GrowthWatch: Focus switches to second-cut silage and surpluses
By Teagasc’s Seán Cummins and James Fitzgerald
After a challenging few weeks in terms of drought, the farms in the Teagasc Green Acres Calf to Beef Programme are now in a position of surplus grass once again.
The focus for this and next week has firmly switched to getting second-cut silage crops saved and back into the yard, and on collecting any surplus grass from paddocks.
In terms of the second-cut silage, crops have bulked up really well in most cases during the last three weeks. However, the grass to stem ratio is lower than desired in some cases as a result of grass being stressed up until mid-June.
At this point, and before quality deteriorates completely, it’s important to get this crop saved and added to the winter feed supplies.
Unlike other beef systems, there’s no scope for inferior-quality silage in calf-to-beef systems and it’s worth remembering at this point that the daily meal feeding rate for weanlings on respective silages of 75% dry matter digestibility (DMD) and 65% DMD differs by nearly 180kg over a 120-day winter.
Some farmers are questioning on whether or not grass is still high in nitrogen (N) and what potential impact this may have on fermentation.
Typically, grass takes up 2 units/ac/day of nitrogen (N) in ideal growing conditions. However, the weather since fertilisation has not been sufficient for this to occur in some cases.
To see if grass is suitable for cutting both the sugar and nitrates levels need to be tested prior to harvesting. Ideally, the sample of grass should be taken in conditions that mirror those of when the mower enters the field and ideally from midday onwards, when sugars are at the highest levels.
In addition, with the growth rates that have been seen over recent weeks, many of the Teagasc Green Acres farms are in a position of surplus grass on the grazing platform.
When the second-cut silage crop is being harvested, this might be an opportunity to remove this surplus grass and add it to the winter feed stack in the yard.
- Growth: 43kg DM/ha/day;
- Demand: 37kg DM/ha/day;
- Average farm cover: 557kg DM/ha/day;
- Stocking rate: 3.38LU/ha.
The farm has turned a corner over the last couple of weeks; what looked to be a severe drought situation turned back around once rain arrived.
Last week, the farm grew 43kg DM/ha/day, while demand stood at 37kg DM/ha/day, so we are back in a position of surplus once more.
I took a number of steps to reduce demand once a drought looked imminent, including: upping the meal supplementation rate to calves to 2kg/day; introducing concentrates to finishing steers at grass; and moving any cattle that were finished off grass as quickly as possible.
The farm is now in a position where the meal supplementation to the calves can be reduced back to 1kg/day once again. We’ll assess to see whether meal supplementation will continue after the mid-season weighing is completed.
There are also more 28-month steers to be slaughtered over the next week or two, so this should set the farm up nicely for the remainder of the year.
I’ve upped calf numbers by 20 this spring, so the target for the remainder of the year is to collect as much surplus bales as possible to have a fodder surplus in the yard going forward. That way, if a wet spring/autumn comes, we have sufficient fodder in the yard to get us through.
I also harvested the second-cut silage last week. The crop was really beginning to lose quality on account of the stress it experienced during the drought – even though it was only growing since May 20 – so the decision was made to cut and bale.
In terms of fertiliser, I’ve topped up all of the grazing ground with 27 units/ac of N over recent days. The decision was made to limit fertiliser applications during the dry spell and wait to see what way grass would respond to the organic N that would have been released.
- Growth: 81kg DM/ha/day;
- Demand: 39kg DM/ha/day;
- Average farm cover: 812kg DM/ha/day;
- Stocking rate: 2.77LU/ha.
Grass growth rate has really picked up here over the last couple of weeks, resulting in a growth rate of 81kg DM/ha for this week, which is the highest so far this year on my farm.
In order to keep up with grass and keep a nice leaf in front of the cattle, I have been cutting and baling three-to-four paddocks each week for the last fortnight.
This has provided three-to-four bales/ac of top-quality silage for this winter, as well as maximising cattle thrive at grass.
I have been spreading roughly 18 units of N after each grazing up to now, with the majority of this being in the form of protected urea. This has now been stopped and the plan is not to have to spread N again until well into August.
For the next few weeks, I’m aiming to keep my cattle moving into covers of 900-1,000kg DM/ha of aftergrass so that clean outs will be as good as possible.