||By Lyn Chimera|
Invasive plants are like super weeds. They aren’t native to our area yet have such strong growth and reproductive capabilities and little to no predators that they can displace native species and invade your gardens as well! Worldwide invasive species are considered to be the second leading cause of species endangerment and extinction. Habitat loss and fragmentation is the primary source.
So how did they get here? People have been moving plants since the beginning of plant cultivation. Many plants were brought over by European settlers to be used as food, medicine, or for garden beauty. Non-native ornamental plants first appeared in plant catalogues in the mid 19th century. Some alien plants arrive by sneaking in within shipments of other items. Seeds or plants could inadvertently be included in a shipment of other plants, ballast (for aquatic plants), or the soil left on crates, etc.
Not all introduced plants become problematic. A small percentage of introduced plants are responsible for the majority of invasive plant problems. About 675 out of nearly 5,000 introduced plant species now growing on their own in woods, fields, marshes and other “wild” habitats are considered problematic.
Our Natives have evolved along with animals, birds, and insects to create a natural “balance of nature”. In some cases, there’s no animals or insects that eats an exotic plant because they don’t recognize it as food! Left unchecked some of these alien species reproduce faster than the native plants. This takes over the habitat of the natives which in turn diminishes the food and habitat for local animals, birds and insects that was part of that natural balance.
Two Invasives to watch out for:
Lesser Celandine (Ficaria verna), is a spring ephemeral (dies back after flowering like a tulip). Therein lies the problem. It’s a pretty little ground cover so people tend to ignore it after it dies out. Native to Europe and Asia it was most, likely introduced in the mid 1800’s as an ornamental. Two major problems, it doubles itself each year and is difficult to eradicate. It’s crucial that you remove it when you see it. The reason it’s hard to get rid of is there are little “bulbetts” at the end of each root. When you dig up the plant you need to take the soil mass with it so no bulbetts are left behind. If you have large masses of it use the smothering technique with black plastic, newspaper or cardboard layers covered with topsoil or mulch. You can get information at: https://blogs.cornell.edu/weedid/2021/04/19/spring-garden-thug-lesser-celandine/
Barberry, (Berberis thunbergii ) is one of the most common surubs in home landscapes. It comes in a variety of leaf colors and is easy to maintain. One of its most desired features is nothing eats it. That’s where the problem starts. Birds eat the seeds and drop them in forests and open areas. Since barberry has no enemies, it is fast overtaking the natural habitat in our woods and crowding out native shrubs and the food and habitat they provide. It was imported from China and Japan in the 1860’s and has now spread in the wild in 31 states and 4 Canadian provinces.
Not only is barberry invading our woods there is a high correlation between the number of black legged ticks and barberry. Barberry have thin but sharp thorns and provide a safe habitat for mice which safely hide under the shrubs. The ticks live on the mice which are a main way lime disease is transmitted. In woods where invasive barberry has been removed have a drastic reduction in ticks.
It has been illegal to sell barberry in NYS for a few years however many people still have them in their landscape. If you do, consider replacing them with something that’s not invasive.