Growth Watch: Rain to give much needed respite, but challenges persist
The extended dry spell has posed many challenges to the farmers in the Teagasc Green Acres Programme. James Fitzgerald & Séan Cummins, Teagasc GreenAcres Advisors, give advice on dealing with cattle in different weather conditions. They also get farm updates from JP Hammersley & Irvine Allen.
The Advice
Daily grass growth rates on the farms from this week to last have dipped by 9kg DM/ha/day – from 64kg DM/ha/day back to 55kg DM/ha/day, while the average farm cover has reduced back to 642kg DM/ha.
Farmers in the south and east of the country have been hardest hit, while those on heavier soil types have had sufficient moisture to maintain growth rates.
This is evident in the growth rates being witnessed at farm level. Although many are still ahead or on a par with demand – with growths in the region of 50-60kg DM/ha/day – the lowest growth rate recorded this week was 15kg DM/ha/day.
Grass quality has also deteriorated somewhat over the past week, with stressed grass plants sending up seed heads in response to the dry conditions.
Although the extended heatwave has reduced growth rates and seen some farmers supplement with silage, the expected rain this week will help correct the situation in time. However, this depends largely on the quantities that arrive.
Many areas of the south and east of the country are currently in soil moisture deficits of 50-60mm and, with rainfall quantities of less than 25% of this expected in some regions, growth may be restricted until further quantities of rain arrive.
Where sufficient volumes arrive to correct soil moisture deficits, careful monitoring of the grass situation on farm will have to continue over the coming days. The need to supplement may continue, but the basis of silage inclusion must be made on grass growth rates and the farm’s average farm cover.
Where stores are sufficiently forward, there may be an opportunity to introduce concentrate feeding earlier and have these animals moved off farm prior to housing in November. Not only will this action somewhat reduce the demand from grazed grass currently, the earlier sale of animals will reduce the quantity of silage required in the winter feed arsenal.
In the dry weather conditions, cattle were relatively settled on account of the high dry matter content of the grass. However, this is likely to change over the coming days, as additional moisture may see grass dry matter levels dip and cattle become unsettled.
Ground conditions are exceptional in many locations, but with heavy rain expected this week, this could change on heavier farms relatively quickly – especially those in the south west of the country that received rain last weekend. Where this does occur, moving cattle every 12-24 hours may be required to avoid causing damage during periods of heavy rain.
Depending on the quantities of rain received, many farms may be exiting a soil moisture deficit and, as fertiliser applications were skipped during the dry spell, there may be an opportunity to provide nitrogen to grass in the form of protected urea. After the dry spell, there’s a likelihood that some organic soils will release organic nitrogen if soil fertility is adequate, so careful monitoring of growth rates over the next two weeks is necessary to maintain targeted pre-grazing yields of 1,500kg DM/ha ahead of stock.
Another consideration after the rain is ‘coughing cattle’ and animals must be monitored for symptoms of lungworm in the 7-10 period after rain.
JP Hammersley, Lattin, Co. Tipperary
Growth: 45kg DM/ha/day- Demand: 48kg DM/ha/day
- Farm cover: 815kg DM/ha
- Stocking rate: 3.52LU/ha
Growth and demand are finely balanced here in Lattin and, with rain expected this week, the farm should be in a strong position to build autumn cover going forward.
Second-cut silage was harvested just over 10 days ago and I have this ground closed for a third cut.
If growth remains slow and the farm cover begins to dip, I have a couple of options to counteract this. Firstly, 20 of the 2020-born steers weighed over 520kg in early July.
The long-term plan for these animals is to have them slaughtered before Christmas and if the need arises they are heavy enough to supplement with concentrates at grass in the next week or two.
Secondly, one third of the silage ground received a reduced rate of nitrogen and there’s the option to graze this down the line to slow down demand and extend the rotation.
18ac of reseeding was carried out over the weekend and with rain on the way, I hope to be grazing this in approximately 40 days with 2021-born calves.
Irvine Allen – Moate, Co. Westmeath
Average farm cover – 1028 kgDM/ha- Growth – 39 kgDM/ha/day
- Demand/ha – 33 kgDM/ha/day
- Stocking rate – 1.67 LU/ha
The last couple of days have seen the first significant falls of rain in weeks on this farm. On the out block where most of the yearling cattle are grazing, reserves of grass were beginning to run a bit tight. The rain should boost on grass growth across the farm and prevent the need for feeding out silage to the grazing cattle.
Harvesting of the second cut silage will take place over the coming days. I am expecting this crop to return c.10 bales/ac which will leave the total bale count in the yard at 850-900 bales.
With lower than expected grass growth rates experienced for large spells of the grazing season so far, less surplus bales have been harvested than what I would have expected.
The total amount if bales needed for the winter is 900 so at present there is still likely to be a small shortfall after the second cut is taken. The grazing ground at home which is being measured on Pasturebase is likely to return more surplus bales before the growing season is finished due to the low demand for grass here and the high average farm cover there is here currently.
The majority of the land here is low in Phosphorous and so I am spreading 18-6-12 as 1 bag/ac on all of the grazing ground. The remaining reserves of slurry will also be used on the silage ground in the coming month when a clean graze out of aftergrass is achieved.
The Teagasc GreenAcres Programme Advisors have regular contributions here on Teagasc Daily. Find out more about the Teagasc GreenAcres Calf to Beef Programme here.