn about the free tree offers from notices in civic association newsletters and other media, yet it is committed volunteers who go door to door encouraging neighbors and apartment managers to apply for trees that have had the best success.  Education on tree care in the community is promoted by Arlington’s active volunteers.

The  young trees planted so far under the Tree Canopy Fund programs will require decades before they can replace the tree canopy lost by the removal of large trees during development, yet it is a start.

TreeStewards select saplings for the spring 2018 planting to ensure quality trees.

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Christmas Tree Choices: Living, Cut, or Artificial

After 50 years of reuse and recycling, this artificial tree is green!

‘Tis the season in which many believe the holidays would not be complete without a decorated tree. For those who care about their own environmental impact, the good news is you can follow your traditional celebration with a clear conscious! Just remember the environmental golden rule to Reduce, Reuse, and Recycle whatever your choice. Below are points to consider:

Artificial Trees create a larger carbon imprint at the beginning, yet with yearly reuse and not purchasing new models, this can be spread out over a long time.  The tree to the left is basically a wooden pole with green wire bristles from 1960 – so old it is now chic, and holds 50 years of family history. Continue reading

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Add a Free Native Tree

Sassafras albidum

Sassafras albidum

Trees have many benefits. They provide shade, beauty and tranquility, cool the air, soak up greenhouse gases, emit oxygen, and help to shelter and feed birds and other wildlife. Native trees are especially important because they can support a huge number of native insects and caterpillars, which is what songbirds feed their young. Caterpillars also turn into beautiful butterflies and moths.

So if you can do only one thing for nature, plant a native tree. Or, if you live in Arlington, have one planted on your property at no cost to you through the Tree Canopy Fund.

Attend a meeting from 7 to 8:30 p.m. Monday, Nov. 6, at Shirlington Library, 4200 Campbell Ave., Arlington, to learn more about the tree canopy fund and how you can apply for a robust tree to be planted on your property next spring. The application deadline is Dec. 15, 2017.

For a list of the 11 available species followed by photos and additional descriptions of each tree, click: TCF 2018 Spring Species

Tree Stewards will help you select the right tree for the right place right at your home.

Posted in ACE, Education, Events, Free Tree, Tree Canopy Fund | 1 Comment

The Silent Killer in Your Yard

What’s scarier than bumping into a spider web, a witch, a black cat or a bat in the dark of All Hallows Eve?

It’s a zombie plant that harbors rodents and mosquitoes on the ground but morphs into a killer of earth’s largest living ancient species when it climbs and matures. Still stumped?

It’s English ivy, which can choke – and kill — the beautiful trees that give our yards and neighborhoods shade and character. What looks like a lovely little green plant can clamp onto trees, accelerating rot, and causing mature trees to fall down during storms.

Ivy can strangle trees, and once it is in the tree canopy, it can block sunlight from the trees’ leaves. Dense ivy cover deprives the tree’s bark of normal contact with air and microorganisms and competes with the tree for nutrients and water. Ivy is a threat. But we can beat it with simple landscaping work.

3 Steps to Remove Ivy from Trees

1. Use garden clippers to cut ivy at the bottom around the entire trunk of all infested trees. The goal is to separate all ivy vines from their source of nutrients in the soil so they will die. If the ivy is not dense, you can pull it from the soil at the bottom of the tree with your hands, especially soon after it rains. On heavily infested trees with ivy vines thicker than an inch, you will need to carefully saw through the vine and carefully, gently ease it away from the bark. Experiment with the tools below to find what works best for you.

TIP: Wear gloves and long sleeves to lessen the risk of poison ivy. Many prefer doing this during the winter months when poison ivy is less virulent, and they will have heavier clothing to reduce the risk.

2. Pull all ivy vines out of the ground around the base of the tree, making a “life saver ring” 2 feet wide all around the tree. This will protect the tree from future infestations. This is easiest to do when the soil is soft from rains; if the ground is very hard and the vines keep breaking, wait until after a rain to remove the vines. The cleared space allows you to see any emerging ivy from roots you missed. Arborists suggest laying a 2″ thick leaf or wood chip mulch for three feet around the tree to preserve moisture in the soil and keep lawn mowers from getting too close to the roots. Keep the mulch 3″ away from tree trunk to ensure air exchange for the bark, and you can spot any ivy trying to reinfest the tree.

3. Once cut, leave ivy on the tree. Do not pull it off because that could harm the tree. Ivy will gradually blend into the tree bark after it is cut. Check up your tree each winter to be sure the ivy remains off.

Please note that ivy’s leaves grow larger and more heart-shaped as the vine climbs up the tree. This mature phase of the plant produces flowers in late summer and purple berry-like fruit in autumn that birds eat and spread far from the initial source. If you’re uncertain about the identity of the vine on your tree, track a stem of it back to ground level until you are certain it’s English ivy. Then follow the steps above to kill its vines on the tree trunk.

Please contact the TreeStewards at to get a demonstration of how to remove ivy from a tree in your yard or to request a speaker.

Additional Education Material

Download 2-sided mini poster about ivy removal.

This was developed for TreeStewards and Arlington Regional Master Naturalists under a grant from the Tree Canopy Fund of Arlington, Virginia. These materials, created by the Biodiversity Project of Chicago, may be adapted and distributed by anyone who wants to protect their trees.
We’d like to know how the campaign is succeeding. Please notify us when you clear ivy from trees or if you are using the materials in your work by emailing

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