As autumn draws in, there is plenty of planning to do for the remainder of the grazing season and indeed the wintering period.
The first job on the to-do list is to review the grass budget.
Each year, many farmers seek the answer to one of life’s great mysteries; ‘What do I close my farm at?’
It shouldn’t be a mystery; how many of us look at last year’s grass walks, look at average growth rates for September, October and November and then re-read the comments we made at each walk, usually telling ourselves how we should have started closing earlier, or built up a higher/lower peak cover in mid September?
Go through this information for the past few years and you will have your answer.
A grass wedge is not useful at this time of the year as it tells us what we have to date, not what we need next week or next month.
So you need to set up your grass budget as soon as possible if you have not already done so.
Which paddocks to close first?
On northern farms, paddocks grazed from early October will not be grazed again this autumn.
Paddocks grazed now will be grazed again before the end of the grazing season and so we should have a think about what paddocks we want to graze first in spring.
We also need to think about the heavy-soil type paddocks that we may not be able to graze until late spring.
On farms were silage ground is accessible to cows for grazing, it needs to be kept in mind that this ground will have to be grazed in early February.
At turnout in February, cows will be trained to graze covers of 700kg/ha to get them back grazing again and to supply this grass the paddocks will be closed on October 20. We also need to close 60-70% of the farm in the first 30 days of closing (e.g by November 1).
Paddocks closed first will have the greatest cover come spring, they will be grazed by mid-late February.
On heavy soil farms, it is important to consider what fields may be dry enough to apply slurry on in February.
Closing paddocks for spring grass
Farms in the northern half of the country will begin closing paddocks from late September, owing to lower growth rates in autumn, winter and early spring.
Southern farms will close anytime from the beginning of October to mid October. Two factors that decide closing date are:
1. Target opening cover in spring.
2. Winter growth rates.
We cannot have a target closing cover without first calculating our opening cover; how much feed we need next spring.
Programmes such as Agrinet, have a built in calculation to work out how much feed cows will consume per day (kg pf Dry Matter) post calving.
All you have to do is enter how many cows are to calve each week for next February, March and April.
As many of farmers have now scanned their cows, they know roughly how many are due to calve weekly from early February onwards.
Adjust projected growth rates to suit your farm and enter in any supplements required to make your average farm cover (AFC) equate to around 140kg/LU by magic day.
What covers should you aim for?
As mentioned above, closing AFC’s will range between farms. In Tyrone, we aim to close at 700kg/ha by mid-November, which will have us opening in late February at circa 850kg/ha.
The highest covers we will carry over the winter are 1200kg/ha.
If weather turns very wet, we will prioritise grazing the heaviest covers but it would not be uncommon to have to carryover a high cover (1600-1700kg/ha) if ground conditions turn against us.
The disadvantage of carrying over such a cover would be low/zero winter growth and poor regrowth post grazing in spring.
On drier farms down south, farms will typically close at around 650-700kg/ha by late November and open at more than 850kg/ha next spring.
It is imperative that we close the farm up at the correct cover as this has a huge effect on financial performance next spring.
Meal and silage needed if grass is in short supply
If we haven’t sufficient grass covers, we will have to feed more silage and meal.
This spring, many farms fed poor quality silage and low amounts of meal which stripped condition off cows backs and had a negative effect on fertility, specifically three-week in-calf rate, as cows had less energy available to get in calf early.
We must maximise the proportion of high quality grazed grass in the early lactation diet so cows have sufficient energy to cycle, express heats and get cows back in calf.
Grass budgeting
Once farmers have a grass budget set up that is relevant to their farms, they will need to adjust it after each weekly walk.
The growth rate figures from weekly farm walks are not automatically transferred into our budget, so we enter these manually.
Don’t forget to update cow numbers, level of supplement, (if any) and grass demand per cow at each walk.
Do the sums on empty cows
Scanning results have been good overall, however any empty cows must be culled immediately if grass supply is not sufficient.
If grass supply is adequate, then could we sell these cows and reduce the amount of supplement we are feeding?
Example: If we have a 100 cow herd and 10% scanned empty; removing these 10 cows from the platform will add 160-180kg (16-18kg/cow) of grass to the other 90 cows – this is almost 2kg of Dry Matter per cow so it is quite substantial.
Do your own sums on the economics of it but with milk price so low, these passengers certainly aren’t going to drive much in the way of profit.
