Growth Watch: Remember to replace what you take off
This week's GreenAcres Growthwatch comes from the farms of Pat Collins, Co. Cork and Martin Connolly, Co. Roscommon. James Fitzgerald & Seán Cummins, Green Acres Advisors provide advice on replacing what you take off. A typical bale of silage contains 10 units of N, 1.6 units of P and 10 units of K
Remember to replace what you take off
Steps taken to maximising grass quality throughout the mid-season usually include taking surplus bales off of grazing paddocks that get ahead of stock. This helps to gather additional silage of the highest quality while helping to keep the average farm cover in check. However one aspect of this management method which is often overlooked is making sure that you replace the P & K that was taken away in the form of surplus bales.
A typical bale of silage contains 10 units of N, 1.6 units of P and 10 units of K
A typical bale of silage contains 10 units of N, 1.6 units of P and 10 units of K. When surplus bales are removed, four to five bales of silage per acre will remove six to eight units of P/ac and 40 to 50 units of K/ac. A light application of slurry (1500 gallons/ac) or an equivalent compound fertiliser such as 0-7-30 is needed to replace what is taken away in the surplus bales in order to avoid a depletion in soil fertility.
Pat Collins and Martin Connolly
Farmer focus: Pat Collins, Castlemartyr, Co. Cork
- Growth: 33 kg DM/ha
- Demand: 44kg DM/ha
- Average farm cover: 505kg DM/ha
- Stocking rate: 4.4LU/ha
- Days ahead: 11
The lack of moisture over the last number of weeks has resulted in growth rates slipping significantly on the farm here.
With what looked to be a ‘green drought’ arriving, I made the decision to buffer feed cattle at grass with surplus bales. This helped to bring growth and demand in line and to protect the average farm cover.
Although the rain did arrive over the weekend and into the early part of this week, I’ve yet to see any major recovery in growth. A growth rate of just 33kg DM/ha/day was recorded on Tuesday.
To counteract this, the inclusion of silage in the diet will continue until growth rates begin to match demand again. I will complete a walk again later this week to assess the situation and to see will I continue or discontinue buffer feeding.
The farm is primed to grow grass at this stage in that the average farm cover was protected, but it will just take a few days for the moisture we received over the last couple of days to bring growth and demand in line once again.
Farmer focus: Martin Connolly, Castleplunket, Co. Roscommon
- Growth: 36kg DM/ha/day
- Demand: 40kg DM/ha/day
- Average farm cover: 857kg DM/ha/day
- Stocking rate: 2.69Lu/ha
- Days ahead: 21
A growth rate of 36kg DM/ha/day is well below average for what you would expect for this time of year. However, I am not in a situation where I need to worry about this as the average farm cover is quite high at 857kg DM/ha even with the strongest 3 paddocks earmarked for cutting and baling.
The demand for grass can also be substantially reduced at any time due to the bull beef system I run. The heaviest bulls are due to be housed shortly for finishing which can take the pressure off of grass when necessary. Surplus bales that were made earlier in the summer will make up the base of the bull finishing diet. This will negate the need to go opening the silage pit until later in the summer when more cattle are entering the shed.
The calves born this spring are thriving well and developing good appetites for grass. Keeping high quality grass (8-10cm) under them is a major focus for the rest of the summer and should help in continuing to achieve good weight gain.
The second cut silage crop is growing well and will be cut in the next week once weather allows. A delay in cutting would mean a reduction in silage quality which is something any calf to beef farmer has to avoid.
If you liked this Growthwatch article you might like to keep up with the weekly Growthwatch articles from the Teagasc Green Acres Calf to Beef team here on Teagasc Daily. You might also like to read the second issue (June) of the Teagasc Green Acres Calf to Beef e-Newsletter here. The Teagasc Green Acres Calf to Beef e-Newsletter will issue fortnightly and you can read it here each fortnight on Teagasc Daily.
To find out more about the Green Acres Calf to Beef Programme click here https://www.teagasc.ie/animals/beef/demonstration-farms/green-acres-calf-to-beef/