Weaver Discussion Group - Managing grazingMonday 25 June 2012
Report of the group meeting held at Henhull Hall in early June to discuss the importance of grazing and how management may be applied to ensure best practice to comply with the NVZ and Water Framework Directive regulation.
The group had the opportunity to walk the paddock system at Henhull Hall which created some excellent debate and discussion.
Importance of Grazed Grass:
Key areas of discussion were:-
The cheapest form of feed at around £30/t DM
Good source of energy & protein
Reduces working & fixed capital e.g. Reduced purchased feed, Bedding costs, Labour (opportunity of cost saved and applied to other farm tasks – fertility, lameness etc.), Less forage storage requirement, Less slurry storage, Reduce machinery costs (fuel, repairs, depreciation)
Maximising Grazed Grass:
There are many areas that need to be considered:-
This depends on the availability of land and location of land in relation to cow accommodation e.g. main road prevents access to grazing then grazed grass may be difficult
Milk contract e.g. are penalties applied to reduced butterfat’s in the spring
How much is to be devoted to conservation e.g. length of winter due to soil type, rainfall, buffer feeding during the summer
System of grazing e.g. paddocks, strip graze, set stock etc.
Track system e.g. concrete sleepers, wood chip (Andrew Penton pointed out that farmers need to be aware of using waste products such as wood chip as these require exemption licences which should be obtained from the EA)
Extended grazing e.g. early turnout and autumn grazing
Grass growth class e.g. soil type and summer rainfall
Nutrient requirements pH, nitrogen, phosphate, potash, sulphur and magnesium are all key elements that require monitoring and amendment as required
The group raised the issue of high input/output verses low input/output dairy systems and which system is the most profitable and environmental efficient. A high input/output system often develops as a result of limited availability of land and high infrastructure costs requiring a business to generate output. This does not mean it is any more profitable than a unit with low output as a low output system usually has low infrastructure cost and good availability of land. The high output system however is generally more environmentally efficient as fewer cows are required.
Nutrient Planning - Grazing:
At Henhull Hall approximately 3,000 gallons per acre of slurry is applied usually in the autumn to allow the store to be emptied. Approximately 240 units of 34.5% bagged N per year is applied to the grazing land in four applications.
It was generally agreed that applications in the autumn is the wrong time to apply slurry as the N content is going to be lost creating increased nitrate loss and the financial benefit of the slurry N lost. If slurry was applied during the grazing season at around 5,000 gallons per acre this could provide around 56 units per acre (70 kg/ha) of available N. This is based on standard analysis and 40% N availability. We discussed in practice that the available N is likely to be much higher particularly on farms in Cheshire with generally good levels of summer rainfall and soils with the ability to retain moisture.
Applications of slurry during the grazing season are best applied by injecting, dribble bar or trailing shoe to reduce inorganic nitrogen input. Applications of slurry by trailing shoe or dribble bar should not cause contamination and therefore rejection provided it is applied before grass starts to regrow following grazing or mowing.
The group did look over an aftermath and discussed nutrient application rates. The field (38 acres) received 3,000 gallons per acre in the autumn followed by 70 units of 34.5% bagged Nitrogen prior to first cut. The group agreed that a second application of slurry could be applied up to 4,400 gallons which would take the field up to the field limit of 250kg N/ha limit assuming standard analysis. This would supply approximately 48 units of N and it was agreed that the field would not require further bagged N although in practice farmers would apply bagged N as insurance!
Andrew Nicholas made a comment that as a group we must prepare nitrogen plans to assess the crops requirement using RB209 to ensure best practice and comply with the regulation. Nitrogen plans require the following assessment:-
- Soil nitrogen supply (SNS)
- Grass growth supply – assessment of summer rainfall and soil type
- Stocking rate
It is also important to adjust Nitrogen applications according to summer rainfall e.g. during dry conditions with little grass growth there could be unused nitrogen.
The group should also go beyond the basic requirement of nitrogen planning by planning and recording phosphate and potash applications.
Regulation & Education:
Philip Percival was concerned whether the policy makers will appreciate the practical issues in meeting the Water Framework Directive such as unusual weather conditions etc.
Unfortunately it comes back to a lack of knowledge transfer or understanding of the Water Framework Directive or NVZ regulation. Farmers and their managers do not have sufficient knowledge of practical and theoretical knowledge of nutrient losses, crop requirements and nutrient recording.
There is a need to simplify computer programs such as Planet to allow quicker and easier crop recommendations, planning and record generation using simple input data sheets. Harvey Hughes Ltd does have manual or computer spread sheets to enable easy and efficient generation of recommendations and records. These are to be distributed if required at the next NVZ/nutrient management discussion group meeting.
It is planned for Andrew Nicholas to contact all group members by the end of the month to arrange an on-farm meeting. This meeting will be to inspect NVZ records to ensure compliance and assist in creating nutrient management plans to include pH, Nitrogen, Phosphate, Potash and Magnesium.
Once all farms have been visited it is planned to hold the final discussion group meeting for which the date and location will be circulated.