25 August 1995

Dont reseed yet…

LIVESTOCK producers must avoid rushing into reseeding drought hit grass swards for most will recover when it does rain.

So says consultant Mike Dewhurst of Fieldfare Associates.

"Soil temperatures are high and any rain will release unused mineralised nitrogen held by organic matter in the soil and stimulate grass growth," says Mr Dewhurst.

"And because of the level of unused nitrogen, farmers should resist the temptation to apply nitrogen at the first sight of rain.

"Extra nitrogen could leach out, or be washed straight from soil surfaces and into watercourses as when the 76 drought broke.

"On grass leys where stock have pulled up shallow-rooted plants, there is an opportunity to reseed but first assess how badly damaged the sward is," he says.

The advice is echoed by ADAS grass consultant David Budd: "If a ley has produced good yields in the past leave it alone. Remember, there is always a one in 10 chance that a reseed will fail.

"It would be best to wait until it rains to see how much grass has been killed, and then patch up bare areas, or areas invaded with annual meadow grass, so there is enough grass for silage next year. Then reseed next summer," he says.

"If plant populations were poor on a ley that had a history of low yields, it was good to reseed." But Mr Budd urges producers to ensure there is sufficient soil moisture to maintain the grass seedlings through establishment. "A single shower will encourage seeds to germinate, and if followed by more dry weather, the seeds will be killed off," he says.

When conditions are right for sowing, crop consultant John Jemmett advises roughing up the sward surface with discs or a harrow, broadcasting the seed onto the sward, and rolling to conserve soil moisture.