In our pond business we sold lots of plants. Many companies now days become pond installers because they were landscapers and in general do not have much information about aquatic plants. In turn the pond installers often end up selling plants to the pond owner.
With little knowledge, plants that are pretty or distinctive are sold and many of these are invasive to certain parts of the country.
In our area the common pond plants are water hyacinth, Anachris, horse’s tail, yellow flag iris, cattail, parrot feather, and various water lilies and lotus.
Of these plants, of which there are eight, six of them are invasive species. I could break down the water lilies and lotus, but the point is that we all need to learn more about invasive species and what their threat is.
I like to fly fish and was alarmed when I was out in Idaho and discovered that Henry’s Fork has loads of Anachris canadensis.
It appeared to me that it was identical to what we have been selling to pond and water garden enthusiast for years.
Anachris is also know as Egeria densa and is also called Brazilian Elodea. With all these separate names it becomes confusing to know what a plant should be called. There are a couple of links that I want to mention. One is by Florida Aquatic Nursery and give this issue a little of the commercial flavor. The most comprehensive site that I found that explained all the details of this plant is xxxxx.
From my observations of this plant it overwinters well here and seems to like the shaded slightly cooler water of mid summer. If it gets to hot as created by being in shallow water a great deal of it will turn to mush. If it gets into our waterways and lakes, Anachris can become a serious problem. The linked referenced above is the site for Florida Aquatic Nurseries and is worth reading. Another very good site which explains how to differentiate between the various species is www.wetwebmedia.com/PlantedTksSubWebIndex/elodea.htm written by Bob Fenner.
As time allows I will add more information about other invasive aquatics.