Controlling sericea lespedeza
By David G. Hallauer
Meadowlark District Extension Agent, Crops and Soils/Horticulture
Sericea lespedeza is a serious problem in many of our grasslands--and should be easily spotted at this time of year. And that means time to look at control to reduce the massive seed bank that helps reestablish stands.
The control product of choice varies by time of year and stage of the plant. Remedy and PastureGard work well in June, and maybe early July, at which time hot weather and advancing maturity will reduce control until the plants start to bloom.
Bloom starts in August and September. That's when products containing metsulfuron, such as Escort XP, Cimarron Plus, and Chaparral are generally more effective. Recommended rates are 0.5 ounces per acre of Escort XP, 0.625 ounces per acre of Cimarron Plus, and 2.5-3 ounces per acre Chaparral. For spot application, mix 1 fluid ounce PastureGard per gallon of water, use a one-percent solution of Remedy Ultra in water, 0.3 grams Escort XP per gallon of water, or 0.7 grams Chaparral per gallon of water. Addition of a dye will help you see what plants have already been treated.
Aerial applications of these products should be done with a minimum spray volume of three gallons per acre. Higher spray volumes (e.g. five gallons per acre) will generally be more effective. Areas that contain sericea lespedeza and have been hayed can be sprayed with herbicides about four to six weeks after harvest.
Herbicide treatments will need to be repeated every two to four years to keep this invasive species in check. Initial treatments should reduce dense stands to the point where spot treatment can be used in future years. Left untreated, sericea lespedeza will dominate a site, greatly reducing forage production and species diversity.
If you're seeing a general turf browning in your fescue lawn, it could be brown patch. The warm night temperatures (upper 60s and higher) and extended periods of leaf wetness with heavy morning dews favor the disease. Fortunately, turfgrass can recover from brown patch in most cases, though it may take two to three weeks depending on weather.
There is no way to eliminate brown patch from a lawn, as it persists indefinitely in the soil. And while you can't eliminate the fungus, cultural practices can help control it.
Avoid watering in the evening to decrease the number of hours leaf tissue remains wet. Avoid overfertilizing, and don't fertilize when brown patch is active. Keep seeding/overseeding rates lower, too.
Fungicides can be effective in preventing brown patch, but the two most commonly used products (Heritage and ProStar) are expensive and not available in small quantities to the general public. Instead, you may have to try products like triadimefon (Bayer Fungus Control for Lawns and Green Light Fung-Away), propiconazole (Fertilome Liquid Systemic Fungicide) and myclobutanil (Immunox).