Weekly Grassland Management Diary of Robotic Grazing Farm – 28th June (week 27)
- Growth 70.8kg DM/ha (35.5)
- AFC 592kg DM/ha (568)
- Cover/cow 180kg DM (166)
- Demand/ha 49.5 kg DM/ha (58.2)
- MS/cow 2.09kg (2.02)
- Fat 3.97% (3.84)
- Protein 3.53% (3.48)
*previous weeks Grassland Management figures in brackets
Last week, cows grazed out A4, A5, C10 (C11 grazed by bullocks), C1 and B6. They are going through the A paddocks quickly as they are lower covers. Cows are doing a good job of grazing out paddocks even with the stemmy grass. The farm got 8mm of rain all week. The Nitrogen spread 2 weeks ago must have been taken up by the grass; growth rates are up at 70kg DM/ha and milk solids have increased by 0.7kg. The milk protein has increased mainly due to the N taken up by the grass, even though it is stemmy.
The A paddocks had growths of 64kg DM/ha; this will be low this week with the forecasted weather (A paddocks are sloped and burn up faster than B&C). Because of this, the times going into A will be reduced (5pm-10pm) and getting a bale of silage. We aim for the cows to take in 2kg DM of silage and 2kg DM of grass in A; the other 13kg DM of grass will come from B and C. The covers in B (AFC 690) and C (AFC 656) are above the target PGY but this will balance out the low AFC of 400kg DM/ha in A. We need to increase A covers by slowing down the rotation with bales.
High temperatures are forecast for the week (>20°C) with no rain in Leinster. This will reduce growth rates especially if there is no cloud. Hopefully the grass is still taking up the N to keep protein up. Growth rates will drop to around the 30-40’s kg DM/ha. The rotation length will stay at 26 days. The cover/cow has increased and the aim is to increase it further. An extra 2.8ha will be available for grazing in the next 10-14 days. We expect the milk solids to drop as we are introducing baled silage and all grass is heading out; the N spread may keep milk protein up slightly higher. Clover accounts for 60-80% of the covers in the B paddocks. Stemmy grass has an UFL value as low as 0.85 with clover staying at 1UFL; clover also has a CP content of 22% and a high digestibility of 80%. This should help keep milk solids from dropping too much.
Jordan Molloy – Grazing Consultant, Grasstec
“I teach farmers how to measure grass and the discipline needed to do weekly farm walks. I show them how to input their data onto Agrinet and how to understand the grass wedge. Each week presents a different scenario on the farm so it’s crucial that the farmer can interpret the data in order to make informed decisions. Grasstec consultants are available in Ireland and the UK.”