We see them in the news from time to time: a dreaded new weed or bug or disease or something that is causing problems. You may have recently heard of Japanese climbing fern, zebra mussels, and raspberry crazy ants.
Years ago, we would talk about fire ants, kudzu, or privet. But what about plants such as Bermuda grass or Bahiagrass? Most folks wouldn’t think of them as such. Yet many homeowners and gardeners would call these non-native grasses invasive.
According to the Federal Registry, Executive Order 13112 defines invasive species as
“a species that is non-native (or alien) to the ecosystem under consideration and whose introduction causes or is likely to cause economic or environmental harm or harm to human health.”
An invasive species grows/reproduces and spreads rapidly, establishes over large areas, and persists. Species that become invasive succeed due to favorable environmental conditions and lack of natural predators, competitors and diseases that normally regulate their populations.
This includes a wide variety of plants, insects and animals from exotic places. As invasive species spread and take over ecosystems, they decrease biodiversity by threatening the survival of native plants and animals. In fact, invasive species are a significant threat to almost half of the native U.S. species currently listed as federally endangered.
In addition to negatively impacting ecosystems, invasive species are also costly. It is very expensive to prevent, monitor and control the spread of invasives, not to mention the damage to crops, fisheries, forests, and other resources. Invasives cost the U. S. $137 billion annually. Some of the most harmful species cost in excess of $100 million annually. An acquaintance of mine once said these invasives were “evasive” as they were so difficult to control.
Sometimes you will see invasive species referred to as exotic, alien, or non-indigenous species. The problem with these names is that they only refer to the non-native part of the definition above.
However, most exotic species do not cause harm to our economy, our environment, or our health. In fact, the vast majority of “introduced” species do not survive and only about 15% of those that do go on to become “invasive” or harmful.
Truthfully, many wonderful exotics have become a beloved part of our diet. Imagine an east Texas garden without peas, onions or cucumbers that originated from the mid-East. Or pears, turnips, and a fig tree from Europe and the Mediterranean. Watermelons came originally from the African continent.
Understanding invasives and the threats they currently pose us is important.
This Monday, March 20 at 6:30 pm the Angelina County Extension office will hold its monthly educational seminar on the topic of Understanding and Dealing with Invasives. Guest speaker Mike Murphrey, with the Texas A&M Forest Service, will discuss forest health and the identification and prevention of invasive species.
Cost is $10 per person, 1 CEU will be given to pesticide licensees. For more information call 936.634.6414.
