Continued wet weather on project farms over the past week has made programme farmers take various measures to manage the changing grazing conditions while planning for autumn.
The two farms in Co Cavan have been selecting drier paddocks for grazing and back-fencing cows to limit damage to grazed areas.
Housing dry cows has reduced pressure on the grazing block on both project farms in Co Tyrone, while allowing the remaining milking cows to stay at grass.
A recently constructed hardcore lane on Nigel Corbett’s farm near Banbridge, Co Down, is helping to reduce poaching on the way to and from the parlour. However, the weather broke before some finishing touches were completed.
Well-positioned laneways give cows best access to paddocks, additional drinkers and adequate electric fencing allows back-fencing and multiple entry points to paddocks reduces poaching at gaps.
Grazing conditions
The benefits of good grazing infrastructure are often only realised when grazing conditions get difficult.
A dry spell before the recent wet weather allowed third-cut silage to be made and surplus grass to be taken out of the grazing platform on programme farms.
Although silage-making has stalled, several programme farmers have paddocks with surplus grass earmarked for silage for when conditions improve to keep cows on good-quality grass.
Plans are also in place to get fertiliser spread and lengthen rotations by opening silage ground for grazing to allow adequate covers to be built up for the autumn.
Supplementary silage is also being fed after milking on some project farms to lengthen rotations.
Developing good grazing infrastructure, baling surplus grass and lengthening rotations as growth rates tail off all have the same aim – to extend the length of time that good-quality grazed grass remains in cows’ diets.
With recent wet weather making grazing more difficult on heavier paddocks, we have started being selective on where cows are grazing, as certain areas of the farm have heavier soils than others. Surface water has been slow to drain off, but poaching has been minimal so far. Milking cows have been moved from 24-hour to 12-hour breaks to improve clean-outs.
A recently constructed hardcore laneway around 300m in length has been useful for stopping damage when cows are walking.
We are keen to get the laneway finished by rolling it and putting on a light covering of 2in crusher run, as there is still some clay content in the lane which could get mucky.
Getting fencing along the laneway completed and adding extra drinkers in paddocks will give us more options for back-fencing cows to stop poaching in areas that are already grazed.
Autumn plan
An autumn grazing plan is under way to keep cows at grass for as long as possible over the coming months and to set up the grazing block for next spring.
The final rotation will start on 1 October and 65% of the farm will be grazed by the end of October. If weather permits, the remaining 35% could be grazed in early November by late-lactation cows or young stock.
The target is to get residuals down to 70kg DM/ha to allow good-quality regrowth over winter with an average closing cover of 650kg DM/ha.
The grazing platform has now been extended to 31ha with the addition of 7ha of silage ground. This brings rotation length to 30 days to build covers as growth rates reduce.
We also plan to blanket-sow the whole farm with fertiliser before the closed period for spreading fertiliser starts on 15 September.
The target average farm cover is 1,000kg DM/ha for 1 September and this will increase slightly during the month to reach 1,100kg DM/ha for the start of the last round on 1 October.
Although we are in the process of building average farm cover, one paddock of heavy cover is to be taken out for bales once the weather improves. T
his will allow us to keep cows in good-quality grass and will still let us hit autumn grazing targets with the silage ground opening.
Reseeding is also to be carried out when conditions improve, with six acres of the grazing block currently burned off with glyphosate.
Farmyard manure will be spread and ploughed in with a mixture of intermediate and late tetraploids (Abergain and Astonenry) and diploids (Aberchoice and Abermagic) to be sown.
Winter feed
The winter feed budget set out in Table 1 is based on bales with 25% DM and weighing 0.75t. The weight of silage in the pits is calculated for 30% DM silage by multiplying the length, width and depth of the clamp in metres and dividing by 0.6.
Between two silage clamps and 91 round bales, we have around 1,200t of fresh-weight silage in stock, which leaves us well set up for winter.
Around 40% of the herd are now dry and the first cows are due to calve from 5 September. Three-quarters of the herd are due to be calved by the end of December and the remaining 25% in January.
We are currently considering options for some additional calf accommodation this year, with more calves coming in a shorter window.
This is due to the calving spread continuing to tighten from eight months in 2015/16 to five months this year and herd size increasing by 20 cows this year.
Some options include converting existing solid floor sheds, buying calf hutches or constructing homemade calf shelters.
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