Invasive species (I): Agave americana

With this post we want to start a series of these dedicated to invasive species, given their relevance, as we have already explained in our article Invasive species, environment and economy, and as the EU has recently demonstrated through the Regulation 1143/2014 of October 22.

On this occasion, we are talking about a case in which we were struck by the presence on the slope of the Jucar Canyon of a species with a robust appearance, with large basal rosettes of fleshy leaves, reminiscent of the well-known plant of Aloe vera. We bumped into her on a visit to the El Molinar Reservoir, in the town of Villar de Ves (Albacete).

It's about the species Agave americana, commonly called common pitera or magüey. It is a plant native to eastern Mexico, considered an invasive alien species in our country, as can be found in the Spanish Catalogue of Invasive Exotic Species and in the Atlas of Invasive Alichthonous Plants in Spain.

This plant was introduced to Europe in the 16th century, through Spain by the conquerors of the New World, first as an ornamental plant and then as a textile plant for obtaining coarse-grained fibers. In the south-east of the Iberian Peninsula, it has traditionally been used to mark roads, delimit farms, produce fodder and even as a construction material in traditional rural architecture.

As is the case with a large majority of species considered invasive in our country, this plant can actively reproduce asexually starting from rhizome, from which abundant rosettes sprout and can expand at great distances from the mother plant, making it a very prolific species, as well as being very resistant to drought and high temperatures.

Its eradication is very laborious and difficult, since for it to be effective it is necessary to remove all its rhizomes and repeat the operation for several years, until it is verified that there are no new shoots.

One of the main problems posed by invasive species is the effect of displacement of native species due to space competition and alteration of the environment.

Recently, the brochure was published Invasive alien species, the EU's answer, which provides detailed information on the problems, management, actions and definition of these species, among other issues.