Tips on managing through dry June conditions
Despite a very dry start to June, average grass growth rates had been 60kg DM per day and farm covers had been holding well in most regions
However, as Joe Patton, Head of Dairy Knowledge Transfer explains, with soil moisture deficits heading >60mm in many areas, it is expected that grass growth rates will drop close to or below feed demand on many dairy farms this week. In this ‘green drought’ situation, a number of short and longer-term management steps are required:
- Up until last week, there was still plenty of grass on farms on average (>800kg DM per ha), but this situation could change quickly as growth slows. Walk the farm and complete a grass cover on PastureBase Ireland to assess the situation.
- It is important to hold average farm cover at 550kg DM per ha so that the farm can respond quickly when rain arrives. To hold farm cover for the next 7-10 days, bring daily grass allowance down to match growth. For example, if growth is down to 40kg DM per day, and the farm is stocked at 3.2 cows per ha, then 40/3.2 = 12.5kg grass per cow can be allocated. If the herd is 100 cows for example and grass covers is 1,400kg in the paddock, then the allocation would be 1,250/1,400 = 0.9ha per day.
- Hold rotation length to grazing no more than 4-5% of the area each day, and do not allow the grazing area to increase in response to lower grass covers. Use a strip wire.
- Keep the herd well fed where grass allowance is restricted. Aim for 18-19kg DM. In the example outlined (12.5kg grass), a further 6-7kg per cow supplementary feed is needed.
- This level (>6kg feed) is too much to be made up by parlour feeding alone. Offer some high-quality silage or high-fibre straights.
- If feed space is tight, offer a section of the herd some silage after milking (the first few rows out of the parlour etc) and allow the remainder of the herd to return to the paddock. The silage-fed cows can be let out after two hours to join the rest of the herd at grass and finish off the paddock. This will still slow the rotation, but make sure all cows are well-fed every day.
- Make sure fertiliser is up to date and that all paddocks due an nitrogen application are covered. Average growth rates justify this approach. However, do not ‘double up’ on areas that have been recently been spread and now have slowed growth due to lack of rain. Hold off until rain arrives
- Complete a winter feed budget ASAP to assess how much second cut and surplus silage will be needed to secure winter supply. If silage looks like it will be scarce, act early.