Wednesday, June 23, 2010

Sericea Lespedeza- Fugitive From Justice

Sericea lespedeza is not on the "Eleven Most Unwanted" list in Missouri, otherwise known as the Noxious Weeds of Missouri.  One of the most invasive species, its absence is due to politics that I won't go into.  However, its failure to pass the legislative test doesn't mean it should be ignored.  It is a major invader of agricultural fields, prairies and even glades such as Rocky Barrens where it has become a major problem.
As described in MDC Online, it was first introduced to the US in 1896.  It was planted in pastures because although it was exotic, it was easy to plant and would grow virtually anywhere (a big red flag for invasive characteristics.)  Two varieties of sericea were developed for improved forage quality and nematode resistance. These varieties were used on highway rights-of-way, dams, and waterways. In the 1930s it was planted on strip-mined land in southeast Kansas and Missouri.  It was used extensively by MODOT and other states transportation departments for stabilizing soil although its root system is a long tap root.

It is avoided by grazing animals, with the exception of the famously omnivorous goats.  Sericea has large amounts of tannins which taste bad to animals (and insects) and interfere with digestion by binding proteins.  If cut for hay, after several weeks the tannins break down and they can be used for feed.
Like many invasive species, its tall prolific branching shades out natural species.  Being very shade tolerant, it can easily invade forested land.  Its lack of palatability means that surrounding plants are more likely to be grazed down, giving it a head start.  It also produces allelopathic chemicals which are released from the roots and leaves.  These chemicals inhibit seed germination and growth of grasses.
Identification information is available at this MSU Website.

If any of you Master Naturalists would like some hands-on experience, call Kevin Hedgpeth with the Missouri Department of Conservation.  He is tasked with spraying Sericea lespedeza at Rocky Barrens and another site and could use the help.  You can reach him at 417-751-3856 or Kevin.Hedgepeth@mdc.mo.gov