Theres too much grass even though cows went out early
Maximising use of grazed
grass, and getting cows out
early, is starting to pay off
on one Dorset dairy unit.
Jessica Buss reports
DESPITE turning cows out in early February and grazing the whole grass area including silage ground by the end of April, there is still too much grass ahead of the 150 spring calving cows at Nick Findings Rainbarrow Farm, Martinstown, Dorchester.
Herd manager Clyde Jones told a local BGS grazing discussion group which met last week that cows are now grazing tightly, leaving swards at 1400kg DM/ha to ensure high quality regrowth, and supplemented with silage at 2-5kg a day, depending on the weather.
The extra feeding is only being continued because of poor weather to maintain cow conception rates, stresses Mr Jones. Cows not confirmed in-calf receive 2-2.5kg/day of concentrates through out-of-parlour feeders. Serving started on Mar 29, and although cow condition was one score lower than last year, cows were bulling well and holding to service.
"By the end of April, grass growth was increasing and some of the grazing area is now beginning to get too long for grazing," says Mr Jones.
Some group members farming heavier clay soils, had also been forced to keep cows in by day for several days and were now more concerned than Mr Jones that their grazing was getting ahead of cows.
BGS grazing consultant Paul Bird says that Mr Jones was right to graze tightly to achieve good quality regrowth rather than try to clean it up in May or June. However, leaving slightly higher residuals after grazing over the next month would increase the speed of the rotation in order to enter paddocks with a cover below the 3000kg/ha DM target. This could reduce the area needing silaging to control grazing cover.
"You can leave residuals up to 1600-1800kg without any problems, but dont go above 2000kg. Then budget to keep two weeks grazing ahead of cows and cut the rest for silage.
"When cows will not solve the problem of too much grass and with fast growth rates in May, a mechanical solution will be needed." This could be topping grass after grazing or cutting for silage.
An alternative was to use a leader-follower grazing system to lower residuals after cows leave paddocks, but in wet weather this increases the risk of damaging pasture.
Mr Jones rotationally grazes the herd using temporary electric fencing, running cows across one paddock to reach paddocks further away when necessary. This is a practice cows soon get used to, he says.
"Cows first stayed out by night on Mar 12, but were housed overnight during wet weather." The farms chalky soils and tracks that were built last winter, from farm-sourced chalk, allowed cows to continue grazing some grass by day and to go out at night again fairly quickly.
Clyde Jones (left) tells Paul Bird cows are grazing tightly, to 1400kgDM/ha.
• Tracks allow access in wet.
• Graze tightly for quality regrowth.
• Block calving simplifies management.