Sustaining the Good Life
The Necessary Battle against Invasives
In a previous newsletter we focused on the very real threats to the forest products industry (fuel, lumbering, and maple sugar production, etc.) from invasive insects - specifically the Emerald Ash Borer, Asian Longhorn Beetle, and the Wooly Adelgid - and why people should not bring firewood from more than 50 miles away or from other states into Vermont. Here we focus on invasive plants and why people need to control them.
One look at omnipresent Japanese knotweed flowering whitely beside roads and rivers makes it clear that Vermont has a serious problem with those unwanted aliens. And if you think that insects are the only threat to treasured sugar maples, think again. Norway maple are hardier, more salt tolerant, more prolific, and their seeds less desirable to wildlife. They are not as valuable for production of what might be called the "elixir of the gods" for which Vermont is so famous, their colors are not as beautiful, and their form is uglier, with an often distinctive thick lower limb that throws off the tree's symmetry. Moreover they are crowding sugar maples out.
Vermont, already coping with Buckthorn, various honeysuckles (for example: bush and vine), and other invasive plants, is just a few years behind the next alien explosion by Japanese barberry, burning bush (winged euonymus), and, yes, Norway maple. Those plants are here, and one year their numbers will explode. We need to stop them now.
Several factors distinguish non-native invasive plants and make them a threat to the native species we value and upon which wildlife depends for sustenance and overwintering habitats. The exotic species are incredibly hardy, exceedingly adaptable (to soils, light, water, salt, etc.), and prolific; have no natural enemies, no checks and balances, so vigorously displace more desirable plantings; frequently create a monoculture and exude a chemical into the soil that deters other plants; and can fool wildlife into laying eggs on the similar plant, often with deadly consequences. The classic example of that last situation is of the Monarch Butterfly, which depends upon the milkweed plant for nourishment to young. When invasive black swallow-wort is present, the female often lays her eggs on that plant by mistake (even though the invasive's pod is much smaller and narrower than the milkweed's), and when the young hatch, the caterpillars die because they do not have the proper nourishment.
To learn more about invasive plants in Vermont, go to http://vtinvasiveplants.org or www.nature.org/vermont. You can find information there on identification and control that will enable you to control these plants on your own property and motivate you to support local efforts to control these invaders on public lands.
The Vermont Invasive Exotic Species Committee and The Nature Conservancy [TNC] are collecting data to make the case that Japanese Barberry, burning bush, and Norway maple should be added to the quarantine list that prevents their sale in the state. They are looking for documentation of wild places (hedgerows, forests, fields, river banks, wetlands, etc.) on either public or private lands where these plants have naturalized. They are urging scores of citizens to complete a report form and submit it before the end of October. The form is on both websites and is another way individuals can help protect biological diversity.
Meanwhile, if you learn of a plant that has berries enjoyed widely by birds, reproduces quickly, grows in almost any condition, and has no enemies, chances are you are looking at a present or future invasive. Anyone interested in participating in a workday that will include some invasive removal, along with other trail maintenance, is invited to join Museum habitat efforts at the Village Park and other locations. Check the program listings to see if one will fit your schedule.
