Are you harboring an Alien?

Aliens come in all shapes & sizes. They can be ugly, pretty, destructive, enjoyable & a nuisance. Now, I am not talking about those green faced, large eyed Martians from the movies. I am talking about something more sinister, creeping into your backyard during daylight hours, floating on a warm summer breeze, hitching a ride among unsuspecting travelers. They are Invasive plants & they are in your neighborhood right now!

One of the largest invaders into our yards is the Norway Maple. This large tree is similar to our own native Sugar Maple, but is actually a European invader. First introduced to the US in 1756, this tree can grow upwards of 100 feet tall. The gray bark has regular shallow grooves, almost like netting. The Norway Maple generally has green leaves that turn yellow in the fall although there is a variety that has dark red leaves. This tree has historically been a favorite for parks, yards & cities. The biggest problem that this tree creates is aggressive growth resulting in native trees & plants being out competed for nutrients & sunlight. This eventually leads to decreased plant diversity & a change in the native forest habitat. There are solutions. Obviously removing the tree is the first option that comes to mind, however in many situations that is not practical. If a tree cannot be removed or a home owner would prefer to keep the tree then regular checks & removal of seedlings by hand or saw is recommended.

Alien #2 is the dreaded Burning Bush. This ornamental shrub is a popular invader. It is easy to grow, likes full sun to shade as well as any type of soil. But it’s the fall colors that attract us like bees to honey. In the fall this Asian invaders’ leaves turn a crimson red, but don’t let that beautiful color fool you. This shrub can live almost anywhere, crowding out native species & dispersing far distances by birds that eat the fruit & deposit the seeds.

Another bad alien is the Barberry. This plant  is commonly dispersed by birds. Introduced to the US in the 1700’s from Europe, the Barberry was grown for hedges, jam made from the fruit & a yellow dye from the plant. In addition this plant has nasty long spines just waiting to grab you! Ouch! Banned from sale in many states, Barberry can still be found in Maine.

Both the Burning Bush & Barberry can be controlled by hand pulling. Herbicides can be used on all three of these invaders but must be applied properly by a licensed applicator.

Although none of these aliens will steal your first born, or perform experiments on you (at least I don’t think so…) they are ones to watch out for. Many terrestrial invaders can still be found for sale in Maine since these plants still bring in a profit. Many nurseries are aware of these invaders & can suggest other alternatives.

There are several common ways that these invasives arrive in our backyards such as dispersal by the wind or birds, and planting by unsuspecting homeowners. But the most common way is through the construction of new homes and roads when large amounts of gravel & soil are trucked in. Tiny seeds & plant fragments are often hidden in the soil. Once delivered to a new site & spread the seeds begin to grow into plants that will out compete native species.

There are many more terrestrial & aquatic invaders threatening our New England landscape. Our website has a list of these invaders & many links to management information at www.yorkswcd.org.

Happy Gardening!