Invasive plants easily adapt to changes in the environment, including those factors influenced by changing weather and climate patterns.
In fact, non-native invasive plants can more rapidly respond to both a rapid fluctuation in the weather as well as to long-term shifts in climate patterns. For example, non-native honeysuckle bushes will be the first plants to leaf out in early spring.
Local residents may be complaining about the cold this week, but just a few warm days in early March are enough to trigger the growth response of honeysuckle…and buckthorn too. When these non-native shrubs leaf out early, they can prevent smaller native plants from developing and can even influence birds to begin building nests when it is too early in the season. In addition, many invasive plants set seed in a variety of weather conditions, have a longer growing season, and can survive in a wider range of temperatures.
More consecutive years with early spring weather patterns and slightly warmer growing seasons often ends up favoring invasive plants’ growth and survival over native plants that are adapted to remaining dormant through traditionally longer winter seasons.
Shifting climate patterns that include even slight increases to average yearly temperatures and changing precipitation patterns will also increase the challenges of controlling new invasive plants. Even now, problem plants that were previously thought not to survive in northern climates (such as kudzu vine, which literally grows in feet per hour) are expanding their distribution into Pennsylvania. Native plant communities cannot always compete with these “super plants” as they invade new areas.
While people cannot control the local weather, and shifting climate patterns seem inevitable for the near future, keeping a wide diversity of native plants in natural areas, trees, shrubs, flowering plants, and grasses, will strengthen the ecosystem against possible threats that include invasive species. Though not all native plants may fair as well through very long-term shifts in the environment, at least some of them will. This is yet another reason why promoting native plant diversity is important in the fight against invasive plants or insects.
(Kimberly Bohn is with Penn State Extension and Jody Groshek is with McKean County Conservation District.)
(Editor’s note: This is the fourth in a week-long series to mark National Invasive Species Awareness Week with the McKean County Conservation District.)