A Little Water and Time Go a Long Way to Reclaim Desert RangeBy Don Comis
November 5, 1998
Over the past 86 years, U.S. Department of Agriculture scientists have begun to think in terms of desert time as they try to re-establish native plant species on nearly 200,000 acres of desertified rangeland in New Mexico.
Lack of water is the prime reason plants grow and spread slowly in the desert.
But scientists with the Agricultural Research Service, USDAs chief scientific agency, have learned how to take advantage of occasional rain. For example, they designed packages of seed-filled pipes that are placed in shallow rills so that, when rains come, seeds are washed out.
The rainwater breaks through crepe paper on one end of a seed-filled pipe glued to the bottom of another 4-inch diameter pipe. The force of the water pushes seed through a mesh screen. With enough rain, the water frees seeds from similar pipes glued to the middle and top of the package pipe.
The stream carries the seed farther away and provides a moist seedbed. It also deposits bits of grass and shrubs, providing a mulch cover for the seeds.
At 75 cents each, the seed package is the type of low-input natural trigger that exemplifies the new philosophy at ARS Jornada Experimental Range near Las Cruces, N.M. This philosophy, developed by ARS rangeland scientist Kris M. Havstad and colleagues, relies heavily on trigger sites like the rill. These sites have some natural advantage, usually access to water, where a little time and money go a long way to encouraging the spread of protective grasses and other ground cover. Havstad and his colleagues monitor the trigger sites to see if plants are spreading outward.
An article on the Jornada research appears in the November issue of ARS Agricultural Research magazine. The article also is on the World Wide Web at: