Express-News

Saturday, May 29, 2004

By Calvin Finch, Conservation Director, SAWS, and Horticulturist

BUFFALO GRASS

            Buffalo grass is our only native option for a lawn grass. Bermuda grass and zoysia grass are well-adapted exotics. St. Augustine grass is a less well-adapted exotic having evolved in high rainfall areas with acidic soil. You may be disappointed with buffalo grass as a lawn grass choice, however, unless you know exactly how it performs best and manage it well. You have several choices for management of your buffalo grass. Your first choice is to attempt to use it for a low water use grass with a manicured look. The second, and I think the best choice, is to use it as a groundcover with limited mowing.

            Buffalo grass has a large range across North America. It lives from Mexico well into Canada on the rest of the prairie from San Antonio west to the Rockies. It is at its best in the areas with about 20 inches of rain on heavy alkaline soils in full sun. It survives through droughts and cold weather by an ability and inclination to go dormant. When conditions improve it greens up quickly. Nowhere in its range does it make a thick sod. There are relatively few plants per unit area even in locations where nearly pure stands exist. It does not make a sod like zoysia, St. Augustine, or Bermuda grass.

            To use buffalo grass as a manicured lawn requires that you address the lack of density. If you mow buffalo grass at 2 or 3 inches tall there is lots of bare ground on which weed seeds can reach the soil and receive adequate light to germinate. A tactic to keep the weeds from germinating is to use a pre-emergent herbicide like Amaze or XL every February and August. It prevents the weeds from germinating. It is also essential that the lawn not be over watered or over fertilized. Buffalo grass is not a great competitor. It can survive on about .75 inches of water every two weeks applied in weekly amounts of about .4 of an inch and one fertilization in May. Slow release lawn fertilizer like 19-5-9 applied at the rate of 1 lb. of nitrogen per 1000 sq. ft. (5 lbs. of fertilizer) works adequately. Apply too much water or too much fertilizer, and the weeds,  especially Bermuda grass, will be tough to control. Once Bermuda grass is established it is very difficult to remove it from a buffalo grass lawn. You can work at it by hand but contact herbicides are no help. The same chemicals that kill Bermuda grass will kill buffalo grass.

            The second option for buffalo grass is to use it like a groundcover. It would be most effective on a slope with a western or southern exposure. The grass would not be mowed on a regular basis. Mow two or three times a year at 5 inches or as high as the mower will cut. The tall grass helps prevent weed seeds from getting enough light to germinate. The occasional mowing helps keep perennials and tree seedlings from reaching a large size. The grass reaches 7 or 8 inches tall and weeps over; it can be attractive in the right situations.

            In addition to encouraging weeds, watering buffalo grass excessively can actually kill the grass. Buffalo will also not tolerate a winter grass like rye or fescue being planted into the lawn for winter color. The soil seems to stay too moist and a large portion of the buffalo grass roots rot before spring. In some cases, however, wildflowers will work well. Neither wildflowers nor buffalo grass require supplemental irrigation in wintertime.

            Buffalo grass can be seeded but it is not as quick to germinate as Bermuda grass. Full germination may require 5 or 6 weeks. There are several choices in buffalo grass sod. Stampede, 609, and Prairie are the easiest to find. They are vegetatively reproduced female plants. The single-sex sod selected from superior stands form a more uniform, greener, and thicker sod than the seeded lawn with both male and female plants.

            Buffalo grass may meet your needs. It is a low water requiring native grass that works better as a groundcover than a manicured lawn.