29 November 1996

Swearing by block systems in Wilts

BLOCK grazing is the key to maximising use of grazed grass by the 400 high merit cattle at Horton House Farm, Devizes, Wiltshire.

Speaking at the Malvern conference, Jon Rider stressed that his low input system depended on securing as much milk as possible from grazed grass at the 267ha (660-acre) dairy and arable farm.

Grass was the cheapest feed for his Holstein Friesians at £25/t DM compared with grass/maize silage at £75/t DM and concentrates at £175/t DM.

The January to March calving herd averages 5900 litres off 650kg of concentrates – and despite under 200mm (8in) of April to September rain in the last two years, milk from forage is 5000 litres.

Mr Rider said securing high intakes at grass depends on offering the cows a fresh feed every day. "Grazing consists of blocks of grass of 4-12ha which are grazed from the track using front and back fences. This ensures that cows are only on the same piece of grass for one grazing. Regrowth is protected, poaching minimised and the cows clear up the pasture."

The grazing rotation is 21-25 days, grazing grass at 3000-3500kg DM and grazing down to 1400kg DM, he explained. Care is taken to offer cows a dense, leafy sward that will satisfy intakes of 18-19kg DM a day in spring.

"We cut for silage within the grazing block, or top before grazing when necessary to remove rejected material from the sward so that cows have clean pasture on the next round," said Mr Rider.

To make better use of grazed grass he plans to calve three weeks later next season. "The cows will need less silage in January before calving which will take the pressure off silage making in spring."

for silage making in spring. Calving later will also ensure an adequate supply of young grass in front of the cows at this critical time and enable us to build up a feed wedge for the summer drought."

The policy will also reduce straw bedding requirements and concentrate use. "And it will mean AI is when the cows are settled on grazed grass rather than coinciding with turnout. This should improve conception rates and will cut labour requirements."

Block grazing techniques enable Jon Rider to ensure cows at Horton House Farm are only on the same piece of grass for one grazing.