So many plants that were difficult to obtain years ago are now much more available online. The internet does more than give everyone access to nurseries and seed suppliers that sell online. It also makes it possible to communicate with others who might want to share plants and seeds from their own gardens. The advantages are obvious, but there are innate problems with so many plants being too available.
Before humans started to relocate plants all over the world, plants were much more confined to certain regions. Once relocated to new regions, some plants naturalized and became problematic for the plants that were already there. Exotic (non-native) plants often had the advantage because pests that troubled them back home had not come with them.
For example, pampas grass had been confined to the Pampas region of South America. It was imported to California and Oregon because its fluffy flowers and graceful texture are so appealing. The problem now is that it naturalized, and continues to proliferate and crowd out native plants in coastal ecosystems, without natural pathogens to slow it down. The availability of so many more plants from so many more regions seriously increases the potential for the importation of invasive exotic plants, as well as plant diseases and even insects!
Another potential problem is that common names of plants can be very different in different regions. Now, this can be an advantage when seeds from a common yucca in Lubbock, Texas might actually be from the very uncommon plains yucca (Yucca campestris, which I recently purchases on Ebay!). The problem is that the yucca known as ‘Adam’s needle’ in Georgia may be a completely different species from what is known as such in Pennsylvania, Oklahoma or anywhere else. A plant described as a ‘mimosa’ could be a silk tree, a jacaranda tree, or any of several different acacia trees!
It is known by a few different common names, including ‘Andean pampas grass’, ‘purple pampas grass’, and simply ‘pampas grass’. ‘Andean pampas grass’ sounds almost like an oxymoron, since the Andes Mountains are in a separate region to the west of the pampas region of Uruguay and eastern Argentina. ‘Purple pampas grass’ is even sillier, since it is devoid of any purple.
This is a relatively new development. The first few arrived here only two years ago. By last year, a few more arrived to make a significant herd that split into two smaller herds. Now these two smaller herds are quite significant. If they continue to proliferate as they have been, they will become more of a problem. They are already shredding flowers and colorful berries that are within their reach, and digging up flexible irrigation hoses.
Just about everything in this picture is icky! This species of pampas grass, Cortaderia jubata, is one of the most aggressive and noxious of the invasive exotic specie that have naturalized here. It seems to be incarcerated behind the weathered cyclone fence with barbed wire on top. The big water tank is is a harshly stark background. The tired old Douglas firs and ponderosa pines to the left and right seem to be unhappy here. The small coast live oak that is at least trying to make a more cheerful appearance is only oppressed by the surroundings. Only the clear blue sky above lacks the ick factor.
It is pretty but pervasive. Actually, I do not really find scarlet pimpernel to be all that appealing, but this is how someone who reads my gardening column in the Santa Ynes Valley News describes it. Embarrassingly, she requested that I discuss scarlet pimpernel while it was more of a problem back on June 7, but I only recently read the message. By now, it is already dying back for autumn, and is completely deteriorated in dry and hot exposed areas. It will be back next spring, and will bloom with tiny peachy orange flowers so that it can throw tiny but ridiculously abundant seed by summer before anyone notices. Flowers can be other colors in other regions. The sprawling stems can spread more than a foot wide, and can get up to about ten inches high if sprawling over other weeds. The tiny and soft leaves are arranged in opposing pairs. Scarlet pimpernel may not seem like much of a threat now that it is deteriorating, but new seedlings will be profuse early next spring, and can compete with seedlings of more desirable plants.
Nature has been getting by just fine for a very long time before humans started to interfere. It has survived all sorts of catastrophes literally longer than anyone can remember. It was here when dinosaurs were exterminated by a meteorite or comet or vulcanism or whatever catastrophic yet natural event finished them off. In fact, Nature was here for all of the few mass extinction events of the very distant past, including the Permian – Triassic Extinction, which only about 4% of life on earth survived! We all know that “It’s not nice to fool with Mother Nature.”, or serve her margarine that tastes like real butter; but we should also realize that it is rather presumptuous to think that we can be more efficient with correcting all environmental damage. Very often, it is best to let nature do what nature does best.
Every invasive exotic (non-native) species has a story of how it got here.
Tony Tomeo 