ShareThis Page
Regional

Invasive plants: Southwestern Pennsylvania's most wanted list

Patrick Varine
| Friday, June 15, 2018, 9:15 p.m.
Multiflora rose is an invasive shrub.
Richard Gardner, UMES, Bugwood.org
Multiflora rose is an invasive shrub.
Mile-a-minute is an invasive vine.
Leslie J. Mehrhoff, University of Connecticut, Bugwood.org
Mile-a-minute is an invasive vine.
Garlic mustard is an invasive herb, but is easy to remove.
Rob Routledge, Sault College, Bugwood.org
Garlic mustard is an invasive herb, but is easy to remove.
Tree-of-Heaven is an invasive tree species.
Annemarie Smith, ODNR Division of Forestry, Bugwood.org
Tree-of-Heaven is an invasive tree species.

Invasive plants are not native to an area, can spread quickly and even cause economic or environmental harm — sometimes even threaten human health, the Pennsylvania Department of Conservation and Natural Resources reports.

Sometimes called as "exotic," "alien," "introduced," or "non-native" species, invasive plant infestations nationwide impact more than 100 million acres — or about the size of California, The Nature Conservancy reported.

The list of invasive plants in Pennsylvania includes 14 trees, 14 shrubs, 12 vines, 13 grasses, 27 herbs and 11 aquatic plants.

Local, regional and statewide groups that deal with invasive plants point to several varieties as being among the most pervasive in Southwestern Pennsylvania:

Multiflora rose

Introduced as ornamental rootstock from Japan in 1866, the Soil Conservation Service promoted its use in the 1930s for erosion control and livestock fencing. Recognition of its nearly unstoppable growth came too late, and it is now considered a noxious weed in many states.


Tree-of-heaven

Brought to Philadelphia in 1784 from China by an amateur gardener, this plant was the subject of Betty Smith's well-known book "A Tree Grows in Brooklyn." In addition to being invasive, tree-of-heaven stands are connected by underground roots, which produce a chemical preventing the establishment of other plant species nearby. It is often confused with native sumac, however tree-of-heaven leaves have a small gland on their underside.


Garlic mustard

First recorded in Long Island, N.Y., in 1868, garlic mustard is a cool-season biennial herb with triangular or heart-shaped leaves, which give off an odor of garlic. It is native to Europe but now ranges from eastern Canada south to Georgia and west to Oregon.


Mile-a-Minute

Growing up to 6 inches per day, mile-a-minute is a flowering vine first introduced to Eastern Pennsylvania in contaminated nursery stock from its native Philippines. It is covered with small, curved spines and produces green fruits that turn a metallic blue as the season goes on.


Source: Pennsylvania Department of Conservation and Natural Resources

TribLIVE commenting policy

You are solely responsible for your comments and by using TribLive.com you agree to our Terms of Service.

We moderate comments. Our goal is to provide substantive commentary for a general readership. By screening submissions, we provide a space where readers can share intelligent and informed commentary that enhances the quality of our news and information.

While most comments will be posted if they are on-topic and not abusive, moderating decisions are subjective. We will make them as carefully and consistently as we can. Because of the volume of reader comments, we cannot review individual moderation decisions with readers.

We value thoughtful comments representing a range of views that make their point quickly and politely. We make an effort to protect discussions from repeated comments either by the same reader or different readers

We follow the same standards for taste as the daily newspaper. A few things we won't tolerate: personal attacks, obscenity, vulgarity, profanity (including expletives and letters followed by dashes), commercial promotion, impersonations, incoherence, proselytizing and SHOUTING. Don't include URLs to Web sites.

We do not edit comments. They are either approved or deleted. We reserve the right to edit a comment that is quoted or excerpted in an article. In this case, we may fix spelling and punctuation.

We welcome strong opinions and criticism of our work, but we don't want comments to become bogged down with discussions of our policies and we will moderate accordingly.

We appreciate it when readers and people quoted in articles or blog posts point out errors of fact or emphasis and will investigate all assertions. But these suggestions should be sent via e-mail. To avoid distracting other readers, we won't publish comments that suggest a correction. Instead, corrections will be made in a blog post or in an article.

click me