Lois Stack Ornamental Horticulture Specialist
I’m Lois Stack with the University of Maine Cooperative Extension in Orono, Maine. I work
with Maine’s landscape nursery greenhouse industry and also with home gardeners, and
increasingly over the last few years, one topic has dominated my conversations –
invasive plants. Invasive plants aren’t just weeds – weeds are plants that get out
of place. An invasive plant has a number of characteristics.
Invasive plants are not a new issue in Maine, but they’ve become more important in the
last few years for two reasons. First of all, we have a lot more commerce and a lot more
plants coming into Maine. And secondly, we have global climate change, which is allowing
plants that didn’t used to survive in Maine to survive our winters.
Invasive plants cause a lot of problems. In our natural areas they out-compete plants
and animals, change the diet of our animals and cause serious problems with our native
communities. In recreation areas they can clog waterways and cause economic problems
to Maine’s tourist industry. In our own backyards they cause a lot of anxiety and
grief, and can cause our property values to go down.
So what can you do about invasive plants? There are five good plans of action. First,
don’t buy invasive plants. If you go to a place that’s selling a plant like this
one – this is Norway maple, which is a common street tree and becoming invasive in Maine
– ask the question. Find out if it’s invasive and then find an alternative plant.
Number two: Replace the invasives that are in your yard. This plant I’m standing in
front of is one of the invasive honeysuckles--Morrow’s honeysuckle. Rather than leaving a plant like
this that out-competes a lot of other shrubs and understory in your yard. You could replace
it with another wildlife shrub. Number three: Volunteer for a community cleanup
project. Those invasive plants out there are not going to go away without our help.
Number four: Educate your neighbors. Many invasive plant problems move from one yard
to another. For example, this plant is a vine – this is Asiatic bittersweet – that
climbs and actually throttles large trees, and the seeds are moved around by birds. So
if your neighbors have it, you may have it in a few years thanks to those birds.
And number five: Talk to park managers, town managers and town officials to find out if
there’s some project that you might start or if you can influence the plantings in your
town.