Act Now to Assess Winter Feed Demand and Plan for the Winter Ahead
Guidelines for assessing and planning winter feed requirements for livestock, including calculating fodder needs and managing fertiliser allowances.
Do a Fodder Budget
Assess your winter feed demand based on how many animals you intend to keep for the winter period. The winter housing period will depend on your location, system and soil. Review the length of time you plan to keep animals indoors and allow a buffer for weather uncertainties.
Table 1: Guide to calculate the fodder demand on your farm
| Stock Type | Number of Stock(A) | Winter Months (B) | Tonnes of fresh weight of pit silage required per month (C) | Total tonnes required (AxBxC) |
| Dairy Cows | 1.6 | |||
| Suckler Cows | 1.4 | |||
| Cattle(>2 years old) | 1.3 | |||
| Cattle(1-2 year olds) | 1.3 | |||
| Cattle(0-1 year olds) | 0.7 | |||
| Ewes | 0.15 | |||
| Total fresh weight tonnes of fodder required (pit silage) | ||||
| Total bales required (multiply by 1.4) | ||||
Measuring winter feed supplies
Pits should be measured (length x breadth x average height in metres) to calculate volume of silage. The estimated feed in the pit will vary due to dry matter. Drier silage will have less fresh weight per cubic metre but will actually contain more feed due to reduced water content.
Table 2: Estimated fresh weight of forage per cubic metre of settled silage pits (based on 22% DM silage)
| Silage Pit | Length (m) (A) | Width (m) (B) | Average Height (m) (C) | Total Volume of Silage (m3) (AxBxC) |
| Pit 1 | ||||
| Pit 2 | ||||
| Pit 3 | ||||
| Total volume of silage (m3) | ||||
| Total fresh tonnes of silage (multiply by 0.74) | ||||
| Total number of silage bales in stock | ||||
Compare your feed requirements (Table 1) with your stocks (Table 2) to assess if you have sufficient feed in stock and take action if needed.
Act now to fill a potential feed gap
Options if you anticipate a winter feed deficit:
- Use remaining N & P allowances to:
- Increase growth on grazing ground and take out surplus bales
- Grow a 3rd cut of silage
- Use slurry (LESS) to increase NPK supply to paddocks and silage area.
- Increase grazing rotation length to 25-30 days in August to build grass and extend autumn grazing.
- Rent land for a 6 to 8 week period for 3rd cut.
- Source silage or hay for sale.
- Feed concentrates at grass to cattle that are close to finish.
- Look at the option of growing forage crops.
- Purchase whole crop or maize silage.
- Purchase beet (where you have appropriate machinery to feed).
- Sell some stock earlier than planned including cull cows.
- Finish some stock on minimum roughage and ad-lib ration.
- Complete a cash flow budget and seek additional finance early.
Assess your Fertiliser Allowance
- Farmers are required to operate within fertiliser nitrogen (N) and phosphorus (P) allowances in line with the Nitrates regulations.
- P allowances are dependent on soil test results. An accurate assessment of the allowance should be calculated within a Nutrient Management Plan based on soil test results. Your local advisor can help with this.
- N allowances are simpler to calculate on most farms based on stocking rate on the grassland area. The N fertiliser allowance for the farm can be estimated using Tables 3 & 4.
Table 3: N allowances per/ha based on grassland stocking rate
| Grassland Stocking Rate (previous year 2023) (kg/ha of org N) | Nitrogen fertiliserallowed (kg/ha) |
| <130 | 114 |
| 131 - 170 | 185 |
| 171 - 210 | 254 |
| >211 | 225 |
Table 4: Estimate fertiliser N allowance on grassland
| Nitrogen fertiliser allowed(kg/ha) (based on Table 3) | (A) | |
| Area of grassland (ha) | (B) | |
| Total fertiliser N allowed (kg) | ( = A x B ) |
Calculations shown are intended as a guide and will vary where farms include tillage crops and where organic manures are imported or exported. Contact your advisor for a definitive estimate of your fertiliser N and P allowance for 2024.
The remaining allowance on the farm can be calculated by comparing the N in fertilisers applied year to date with the overall allowance for the farm. Double check fertilizer allowances with landowners who have land available for 3rd cut – they may have allowance remaining but must adhere to these limits also.
Fertiliser for grass growth in August & September
- Plan fertiliser applications now on grazing paddocks and silage ground to take best advantage of grass growth conditions in the coming months.
- Apply N and P fertiliser within maximum
- There is no restriction on applications of Potassium (K) or Sulphur (S) where required.
- Maximise the growth on grazing paddocks and take a 3rd cut of silage if possible.
Advice for grazing
- Apply N for up to 1.2 kg N/ha/day (56 kg N/ha = 45 units/acre) from 1st Aug to mid-Sept.
- Front load N in August (2/3) and target paddocks with good soil fertility or recently reseeded for best response.
- Reduce rates in swards with good clover content.
Advice for 3rd cut silage
- Close as soon as possible
- Apply up to 75 kg/ha of N & top up with P, K, S or slurry
Book straw as soon as possible
Contact your local advisor or Teagasc advisory office for information, advice and support.