GoGardenNews - Items of gardening and ecological interest — invasive species

John Pitarresi in a "Special to the Observer-Dispatch" declared that "Japanese knotweed is a menace.Even more than we knew. Knotweed is that tall, big-leafed plant that grows most commonly along creeks and rivers in dense stands that can be almost impossible to walk through. Some call it bamboo, which it superficially resembles. It makes recreation in some areas very difficult, and it displaces native plants in a big way. And more than that.

Photo by Karan Rawlins; University of Georgia

If there's not enough for you to fear, we're being warned about Cogon Grass (Imperata cylindrica). It's native to Southeast Asia and possibly to East Africa. It was introduced to the U.S. by accident, then intentionally. It's a beast.

Invasive exotic species are considered one of the main causes of the current biodiversity crisis. In recent years, humans have introduced 200 species of ant from outside of their natural area of distribution and some of them have become invasive. Such is the case of the Asian needle ant, Brachyponera chinensis, which has seen its area of distribution greatly expand in the last 80 years.

State forestry officials are warning people to be on the lookout for “one of the 10 worst weeds in the world” as spring blooms across Georgia.

Heavenly Bamboo - aka Nandina - was once considered to be a stellar selection for landscapes. Evergreen foliage, long-lasting red berries and exotic appearance made it very popular.

However, it has made its way uninvited into woodlands, displacing native plants, and the berries can poison birds.