In the history of land management, there have been countless species that have been planted that later became invasive. Perhaps the worst example of this is sericea lespedeza, which will quickly take over open areas if allowed. Now is the time of year to stop it!
Plant Characteristics
Sericea lespedeza is a perennial legume that was introduced to the U.S. from Asia. It has a trifoliate leaf (3 leaflets), and typically grows to about 4 feet tall. It was originally planted for livestock forage and erosion control, and some advocated that it was a good wildlife plant because of the abundance of seed it produces. However, it is a noxious weed that is extremely poor deer forage, and the seeds provide no nutritional value to quail. To make matters worse, the seed can survive in the seedbank for decades.
Control Options
(Above) Sericea was killed with a broadcast application of glyphosate. Due to the thick stand, some plants were not killed, and spot treatment will be necessary. This highlights the need to visit stands after treatment to ensure all plants were killed.
Given the low wildlife value of this invasive plant, managers should work hard to fight it. Practices such as mowing or burning do not kill sericea, although they are useful to set it back prior to herbicide treatments. Additionally, these practices work well to prevent plants from going to seed if you will be unable to spray them this year for some reason. Burning is particularly useful, as it also helps sericea seeds germinate and will aid efforts to exhaust all of the dormant sericea seed that is already in an area.
There are several herbicide options that work well for sericea. Round Up (glyphosate), PastureGard (triclopyr and fluroxypyr), and Garlon (triclopyr) all work well to kill sericea. Be sure to follow label recommendations, and apply treatments in the most efficient manner possible. Spot-spraying can work extremely well, but in areas with high coverage, broadcast applications are appropriate. The most important thing is to kill all of the sericea, as native plants will fill in quickly, even if you kill all those already growing in a spot.
In It For The Long Haul
Unfortunately, sericea lespedeza is a plant that most managers will fight for the rest of their lives, the long-lived seeds and aggressive nature of the plant ensure that. But with a little work every year you can reduce coverage of this weed and open up spaces for native plants to grow.
