Invasive Species: Natural World Bullies

The Teal Trail near Westville is a horror show of invasive plant overgrowth. This picture from July 2017 is AFTER I spent four hours cutting back a quarter mile section of trail. I began targeting this area in November 2019, systematically cutting down the invasive plants. Through July 2022, I have spent 265 hours clearing the invasives from this area with another 75 hours contributed by others. We have completed the end of the first phase of cutting back the "old growth" invasives. In the meantime, the invasives are aggressively resprouting. If invasive species are not targeted, over time the entire park could look like this. There is almost no new tree growth in this area because the saplings are choked off by the invasives. When we cut back the invasives, we find one to two foot tall native trees, including ashes, oaks and maples.
Invasive offenders include privet (a hedge from Europe), multi-flora rose (a sharp-thorned shrub), Asiatic bittersweet (a vine that twists around trees and strangles them), Japanese honeysuckle (a vine that creates a dense mat of vegetation), Amur honeysuckle (a wide spreading shrub),  winged euonymus (burning bush, a shrub with corky "wings"), and wineberry (a Japanese raspberry with a hairy red stem).

By August 2021, the Teal Trail looked somewhat more under control, as the invasive plants were cut to the ground, and had not aggressively regrown. They continue to resprout and need regular cutting to keep the trail open.

Why Invasive Species Should Matter to Park Users

Why should you care about invasive species in the woods? 

These are a few good reasons, all of which detract from your experience in the woods:

• Invasive plants are typically the reason a trail can become quickly overgrown and difficult or impossible to follow, sometimes with sharp thorns that tear at your clothes and flesh.
• Invasive plants also create a dense underbrush that is a perfect habitat for small rodents carrying ticks. Particularly when that invasive is Japanese barberry, the more invasives, the more ticks and the greater chance of getting Lyme Disease and other tick-borne illnesses.
• Bittersweet and honeysuckle vines strangle trees and will eventually pull them down, partially or completely blocking trails.
• Invasive plants displace desirable native plants. Winged euonymus and autumn olive will crowd out blueberry and huckleberry bushes. Mugwort and wineberry leave no room for blackberry and raspberry bushes. Phragmites displace cattails in marshy areas.
• Another reason to have an interest in removing invasive plants: visit the wildflower page on this website and imagine that page as a memorial to plants that no longer exist at the park. Fortunately, that is not the case, but it could happen if the invasives are allowed to spread.
• If you are bird lover, know that while our feathered friends will eats berries from invasive plants (thus contributing to their spread), these berries are typically a poorer food source for the birds than the native berries, with a high sugar content (junk food for birds) as compared to the high fat of some native berries.

New England woods should have a "clean" look to them with clearly defined plants of all sizes. If the woods look like a dense jungle with green things growing everywhere, you are probably seeing an area heavily impacted by invasive plants.
Invasive plants can be viewed as natural-world bullies, the kind of thugs that if they were human would be knocking you down and stealing your lunch money. 
West Rock has its share of problems caused by these non-native, non-desirable species.

Briefly, an invasive is any animal or plant that is not native to an area, and was usually brought here by people who thought introducing such a species was a good idea. Most invasive plant species come from Asia and Europe.

This article is an excellent explanation of how invasive plants became such a problem: http://poison-ivy-patrol.com/brief-history-invasives/

The website has articles about some common invasive plants. I disagreee with the recommendation to cut native, wild grapevines. They co-exist well with the trees at West Rock where I have never seen them cause a problem, as compared to the bittersweet vines that I have seen wrapped around many a fallen tree.

This page is not a comprehensive list of invasive species, nor it is a complete list of invasive species at West Rock, only a list of the most common and widespread invasives.
How seriously does Connecticut take this issue? Seriously enough that is against the law to import, move, sell, purchase, transplant, cultivate or distribute these species discussed on this page: the Asiatic bittersweet vine, the Japanese honeysuckle vine, multi-flora rose, autumn olive and Russian olive, and garlic mustard. Japanese barberry and winged euonymus are common landscape plants sold in nurseries and garden centers.

This website details many common invasives in a booklet format: https://cipwg.uconn.edu/wp-content/uploads/sites/244/2016/12/Invasives_guide_2016_web.pdf

If you are thinking of controlling invasive plants, my most important rule: Know what you are cutting! Well-meaning people can do far more damage than good if they mistakenly cut native shrubs thinking they are invasives. I tell people who help me, "I can always return and cut an invasive you missed. I can't replant something native that you cut."

This area adjacent to the Teal Trail near Westville, as seen in January 2015, shows the "messy" look created by invasive plant overgrowth as they overrun and choke out native and desirable plant species.

Invasive Plants

Invasive plants all share certain characteristics, which is why they are invasive. These plants tend to grow quickly, and grow in many habitats, crowding out native species. They often have leaves earlier in the spring and later in the fall than native species. They can create dense shade, which makes it difficult for native species to survive in their shadows. They are prolific seed producers, seeds which are spread by birds that eat them. They often grow in areas where native plants grow thinly, or not at all, such as dense forests or rocky slopes.

If you cut them, they grow back even faster. They are even resistant to chemical control. I do not mess with chemicals, so all of my methods are mechanical. Most invasives are found near the edge of the woods where there is more light and where the birds that spread them tend to congregate.

Some people have asked me, “What’s the point?” and “Are my efforts making a difference?” My belief is that we have already lost the war, but we can win battles, reclaim areas, and slow the spread of these invasives. In a worst-case scenario, there will few woods left if we do not control the invasives, as they will choke out the growth of new native trees and shrubs.

Another common question regarding invasives is "How did they get here?" In most cases, someone traveling to another country saw a plant they liked and brought back a sample for a home garden. Once removed from their native environment where the species grew in competition with others, and likely had natural predators to keep it in check, these plants can displace and outcompete native species.

The areas at West Rock most afflicted and overrun by invasives include the Red-White and Red Trail by Farm Brook Reservoir off Hill Street, the gravel road portion of the Red Trail south of this pond, the Teal Trail near Westville, the Red Trail along the Wintergreen Brook north of Lake Wintergreen, and Baldwin Drive.

The Red Trail north of Lake Wintergreen is nearly closed off by fast-growing plants in Aug., 2017, despite having been thoroughly pruned back in March 2017. Assorted invasive plants are responsible for most of the growth. I pruned this back in Sept. 2017, but did not take an "after" picture of that work. The state used a brush hog to cut back the trail in Aug. 2024.

The Nov.-Dec. 2015 issue of Connecticut Wildlife magazine (published by the Department of Energy and Environmental Protection) had an article called “Whip-poor-will Inventory and Monitoring 2010-15 Summary”, written by Shannon Kearney-McGee, DEEP Wildlife Division, that gives a specific example of how invasive plants negatively affect birds.

The article on page 15 talks about how the whip-poor-will bird is in severe decline in Connecticut due to various factors including development and invasive plant species. The article states, “Only one of the 11 locations (9%) that contained whip-poor-wills also contained invasive species, while 11 of 26 locations (42%) where whip-poor-wills were not detected contained invasive species. This is significant because invasive plants have been shown to produce fewer moths and butterflies than native plants. Moths and butterflies are an important food source for whip-poor-wills.” The full article may be read online at 

https://portal.ct.gov/-/media/DEEP/wildlife/pdf_files/outreach/connecticut_wildlife_magazine/cwnd15pdf.pdf

Other sources write about how berries from invasive plants are junk food for birds because they are high in sugar, but birds need berries that are high in fat. This article discusses Amur honeysuckle, which is native to China. In addition to its high sugar berries, this shrub is linked to increased numbers of mites, ticks and mosquitoes. Article: https://theoec.org/blog/amur-honeysuckle-lonicera-maackii/

This article provides details on how native shrubs provide better nutrition for birds: https://howardmeyerson.com/2016/09/17/invasive-plants-and-birds-research-shows-native-plants-are-better-for-nutrition/

Invasive Plants and Lyme Disease

The state of Connecticut has been studying Lyme Disease and has made a definitive connection between the presence of invasive Japanese barberry in the forest and the number of Lyme-disease carrying black legged (deer ticks). Essentially, barberry is the ideal habitat and breeding ground for these disease-carrying ticks. The more barberry in an area, the greater number of ticks: 120 ticks per acre in a barberry-infested forest vs. 10 ticks per acre in a barberry-free forest. I cannot think of a more compelling reason to control barberry.
Fortunately, West Rock does not have a significant barberry problem. There are isolated patches of it, but West Rock does not have the vast swaths of barberry that carpet some hiking areas.
In 2014, I helped out on an invasive clearing project at Sheffield Island, off the Norwalk coast, and spent an hour cutting up barberry in an off-trail area blanketed with the prickly stuff. I emerged from the area absolutely covered with ticks, about 80 by my estimate.

Despite repeated checks and removing many crawling ones from my clothes and skin, I missed one and caught it as dropped off me a week later, fully engorged. I had it tested by the state and it was identified as a lone star tick, which does not carry Lyme Disease. However, some people who have been bitten by the long star tick have developed an allergy to eating red meat. Thanskfully, they did not happen to me. If you go to Sheffield Island, stay on the gravel paths!
Another plant that has been linked to tick populations and therefore Lyme Disease is Amur Honeysuckle, a shrub with flaky, tan-colored bark. There are scattered examples of this shrub at West Rock. By contrast, the boardwalk by Little Pond at White Memorial Conservation Center in Litchfield, and the accessible portion of the Appalachian Trail in northwestern Connecticut are lined with this shrub.
These are some good articles with more details about the barberry-tick-Lyme Disease connection:

The Connecticut Agricultural Experiment Station (CAES), which has been doing the research on this topic published a guide in February 2013 called Japanese Barberry Control Methods: Reference Guide for Foresters and Professional Woodland Managers, written by Jeffrey S. Ward, Chief Scientist for CAES; Scott C. Williams, Associate Scientist for CAES, and Thomas E. Worthley, Association Extension Professor, University of Connecticut. The guide presents an overview of the barberry-tick link and has detailed information about how to control it. This guide is very useful for homeowners as well. Website: https://portal.ct.gov/-/media/CAES/DOCUMENTS/Publications/Special_Bulletins/SpecialBulletinFeb2013Wardpdf.pdf

Williams, Ward and Megan S. Linske published a research article on this topic entitled Long-Term Effects of Berberis thunbergii (Ranunculales: Berberidaceae) Management on Ixodes scapularis (Acari: Ixodidae) Abundance and Borrelia burgdorferi (Spirochaetales: Spirochaetaceae) Prevalence in Connecticut, USA available here: https://academic.oup.com/ee/article/doi/10.1093/ee/nvx146/4159248/LongTerm-Effects-of-Berberis-thunbergii

The Rise of the Tick by Carl Zimmer, published in Outside magazine, April 30, 2013, is an informative look at the work by these scientists in studying the barberry-tick connection. Website: http://www.outsideonline.com/1915071/rise-tick

Controlling Japanese Barberry Helps Control Ticks by Sheila Foran in UConn Today, on Feb. 22, 2012, also describes the work of these scientists: http://today.uconn.edu/2012/02/controlling-japanese-barberry-helps-stop-spread-of-tick-borne-diseases/

Managing Exposure to Ticks on Your Property, a guide written by Kirby C. Stafford III, Ph.D, chief entomologist for CAES, does not discuss barberry, but provides tips to create a property that is not favorable to deer and ticks. Website: https://portal.ct.gov/-/media/CAES/DOCUMENTS/Publications/Fact_Sheets/Entomology/TickControlFSpdf.pdf?la=en

Invasive Shrub Increases Risk of Human Disease (via Ticks, Deer and Bacteria) is an article published Oct. 10, 2010 by Ed Yong on the National Geographic website, discussing the way amur honeysuckle creates a favorable habitat for ticks. Website: http://phenomena.nationalgeographic.com/2010/10/11/invasive-shrub-increases-risk-of-human-disease-via-ticks-deer-and-bacteria/

Native blackberries ripen in Aug. 2017 on the Regicides Trail near the Purple-Orange Trail. Many blackberry plants grow along the Regicides Trail, but in other areas are displaced by thorny multi-flora rose, an undesirable invasive plant.

Invasive Plants vs. Natural Alternatives

These are lists of common invasives and West Rock and the preferred natural alternatives that are displaced by invasive plant species.

• Oriental bittersweet and Japanese honeysuckle vines vs. Concord grape vines (You can eat grapes, but not bittersweet berries).
• Autumn olive and Russian olive vs. witch hazel, spicebush, and winterberry (Witch hazel, spicebush, and winterberry are attractive shrubs that peacefully co-exist with other native plants).
• Winged euonymus and privet vs. high-bush blueberry (You can eat blueberries, but not euonymus or privet berries).
• Multi-flora rose and wineberry vs. raspberry and blackberry
  (You can eat raspberries and blackberries. Yes, you can eat the rose hips from multi-flora rose and the berries from wineberries.)
• Japanese barberry and Japanese knotweed vs. low-bush blueberry and huckleberry (You can eat blueberries and huckleberries). Admittedly, you can eat the young sprouts of knotweed, which I am told is similar to asparagus and ironically is a potential treatment for Lyme disease.
• Garlic mustard and mugwort vs. native wildflowers (Yes, you can eat garlic mustard, but I prefer the native wildflowers).
• Phragmites vs. cattails (Cattails are an important food source for animals, but phragmites have nothing to offer them.)

This tree was blazed in April 2012 on the Teal Trail, and in the two years that followed, the blaze became covered by a combination of invasive species: Asiatic bittersweet and Japanese honeysuckle vines, and the shrubs multi-flora rose, and privet.

This tree was temporarily liberated from its captors in Jan. 2015.
It died in 2017 and I cut it in pieces after it fell across the trail.

Invasive Vines

Asiatic Bittersweet Vine

Asiatic bittersweet gets my vote for the most devastating species at West Rock. This vine has a round stem with dark brown bark when young that is light brown as it grows larger. The leaves are heart shaped with a medium green color and the leaves drop off in the fall. This species is easily distinguished by the fact that it wraps itself around trees and strangles them. Even before it strangles trees, its leaves will overgrow the canopy of the tree and shade out the leaves. In the winter, it has red berries hanging, waiting for birds to eat and spread them.

This picture taken in Jan. 2015 on the Teal Trail dramatically shows how a bittersweet vine wraps around one tree while it continues to grow toward another. Note the grooves in the bark where the tree continues to grow around the vine. Eventually the vine would strangle the tree, but I cut the vine, allowing the tree to survive.

Even more dramatic is this view of a bittersweet vine stretching across multiple trees along the Red Trail near Farm Brook Reservoir.

Multiple vines encircle a tree.

A close-up of one vine around that same tree.

A close-up of this small bittersweet vine shows its distinctive orange roots. Desirable and native Virginia creeper with its clusters of five leaves climbs the rocks in the background.

An invasive bittersweet vine with an estimated diameter of four inches hangs from a tree near the apartment buildings off the Teal Trail, before being cut in May 2021.

Feel free to take these berries for your winter arrangements. Just be sure to keep the arrangement inside, and dispose of them in your trash where they will head for the incinerator and certain death, and not in your yard, where you will further contribute to the spread of the problem.

In the woods, the Asiatic bittersweet creates a “messy” look as it hangs on trees, pulls them down, and leaves a jumbled pile of wood in its wake. They have a dark brown, smooth bark when young, and a beige-colored smooth bark when older. If you pull them out by the roots, the roots are orange.

Asiastic bittersweet is very different looking than the native grapevines and poison ivy. Grapevines have a dark brown flaky bark and they have distinctive “elbows” or bends in their stems. Grapevines will hang from the trees, but will not wrap themselves around the trunks. In the summer, clusters of grapes appear, green to start and then ripening to a dark blue-purple.

Native but obnoxious poison ivy clings to one side of a tree trunk and has a “hairy” look that is caused by its external roots. The leaves are shiny and grows in clusters of three.

The native Virginia creeper grows up the side of a tree with a dark brown bark and has clusters of five leaves.

My method of dealing with bittersweet depends on the size and location. Vines of less than an inch in diameter can be pulled from the ground, tearing up plenty of soil, and exposing their telltale bright orange roots. I push back and tamp down the dirt with my boot. If the vines are growing into shrubs and trees, I will cut them as high as I can reach. If they are growing around the trunk of a shrub or tree, I will cut them in sections to free the tree.

For larger vines, I will cut them at ground level and again as high as I can reach. This approach serves several purposes. The vine will resprout from the side of wherever it was cut, so the lower the vine is cut, the less there is to grow back. Cutting high removes more weight and relieves some of the burden on the tree. Further, when the vine resprouts it may grab onto the previously cut portion, and the more space between the root and the remaining vine, the longer this process will take. Finally, when I see a large gap in the vine, I know it has been cut, as compared to if someone made one cut.

This method immediately removes the threat to the tree (if it is not already wrapped too tightly), and also diverts the plant’s energy from making seeds (and therefore more vines) to growing more vines. Since cutting does not kill it, I have to return in future years to continue to cut it.

While it may be tempting to pull down the vines from the tree, I advise against this practice. The vines tightly wrap themselves around the branches and trunk and pulling on them is unlikey to dislodge them. A strong tug may snap a branch and pull it down on your head. I just leave the cut vines that are above my head and over a few seasons they will rot and drop to the ground.

More information at https://www.ecolandscaping.org/02/landscape-challenges/invasive-plants/asiatic-bittersweet-vine-an-exotic-invasive-plant-fact-sheet/

Asiatic bittersweet hangs from a tree on Baldwin Drive at West Rock. The vines twine amongst themselves. I cut them after I took this picture.

This is a close-up of Asiatic bittersweet vines hanging from a tree on Baldwin Drive.

Asiatic bittersweet creates a wall of leaves as it hangs from trees on Baldwin Drive at West Rock, shading out the tree and other plants.

Another look at how Asiatic bittersweet hangs from a tree on Baldwin Drive at West Rock.

Japanese Honeysuckle Vine

Another invasive vine at West Rock is the Japanese honeysuckle vine. When the honeysuckle vine is young, it resembles a brown thread. As it matures, it looks exactly like twine with regard to its tan color and rough texture from multiple strands. The honeysuckle will also keep its leaves year-round, unlike the bittersweet vine that drops it leaves in the fall. Like Asiatic bittersweet, the honeysuckle wraps around a tree or shrub and strangles it over time. The honeysuckle will also blanket an area, completely smothering everything underneath it

I have seen this in various locations along the Regicides Trail, particularly between the South Overlook and Judges Cave, and near a crossing of Baldwin Drive at the northern end of the park. This vine is also engulfing the Teal Trail and the Westville Feeder near Westville. 

Honeysuckle is harder to remove than bittersweet because the honeysuckle will spread widely along the ground and when pulled, the smaller vines break, leaving the roots intact in the ground. The honeysuckle also grows back quickly. I combat this vine through a combination of pulling and cutting.

This article explains the difference between the native trumpet honeysuckle and the invasive variety: https://homeguides.sfgate.com/identify-japanese-honeysuckle-vs-american-honeysuckle-91276.html
More information at https://www.lewisginter.org/japanese-honeysuckle/

This close-up of a young Japanese honeysuckle vine in Dec. 2014 on the Westville Feeder Trail shows the thin, brown stems of the young plant and the fact that it retains its leaves in cold weather.

This is a wider view of the Japanese honeysuckle vine on the Westville Feeder  in Dec. 2014, showing how it envelops a hapless native shrub.

An invasive Japanese honeysuckle vine blooms on the Green Trail just north of Judges Cave in June 2022.

Porcelain-Berry

I started seeing porcelain-berry in 2023 at West Rock along the Teal Trail near the climbing wall and in 2024 on the Lake Wintergreen dam. Porcelain-berry has beautiful berries that range in color from blue to purple to pink, but, like other invasive vines will quickly blanket an area. The native grape vines have a dark brown, woody bark, but the porcelainberry has a green bark.

These websites have pictures and detailed information:

https://vnps.org/unwanted-unloved-porcelain-berry/

https://www.invasive.org/weedcd/pdfs/wgw/porcelainberry.pdf

Porcelain-berry blankets the rocks on top of the Lake Wintergreen dam on Aug. 13, 2024.

Wisteria

There is a patch of wisteria on the Purple Trail at the gate by Main Street that has been there for years. It presumably was seeded from a nearby yard. I have cut this at times, but have not yet gotten there as of November 2024, to do a comprehensive cutting and uprooting.

Chinese wisteria grows counterclockwise according to two websites I checked and another website says it grows clockwise. Japanese wisteria grows clockwise according to these two websites and the third says it grows counterclockwise. Either way, this vine is invasive and destructive.

Chinese and Japanese wisteria: https://www.mfc.ms.gov/forest-health/invasive-plants/chinese-japanese-wisteria/

Chinese wisteria:

https://www.invasive.org/alien/pubs/midatlantic/wifl.htm

Japanese wisteria: 

https://www.invasive.org/alien/pubs/midatlantic/wisi.htm

Wisteria covers the gate on the Purple Trail at Main Street on Oct. 29, 2022.

The wisteria vine wraps clockwise around the gate and post on the Purple Trail at Main Street on Oct. 29, 2022.

Other Invasive Vines: Mile A Minute

I thankfully have not seen mile a minute vine at West Rock.

Invasive Shrubs

Autumn Olive and Russian Olive

Autumn olive and Russian olive are an attractive shrub/small tree from Asia that grows to about 15 feet high. I have seen only autumn olive at West Rock and there are many examples of it. I have seen these shrubs with trunks as thick as 5 inches. They have a light-gray bark, thorn-like protrusions about an inch long, and grow a round berry about the size of a blueberry.

Autumn olive has a pale red berry and the Russian olive has a light green berry. Their branches grow at an angle from the trunks, so they lean in all directions. They keep their leaves until past the first frost, so they get an extra month of growth. They shade out other species, particularly the native mountain laurel.

When I cut these down, I am amazed by how much more light gets into the forest. The state hired a contractor in winter 2008-09 to cut back the autumn olive in fields by the Lake Wintergreen parking area, and off the gravel road by Mountain Road that leads to Farm Brook Reservoir (the fishing pond off Hill Street). The contractor chemically treated the stumps, and the state mows these fields annually, so the autumn olive has not regrown. However, autumn olive is spreading through the woods by the gravel road portion of the Red Trail near Farm Brook Reservoir.

Autumn olive along the Red Trail near Mountain Road, visible on the right as the green shrub. There is a patch of autumn olive I cut every year and every year, it resprouts. Over time I am making progress at holding down the spread of autumn olive in this area, since shrubs that put their energy into resprouting are not growing seed-producing berries.

There are extensive areas of autumn olive remaining near the water tank on the slope of the ridge (which the trails crew cut in April 2015 and April 2016 with help from Quinnipiac University students as part of the annual Big Event). The Regional Water Authority, which owns the land around the water tank, followed up and clear cut the area in front of the fence, along the Blue-White Trail. The vines are resprouting quickly in this clear area with plenty of sunlight.

There is much autumn olive on the Red Trail extending about 1/2 mile south of the northern section of Mountain Road. There is also plenty growing along Baldwin Drive, but far less than there used to be as volunteers have been cutting it down over time. The fields by Farm Brook Reservoir are lined with autumn olive, although many were cut to create the Red Trail along the water. I continue to cut this autumn olive and cut the resprouted plants as I return to the area for additional work.

When I cut back autumn olive, I can return a month later to find multiple thin stems extending from the trunks, as it seeks to regrow. As with other invasives, by cutting it back, I have slowed its growth, interrupted its seed producing potential, and given native species a chance to grow. I have had good success in killing autumn olive through repeated cutting.

The autumn olive berries can be eaten, not that I have tried them, and can be made into a jam, not that I have tried that either, so feel free to pick as many as you like. They are not the best food source for birds because they are high in sugar.

More information for Russian olive at https://woodyinvasives.org/woody-invasive-species/russian-olive/
More information on autumn olive:

http://www.in.gov/dnr/files/Autumn_Olive.pdf

A large autumn olive shrub grows in all directions on Baldwin Drive at West Rock.
When cut, the shrub will vigorously resprout from the base.

This picture of autumn olive along the Red Trail near Farm Brook Reservoir
shows how vigorously this shrub resprouts when cut.

A medium-sized autumn olive shrub on Baldwin Drive at West Rock.

A close-up of the autumn olive leaves show
how they are lighter green on the bottom than on top.

Autumn olive has a pale flower in the spring.

Multi-Flora Rose

Multi-flora rose gets my vote for the most obnoxious invasive. This shrub can grow to 15 feet tall, and have stems that dangle over trails, with sharp angled thorns just waiting to catch an unsuspecting hiker or biker. If you get caught in one, it can shred your skin as you try to escape. As I cut them, I often get snagged. Sometimes the thorns break off in my skin and I have to dig them out with fined pointed tweezers.

These shrubs are tricky to cut back because of the way they grow, angling in a circular way from a center stem. I find that I have to cut off the stems and work my way into the bush to reach the main part of the bush where I cut it at the base. Regrettably, this does not kill the bush, but it certainly does ruin its day. They are tough to control because they aggressively and quickly grow back. The best mechanical strategy for killing a particular bush is to cut the center root ball or break it apart and pull it out with a pick mattock.

There is a stretch of the Red Trail heading north from Lake Wintergreen where I spent time in the winter cutting back multiple multi-flora rose bushes. When I returned in the spring, it looked as if I had planted the stuff, there were so many remaining. Still I believe in the importance of this work because over time they will completely choke out an area, making it impassable.
More information at https://woodyinvasives.org/woody-invasive-species/multiflora-rose/

Sharp-thorned multi-flora rose grow small white flowers in June. The native serviceberry shrub that it displaces also grows white flowers, but in April.

Winged euonymus

I have found winged euonymus or burning bush throughout West Rock, but particularly in the Judges Cave area, near the West Rock tunnel ventilation shaft, and along the northern part of the Regicides Trail. They also grow in great number along portions of Baldwin Drive and Regicide Drive. I have seen some as tall as 12 feet with a spread of 12 feet.
The greatest number seem to be along the lower portion of the Westville Feeder, despite a multi-year battle that has pulled up hundreds of them. This plant can create a carpet of other shrubs from the numerous seeds it produces, completelly blanketing an area. The smaller ones can easily be pulled out by the roots, leading to their certain demise.
There is a fairly extensive problem with this plant at the nearby Bishop Estate/Darling House Trails in Woodbridge and I can only hope it stays off the ridge. I have occasionally cut winged euonymous on that property.
This is a popular plant in landscaping, especially at shopping centers, because the leaves have a vibrant red color in the fall, and the plant itself is hard to kill. They are fairly easily recognized by the cork-like “wings” along the branches that give the plant its name. Native blueberry shrubs also have red leaves in the fall, although not as bright, but provide delicious blueberries in July.
More information at https://woodyinvasives.org/woody-invasive-species/winged-burning-bush/

Winged euonymus becomes a beautiful red color in the fall, plus it is a hardy shrub, which is why this is so popular in landscapes, particularly at shopping centers. The problem is that it outshades and outgrows native shrubs like blueberry.

This close-up of the winged euonymus shrub shows its cork-like "wings" along the stems. These "wings" are not always visible, especially on young shrubs.

This euonymus shrub grows in the leaf litter and dirt on Baldwin Drive. This photo shows its cork-like "wings" along the stems.

This close-up of the winged euonymus shrub on Baldwin Drive shows its cork-like "wings" along the stems. These "wings" are not always visible, especially on young shrubs.

A winged euonymus plant along the Sanford Feeder Trail. This plant outcompetes the native and desirable high bush blueberry plant, which also has red leaves in the fall.

Invasive winged euonymus grows along the edge of Baldwin Drive near the Purple-Orange Trail, blanketing the area and displacing virtually everything else that is trying to grow. Its bright red color, as seen in November 2021, makes it easy to spot for removal.

Native huckleberry seen here along the Purple-Orange Trail in November 2021, turns a muted red in the fall and is a native shrub that is displaced by the invasive and aggressive winged euonymus.

Privet (European and Chinese)

Fans of Harry Potter recognize the name privet, which is the name of the street where the fictional English lad lives. Privet is a common hedge in the United States that can easily grow 20 feet tall. The shrub has a light colored bark, medium green oval shaped leaves that it drops in the fall, and small bluish-black berries in the fall and winter. In the woods, privet creates a dense thicket in which other plants cannot survive

Privet is found at West Rock along the Teal Trail near Westville, at the top of the Red Trail by the South Overlook, along the Blue Trail near the pavilion, and in the woods behind Judges Cave by the Green Trail. I found a small patch on Baldwin Drive. I pull smaller shrubs and cut larger ones. We have been extensively cutting these areas, but it grows back agressively.

More information on European privet at http://www.invasive.org/eastern/srs/CP_EP.html and on Chinese privet at http://www.thejump.net/hunting/plant-id/chinese-privet.htm

Chinese privet flowers along Baldwin Drive, June 2014.

Chinese privet crowds the Red Trail by the South Overlook in June 2017.

The Red Trail by the South Overlook in June 2017 after the privet had been cut back.

Japanese barberry

Japanese barberry is a shrub that has round stems with thin, needle-like spines, small round leaves, and shiny red oval berries. When cut or pulled, the distinctive bright yellow stems and roots can be seen. Bayberry can survive in heavily shaded areas. An important reason to remove barberry is because it creates a habitat that ticks prefer, not to mention the discomfort of being stabbed by the pointy spines.

Barberry is less of a problem at West Rock than it is in other hiking areas where you can literally see a carpet of barberry as far as the eye can see. At West Rock, I find isolated patches of barberry, especially along the edge of Baldwin Drive. There are some extensive patches of barberry on adjacent water company land along the Sanford Feeder Trail.
This is a relatively easy invasive to kill because smaller shrubs can be pulled up by the roots. When they are too large to pull up, I cut them. The roots can also be dug out with a pick mattock. If there are berries on the plant, I collect them and put them in the trash to prevent even more barberry growth. 

More information at https://woodyinvasives.org/woody-invasive-species/japanese-barberry/

Amur Honeysuckle, Morrow's Honeysuckle and Bell's Honeysuckle

There are different varities of invasive honeysuckles, most of which are from Asia. Names include Amur honeysuckle, Morrow's honeysuckle, and Bell's honeysuckle. This shrub can grow to 15 feet tall and equally as wide, growing in all directions from a center stem that has rough, woody bark. In spring, it has yellowish-white flowers (sometimes pink). In summer it has small red berries. Invasive honeysuckle can be distinguished from the native varieties by the hollow center in the stem.

I have seen this in scattered places at West Rock. On the handicap-accessible portion of the Appalachian Trail, invasive honeysuckle can be seen everywhere, completing taking over everything by the trail itself. Only through the efforts of volunteers is the trail being kept clear of this unwanted shrub. I have also seen this along the Mill River at East Rock Park.

There is more information on theses websites:

Amur: https://www.invasive.org/alien/pubs/midatlantic/loma.htm

Morrow's: https://www.invasive.org/alien/pubs/midatlantic/lomo.htm 

Bell's: https://www.mda.state.mn.us/plants/pestmanagement/weedcontrol/noxiouslist/bellshoneysuckle

Invasive Trees

 

Tree of Heaven

I learn about invasive species over time, sometimes by reading about them on websites that list common invasive plants. Other times I observe prolific amounts of a plant in the woods, and then asking a knowledgeable person about them or reading about them online.

The tree of heaven is an invasive that I learned to identify in 2020, and immediately began targeting it by cutting it down. Tree of heaven is native to China and is the preferred habitat for the spotted lanternfly, a destructive insect making its way toward Connecticut in 2019 and later.

When mature, the tree has a light-colored bark with a texture that resembles a cantaloupe. The branches are concentrated at the top of its straight trunk. Its narrow, pointy leaves give it a tropical look. When cut and thankfully the wood is easy to cut, the tree gives off a disgusting, choking smell that lingers in the air and can be described as similar to the stenchy from an overheated clutch or brakes. The stench more politely be described as burnt peanut butter.

The tree of heaven is similar to the native staghorn sumac, but there are a number of distinguishing features. The sumac has the appearance of a shrub with branches that grow in many directions. The upper branches have a fuzzy coating to them, which is where the name staghorn originates. The sumac leaves are serrated, while the tree of heaven leaves are smooth with a bump out near the base. The sumac leaves turn a brilliant red in the fall, while tree of heaven leaves turn yellow. Finally, the staghorn sumac will grow a fruit that is bright red and roughly the size and shape of a pinecone. Due to the smell it generates when cut, the tree of heaven has the nickname stinking sumac. This invasive will also resprout vigorously when cut, making mechanical control a challenge.

This website clearly shows the difference between tree of heaven and the native stag horn sumac: https://bplant.org/compare/318-1228

Small tree of heaven specimens grow in patches of soil along the rocky slope above the Teal Trail in May 2021 and were uprooted after this picture was taken.

There are three places along Baldwin Drive where I have seen patches of tree of heaven: by the second switchback curve near the West Rock Tunnel air shaft, partway up the road between the Orange and Blue-White Trails and at the northern end of the road where it meets West Shepard Avenue. Volunteers cut many of these trees in summer 2020.

There are some smaller specimens about six feet tall growing on the rocky face of the former quarry above the Teal Trail. I cut half a dozen of the ones that I could reach in May 2021. Others along the edge of the sharp drop off are too risky to cut. There are some scattered samples along the Teal Trail near Amrhyn Field that were removed in May 2021 and more will be removed in May 2022.

The namesake tree in Betty Smith’s 1943 novel, A Tree Grows in Brooklyn, is a tree of heaven.

This article gives the history of how tree of heaven was imported and became a problem, along with why it is difficult to kill: https://www.ecolandscaping.org/05/landscape-challenges/invasive-plants/tree-of-heaven-an-exotic-invasive-plant-fact-sheet/

Detailed information: https://extension.psu.edu/tree-of-heaven

Fact sheet: https://portal.ct.gov/-/media/CAES/DOCUMENTS/Publications/Pest_Alerts/10-30-18-Tree-of-Heaven-ID.pdf

Removing tree of heaven became a higher priority at West Rock when I first started seeing the destructive spotted lanternfly for the first time at the park in July 2024. More information on the spotted lanternfly is listed on this page: https://westrocktrails.blogspot.com/p/invasive-animals-attack-trees.html 

A tree of heaven growing along Baldwin Drive  in August, 202 1shows off its colorful seed pods.

This close view of the seed pods from a tree of heaven growing along Baldwin Drive in August, 2021 also provides a good look at the non-serrated leaves.

A number of partially cut tree of heaven trunks line an area near Baldwin Drive in Sept. 2020. The trunks were cut to the ground after this picture was taken.

Other Invasive Trees

Other potential invasive trees at West Rock, include the black locust and the Norway maple tree. I have not seen these, but they are likely at the park.

The black locust is native to other parts of the United States, but is considered invasive outside of those areas: https://www.invasive.org/weedcd/pdfs/wgw/blacklocust.pdf

The Norway maple, native to Europe and Western Asia, is commonly planted as a landscape tree: http://nyis.info/invasive_species/norway-maple/

I have thankfully not seen the Callery pear or Bradford pear tree at West Rock. There is a line of them along the sidewalk on Blake Street by the New England Montessori School. There are many reasons people should not plant these trees: they can easily spread into the woods; they are weak trees and often break during storms, and they keep their leaves a month longer into the fall, extending the leaf cleanup season. These trees have been banned in other states:

https://www.citizen-times.com/story/news/local/2021/03/23/curse-bradford-pear/6959233002/

Thankfully Connecticut finally banned this tree in 2024, but should not be waiting until 2027 to phase it out. A one-year time period to sell existing stock should be sufficient. Other plants banned by this new law, including wisteria vines, and other plants that are not likely to be planted in people's yards, including porcelainberry, mugwort, quack grass, and the Japanese angelica tree:

https://www.nbcconnecticut.com/news/local/invasive-plants-species-list-connecticut/3295380/

Invasive Reeds

Japanese Knotweed

This invasive is known as Godzilla weed in reference to its origins and the fact that it is impossible to kill. The stalks can grow to about 10 feet tall with heart shaped leaves mostly at the top. It looks like a short bamboo with distinctive rings every six inches. Unlike bamboo, the stalks are very fragile and are easily broken. It has an attractive white flower in late summer. The spring shoots can be eaten like asparagus. I have not tried this, so I have no comment on the flavor.

When uprooted, the plant will quickly resprout from the broken root pieces left behind in the soil. If cut, it will resprout from just below the point at which it was cut. The challenge in clearing this is getting back on a regular basis to keep cutting it until the roots die.
On a positive note, some say that it can be used to treat Lyme Disease. I have no personal experience with knotweed as a Lyme Disease remedy.

There is a patch of knotweed on Wintergreen Avenue, near the junction with Springside Avenue, across from the Brookside Apartments. This patch continues to spread north and south every year. There is a large patch on the Westville Feeder Trail by Amrhyn Field and the West River that I began targeting in 2020.

Japanese knotweed lines the forest edge along Wintergreen Avenue.

I have been fighting a patch of this on Baldwin Drive near the Orange Trail crossing. In summer 2014, I pulled it out three times, but each time the remaining patch was smaller. I returned from 2015 to 2021 to continue to pull out these plants. In 2017, I was pleased to see that native blackberry shrubs were growing and over time, I hope these will fill the area.

These two photos show a multi-phase project to remove Japanese knotweed along Baldwin Drive in summer 2014. The first photo shows all the plants I pulled in June 2014 and left along the road to dry. The second photo from July 2014 shows the dead plants from the first removal behind the plants that regrew, which I pulled out after taking the photo. I plan to continue to monitor this site to remove any other plants that regrow.

There is a large patch about 30 feet wide by 30 feet deep on Mountain Road, adjacent to a small parking lot near the Red Trail. From July to October 2016, it took me 14 hours worth of work over five visits to pull it and then pull it again when it resprouted. When I returned in November 2016, the patch was completely brown, but it resprouted in spring 2017. I returned with two helpers to dig it out by the roots. The patch resprouted again, but not as strongly, and I continue to fight the battle. I pulled as many as I could and cut the rest in Aug. 2017, and returned again in 2019, 2020 and 2021. The patch continues to grow back faster than I have time to return and battle it.
The technique I learned for this area is that knotweed has a root that is long in one direction (side to side), so if I pulled across the root, then I could fairly easily uproot it. When I dig it out, I use a pick mattock to pull out as much as I can.
In this area, I found a few raspberry plants, and grape vines that will hopefully spread with the knotweed removed from competition. Adjacent to the knotweed is some goldenrod and milkweed.
One concern is that the open field behind this knotweed patch is a vast sea of mugwort, which will seek to intrude into this area.

The weakness of knotweed is that its stem is fragile and easily cut. The challenge of knotweed, as compared to other invasives, is that it can regrow to full size within a growing season. By comparison, I can cut down a 15 foot tall autumn olive shrub with 3-inch diameter stems. When it reprouts, at the end of the season, the new shoots might be five feet tall with a quarter-inch diameter stems.
More information at https://nyis.info/invasive_species/japanese-knotweed/
This website chronicles a fight against Japanese knotweed in Massachusetts: http://www.ecolandscaping.org/09/invasive-plants/managing-japanese-knotweed-two-small-scale-strategies/#more-3756 

Japanese knotweed along Mountain Road in July 2016 before pulling.

The knotweed patch in July 2016 after two hours of pulling. Knotweed maze, anyone?

The Mountain Road knotweed patch in August 2016 after two visits.

I cleared the patch in August, and in September 2016, the patch aggressively resprouted, so I pulled it again.

The knotweed patch in September after it was pulled and partially resprouted and pulled again. A line of invasive mugwort can be seen at the back of this area.

In October 2016, the knotweed had resprouted, so I pulled it again.

The Mountain Road knotweed patch resprouted in May 2017.

The Mountain Road after being pulled and cut in May 2017. Near the street are daffodils planted by a neighbor. The patch continued to resprout through summer 2017 and was again cut back in subsequent summers (not pictured) as it continually resprouted.

Mugwort

Mugwort (artemisia vulgaris) is a reedy weed that grows about five feet high and will completely take over an area. It is readily pulled out and yields a distinctive spicy smell when pulled. It has uses in herbal medicine. I have found this on the Sanford Feeder Trail at the Regicides Trail where through repeated pulling, I have greatly reduced its number. It is also located on the Red Trail near the pond off Mountain Road, under the powerlines south of Mountain Road, and north of Lake Wintergreen.

More information: http://www.invasive.org/browse/subinfo.cfm?sub=5148

Herbal information page, for which I am not qualified to endorse the information should you wish to try it: http://www.botanical.com/botanical/mgmh/m/mugwor61.html

Mugwort lines the Red Trail under the powerlines, just south of Mountain Rd., Aug. 2017.

Mugwort displays a faint green flower. Native grapevines with their large leaves grow behind the mugwort along the Red Trail under the powerlines, Aug. 2017.

Phragmites or Common Reed

Phragmites australis is a tall reed about 8 feet in height common seen in Connecticut wetlands and marshes, and along lakes and ponds. The reed has a distinctive "flag" of seeds at the top. It displaces native cattails because it is taller and its roots spread aggressively.

Since they typically grow in soggy area, there is no easy mechanical way to remove them. Chemical control is the only viable solution, so I have not attempted to combat this invasive. There is phragmites along the dam at Lake Wintergreen, and in the marshy area north of the lake, both along the Red Trail. Regrettably, the plant is spreading north along the Red Trail.

More information at: https://nyis.info/invasive_species/common-reed/ and https://www.canr.msu.edu/news/invasive_phragmites_australis_what_is_it_and_why_is_it_a_problem

Phragmites grow along the Red-White Trail at the edge of Lake Wintergreen in 

November 2017.

Japanese Wineberry

Japanese wineberry is an invasive plant easily recognized by the short, bristly bright red hairs that line the round stems. These stems can reach 10 feet in length and arch back toward the ground where the tip will root when it touches the soil. Multiple stems grow from a center root. Wineberry forms dense thickets that displace native plants. The berries are edible by people and animals alike. Shallow-rooted wineberry is relatively easy to uproot either by hand or with a pick mattock.

Japanese wineberry blankets an area of woods near the climbing wall off the Teal Trail in March 2021.

Wineberry is easy to distinguish from these native plants:

Native blackberry has purple or green stems with angles that make the stem appear folded or grooved. Blackberry grows in a single cane from the root, is hairless and has sharp thorns.

Blackberry: https://plants.ces.ncsu.edu/plants/rubus-pensilvanicus/

Native blackberry grows near the sign for the Farm Brook flood control dam in January 2015.

Native blackberry blooms along West Shepard Ave. near Baldwin Drive in May 2018.

Native black raspberry has a circular purple stem with a white waxy coating and small, irregularly spaced purple thorns. Their stems can also be green.

https://www.tenthacrefarm.com/how-to-grow-black-raspberries/

Native red raspberry has green stems with sharp thorns.

Raspberry varieties: https://gardenerspath.com/plants/fruit/best-raspberry-varieties/

Hairy, invasive Japanese wineberry (left) grows alongside native black raspberry with its purple, waxy coated stems (right) along the Regicides Trail in April 2021.

Smaller Invasive Plants

Black Swallow wort

Invasive black swallow wort has been identified in two places at West Rock. There is a large section alongside the Regicides Trail over the West Rock Tunnel. There is another patch of it along the Regicides Trail, just north of the split with the Green Trail, shortly past Judges Cave. As this photo shows, it completely takes over an area.

More information on the plant is presented at this website: http://sewisc.org/invasives/invasive-plants/16-black-swallow-wort

This article "Invasive Vines Swallow Up New York's Natural Areas" calls this pale swallow wort, but the plant is the same: http://news.cornell.edu/stories/2014/04/invasive-vines-swallow-new-yorks-natural-areas

Invasive black swallow wort has completely taken over the slope
over the West Rock Tunnel alongside the Regicides Trail.

Garlic Mustard

Garlic mustard is a ground-dwelling plant that is green year-round and can quickly blanket an area. It has a vaguely heart-shaped leaf with notched edges. In the spring, it can growth to four feet tall and has a small white flower. One problem with garlic mustard is that it puts a chemical in the soil to inhibit the growth of other plants. It can be easily uprooted, but the challenge is pulling hundreds of them from a particular area.

You can eat this in salads. I have never tried. Feel free to pick as much as you like.
More information at https://kingcounty.gov/services/environment/animals-and-plants/noxious-weeds/weed-identification/garlic-mustard.aspx

Garlic mustard completely displaces other plants in the open field adjacent to the Hill Street parking lot, as seen in May 2015. The plant is easily uprooted and I pulled out some of these after taking this photo. They will grow again from all the seeds likely to be found in the soil.

Garlic mustard flowers in the field
adjacent to the Hill Street parking lot in May 2015.

Garlic mustard blankets the understory on an unblazed path from the Teal Trail to Springside Avenue, May 2021.

Japanese stilt grass

Japanese stilt grass is a grassy plant that with thin stems and leaves that are about a quarter of an inch wide. The plant blankets an area (think of a lawn) displacing anything native. The ones I have seen at West Rock are about a foot tall, but these websites report that it can grow as tall as three feet. This plant is easy to uproot, but because it can grow so widely, clearing a patch of the stilt grass is time consuming.

More info: https://extension.psu.edu/japanese-stiltgrass and https://nyis.info/invasive_species/japanese-stiltgrass/

Native, but Obnoxious: Greenbrier/Catbrier/Bullsbrier

This is a native species known by the scientific name of smilax bona-nox, but certainly NOT desirable along trails. I have gotten torn up by this plant that has distinctive green stem, with lethal sharp straight thorns that are yellow. It grows up into trees as high as 30 feet. I have seen this along various trails at West Rock. The name catbrier refers to thorns as sharp as cat claws,while bullsbrier most likely relates to its ability to act as a natural fence for cattle. I cut this back along trails where it threatens to scratch trail users, but leave it alone in the woods because it is native.
More info: https://www.wildflower.org/plants/result.php?id_plant=SMRO

Native, but Noxious: Poison Ivy, Poison Oak, Poison Sumac
The other obvious native candidates for native, but obnoxious are poison ivy, poison oak, and poison sumac (not to be confused with the native, non-offensive sumac tree). Unless you are pushing your way through a swamp, you are unlikely to encounter poison oak or poison sumac.

Poison ivy: https://www.wildflower.org/plants/result.php?id_plant=TORA2

Poison oak: https://www.wildflower.org/plants/result.php?id_plant=TOPU2

Poison sumac: https://www.wildflower.org/plants/result.php?id_plant=TOVE 

Poison ivy leaves grow in clusters of three where two of the leaves grow out to the side and the center leaf points forward. By comparison, the native, and non-offensive Virginia creeper has leaves that grow in clusters of five.

I cut poison ivy back only when it grows into trails. I certainly have reasons to dislike the plant, having gotten the weeping, itchy rash from trail work on a number of occasions.

Poison ivy berries are a food source for birds. The leaves turn a beautiful red in the fall. It is most easily recognized when it grows larger and the vines have hairy roots as it grows up the side of a tree. 

The clusters of three leaves of poison ivy can been seen on this tree along the Red-White Trail near Farm Brook Reservoir, in May 2015.

This tree along the Red-White Trail near Farm Brook Reservoir features both Virginia creeper with clusters of five leaves and poison ivy with its hairy roots and clusters of three leaves, in May 2015.

Invasive Flowers

Some beautiful flowers at West Rock unfortunately are invasive. While native wildflowers should NEVER be picked, the invasive ones should be removed. As with other invasive plants, please only uproot them if are absolutely sure of their identification, as some of these invasives resemble native flowers:

Sulfur Cinquefoil

This pale yellow flower is native to Europe and has a bitter taste that keeps native animals from eating it. Website: http://www.kingcounty.gov/environment/animalsAndPlants/noxious-weeds/weed-identification/sulfur-cinquefoil.aspx

Sulfur cinquefoil on the gravel road portion of the Red Trail
near Farm Brook Reservoir, Aug. 2015.

Crown vetch

Crown vetch is a legume with a flower that ranges in color from purple to pink to white. It grows in open fields and displaces native grasses and flowers. There are more aggressive invasive plants that demand a higher priority, so I leave this alone.  It is readily found at West Rock in the open field by the Hill Street parking lot, and near Farm Brook Reservoir. The state mows the field about once a year, so that helps control it. Information at http://sewisc.org/invasives/invasive-plants/169-crown-vetch and http://www.dcnr.state.pa.us/cs/groups/public/documents/document/dcnr_010284.pdf

Crown vetch grows in the field near the Hill Street parking lot, June 2015.

A close up of the crown vetch flower, June 2015.

Invasive Plants Benefits

This page would be incomplete without a discussion of the benefits of invasive plants, painful as this is to write. Certainly none of the benefits they offer outweigh their negative effects.

Probably their biggest benefit is that their roots retain soil, slowing erosion, particularly in steep areas. Since they often grow where native plants do not, they are a source of carbon storage on a planet where carbon dioxide levels continue to rise in the atmosphere. They do provide a food source for animals, even if those fruits are not the always best for them.

Some of the fruits can be eaten by people (wineberries and autumn olive berries), and other plants have edible parts as well (garlic mustard leaves and young knotweed shoots).

Some invasives are attractive in their own way: a blanket of green barberry bushes is prettier than brown earth, winged euonymus leaves are a beautiful red color in the fall, and honeysuckle flowers and bittersweet berries brighten up the forest.

Of course, the woods and its inhabitants would be better served if there were no invasive plants.

Non-Native, Non-Invasive Plants

Winged euonymus and privet are two excellent examples of non-native, highly invasive plants commonly sold for people to use in their yards. When planning for your own yard, please use native plants as much as possible. The local woods will appreciate your thoughtfulness.

There are various non-native plants used for landscaping that are NOT invasive, based on what I have seen. These plants are typically moderate in how fast they grow and if they produce seeds, they do not disperse into the woods. They may be seen in the woods in places where a house may have once been located, and subsequently removed and the property turned into open space. If you feel the need to plant non-native species, these appear to be less of a problem: English yew, Japanese forsythia, and Japanese andromeda.

Of these, I have only seen forsythia, which I would guess that someone planted. There are some forsythia shrubs along Regicide Drive near the South Overlook, and also one or two at the junction of Baldwin Drive and West Shepard Avenue. I have not cut these and have no plans to do so because they are not causing a problem, and my efforts are better focused on the invasives in this area that ARE a problem.

Any of the bulb flowers also appear to stay where they are planted including daffodils, lilies, and tulips.

A forsythia bush growing at the junction of Baldwin Drive and West Shepard Avenue blooms in April 2022.

Invasive-Free Areas

I would like to end this on a positive note by mentioning that there are many invasive-free or limited-invasive areas at West Rock, particularly the White Trail between Lake Wintergreen and its northern terminus at the Red Trail near Mountain Road. The Orange, Purple and Yellow Trails seem relatively uncontaminated, as are northern portions of the Blue Trail.

Invasive Plants Web Links

• The Plant Conservation Alliance's Alien Plant Working Group website is an excellent place to start learning about invasive plants. The alliance is a group of ten federal agencies working with about 290 other conservation groups on this issue. The website is subtitled Least Wanted: Alien Plant Invaders of Natural Areas identifies the problem plants through words and photos, and includes treatment options. The plant list is available in several forms, including a list by common name and scientific name: https://www.invasive.org/alien/factmain.htm
• Direct link to the page with the plant list: http://www.invasiveplantatlas.org/images.html

• The Farmington River Coordinating Committee of Massachusetts publishes A Landowner's Guide to Invasive Plant Management. Website: http://farmingtonriver.org/application/files/7314/7707/0765/Land_Owners_GuideLL71714.pdf

• The Invasive Plant Atlas of New England provide a variety of information, including a clickable list of plants and in which counties they are found, and also a list of plants with information and photos about them. You see the photos after you click on the link, so you need to know the common or scientific name of the plant to identify it. Main page: http://www.eddmaps.org/ipane/
• 
  
• The Connecticut Invasive Plant Working Group, a consortium of agencies dealing with the issue, has information about invasive plants.
• Main website: https://cipwg.uconn.edu
• Invasive plant list: https://cipwg.uconn.edu/invasive_plant_list

• The Connecticut Department of Energy and Environmental Protection (DEEP) Invasive Species page has links and other information about invasive species, both plants and animals:
• http://www.ct.gov/deep/cwp/view.asp?a=2702&q=323494&depNav_GID=1641

• The U.S. Forest Service publishes a field guide to the invasives discussed on this page, plus a few others with pictures and information. The guide is called Invasive Plants Field and Reference Guide: An Ecological Perspective of Plant Invaders of Forests and Woodlands. If you want to get a quick overview of the common invasives in a pocket guide, this is a good place to start: 
• https://www.fs.usda.gov/treesearch/pubs/20715

• The U.S. Department of the Interior has a National Invasive Species Council, which oversees federal activities in this area. Website: http://www.doi.gov/invasivespecies/index.cfm

• The U.S. Department of Agriculture maintains a website called National Invasive Species Information Center: Gateway to invasive species information; covering federal, state, local, and international sources at http://www.invasivespeciesinfo.gov/index.shtml. The direct link to the information page, which has a list of links to other publications and websites, is here: http://www.invasivespeciesinfo.gov/resources/identify.shtml.

• If you want to distinguish an invasive species from a native species, use the guide Mistaken Identity: Invasive Plants and their Native Look-Alikes: An Identification Guide for the Mid-Atlantic, published by the Delaware Department of Agriculture, and found at this website: http://www.nybg.org/files/scientists/rnaczi/Mistaken_Identity_Final.pdf

• If you have some time to search, the University of Wisconsin-Madison has an interactive Weed Identification and Management Guide. The website guides users through a series of steps and questions to identify a weed unknown to the person: http://weedid.wisc.edu/weedid.php

• The Southeastern Wisconsin Invasive Species Consortium has a comprehensive list of invasive plant species on its website at http://sewisc.org/invasives/invasive-species-gallery.

• The New York Invasive Species Clearinghouse has excellent resources about all types of invasive species, both animal and plant, and aquatic and terrestrial at https://nyis.info

This poster was developed by the New York Invasive Species Clearinghouse.