NMSU branding

New Mexico State University

New Mexico State University

News Center

NMSU Seeks Drought-Resistant Grasses for Disturbed San Juan Basin Lands

FARMINGTON - Replanting lands disturbed by oil and gas operations in northwestern New Mexico requires grass varieties that are fast-growing and drought-resistant, but only moderately appealing to cattle and wildlife so stands won't be devoured before they can grow.

To find the right balance, New Mexico State University's Agricultural Science Center at Farmington began testing some 30 native and nonnative grasses for growth rates, stand formation and palatability.

"Most of the varieties we're testing are palatable in varying degrees, but some are not at all," said Rick Arnold, pest management specialist at the center. "We want to find something in between that allows cattle and wildlife to continue grazing, but that's not so appealing that they just hang out on the reseeded areas."

Given the vast number of well pads and pipeline right-of-ways in the San Juan Basin, which straddles San Juan, McKinley, Rio Arriba and Sandoval counties, re-establishing vegetation is essential to protect against soil and wind erosion.

About 25,000 acres of land need revegetation, according to the Bureau of Land Management (BLM). Affected acreage could increase significantly because of expected changes in state and federal energy policies to encourage more natural gas and crude production.

The BLM works with companies to reseed disturbed areas, but grazing hinders the efforts.

"Many of the disturbed corridors that we're trying to reseed just get eaten away," said Dale Wirth, acting surface protection specialist with the BLM's Farmington field office. "The forage we've been laying down is like tender bean sprouts for the animals and they just come and camp out there."

In fall 2000, Arnold planted test plots at the center for 23 cool-season grasses that grow from early spring to late fall. In July, he will plant another nine warm-season grasses, which grow best in the hot summer months.

To mimic typical conditions in the northwest, plots receive about one inch of water per month, or 7 to 8 inches for the entire growing season. Arnold monitors rainfall and adjusts irrigation so that the monthly total usually doesn't exceed one inch.

"We're looking at stand establishment and yield to see how each variety fares under drought conditions," Arnold said.

In late summer or early fall, the center will replant grasses from test plots on disturbed sites in the San Juan Basin to see how they do under natural conditions. The BLM will choose three test sites at different rainfall levels and elevations, Arnold said.

"We'll rate the stands from poor to good on a scale of 1 to 9, examining establishment, height, yield and how much each stand was reduced by grazing," he said. "We'll go with the ones that grew well and didn't get eaten away."

Arnold said research will continue for at least three growing seasons to provide fodder for recommendations on the best varieties and planting times.