| Mississippi Delta MSEA Volume 3, Issue 1, Page 2, First Semester 1997 |
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REPORTER
Volume 3, Issue 1, Page 2, First Semester 1997
MDMSEA Uses Switchgrass Filter Strips
In a test conducted at the MAFES Black Belt Branch Experiment Station, the effectiveness of filter strips in reducing chemical runoff was evaluated. Runoff plots were used to capture the filtered water for a defined area. In the event rainfall was not sufficient or timely, a rainfall simulator was used to supply the needed rainfall. The system was designed to capture all runoff water from the plots. The filter strips were shown to not only reduce sediment but also to reduce pesticides leaving the plots. Depending on the tillage system used, the amount of herbicide in runoff was reduced from twofold to fourfold by a 6-foot strip of tall fescue.
The MDMSEA project has provided the opportunity to establish filter strips in a watershed setting. These strips have been established at two sites in the Delta: Beasley Lake watershed in Sunflower county and Deep Hollow Lake watershed in Leflore county. Several types of vegetation have been utilized for these filter strips including fescue, millets, and switchgrass.
The switchgrass has the promise to be a good choice for use in the Delta. It is fairly drought tolerant and usually dormant when we experience backwater flooding. The variety used on the MDMSEA sites is ?Alamo? switchgrass (Panicum virgatum L.). The USDA Plant Material Center at Coffeeville, Mississippi has experimented with this variety and has had favorable results. This is a native warm-season perennial grass that occurs over much of the Southeast. It usually grows 3 to 5 feet high. The leaves are ?- to ?-inch wide. The plant has vigorous roots and underground stems. The stalks and stems are stiff and aid in its ability to filter runoff water.
The switchgrass was established using a no-till drill, planting 15 lbs/A of PLS at a depth of ? inch. No herbicides were used in establishment. Switchgrass is slow to establish and no fertilizer was applied at planting. This characteristic is valuable in that where strips have been established for several years little or no encroachment into the cropped fields has been noted.
With the benefit of reducing erosion and the reduction of chemicals leaving the fields, it is apparent that a filter strip is a valuable tool. Through the use of well-planned systems of filter strips, we can reduce the amount of sediments and pesticides entering our steams and lakes.
Ken Ainsworth
Conservation Agronomist
USDA-NRCS, Mississippi Area 4
Greenwood Area Office
Room 306, Federal Building
P. O. Box 1160
200 East Washington Street
Greenwood, MS 38935-1160
Phone: 601-453-2762
Fax: 601-453-7841
Editor's Note: The MDMSEA project would like to thank Dr. Seth Dabney (UDSA-ARS-NSL, Oxford, MS) for his generous donation of switchgrass sod used to more quickly establish some of the filter strips. The Project also thanks Jim Parkman and staff (NRCS, Greenwood and Coffeeville, MS) for planting the sod and Dr. Charles Ed Snipes and staff (MSU Delta Research and Extension Center, Stoneville, MS) for planting the switchgrass seed.
