Managing Grass Supply In Rapid Growth
UK - Although April is normally one of the drier months of the year we still have had an extraordinary month of April this year.
1 May 2007
2 minute read
With nitrogen application coinciding with good growing conditions there is likely to be above average growth rates. Overall stocking rates have fallen in recent years as a result of higher live exports of calves and weanlings and a reduction in dairy cow and ewe numbers. It appears therefore that pasture supply will outstrip demand, leading to a rapid build-up of surplus grass, reduced quality and wastage later on unless there is timely management of grazing pastures. During a period of rapid growth the pasture supply/demand situation can change in a matter of days so we need to be alert to this and be ready to take remedial action if necessary.
The main task now is to spot whether the supply is rising faster than the demand. This requires constant monitoring in May and June. There are some indicators that help to maintain a good balance between pasture supply and animal requirements. As a rough guide, good pasture starting off with 7-8cm of grass in early April should carry 2,000-2,500kg liveweight/ha (800-1,000kg/ac) from April to July while allowing for the normal increase in weight gain over the period. Estimate the total weight of livestock you have on a specific area of ground. If there is substantially less than the 2,000kg/ha you can expect a surplus to build-up. Make allowance for poorer quality land by adjusting all the grazing area to the equivalent number of good hectares (adjusted acres).
Rotational grazing provides earlier signals of an emerging surplus and better control measures than continuous grazing or set stocking. However, with either system, dealing with grass over-supply requires a reduction in the grazing area or an increase in the stocking rate.
Normally in early April you need about 14 grazing days ahead of stock to be comfortable that the supply can cope with difficult grazing conditions (poor growth or wet soils). In good growing conditions, as at present, 10-12 days is adequate and if the grazing days ahead goes above 16-18 some remedial action should be taken to prevent an accumulation of mature stemmy pasture.
Source: BusinessXtra
