Slurry: Slurry is one of the key resources farmers have to try and deal with record fertiliser prices this year.

A lot of farmers are sitting it out to see if fertiliser prices will come back but listening to all the industry analysts, this seems unlikely to happen before the middle of the year.

Silage fertiliser is the biggest application of fertiliser drystock farmers will spread any year.

Typically, 100 units of N/acre will be spread for first-cut silage. Cattle slurry generally has a dry matter of 6%. More dilute slurry (2-4 % DM) will have reduced N, P and K values (see Table 1).

Silage crops should receive a large proportion of their N, P and K in the form of slurry in 2022.

Take slurry dry matter into account and make adjustments to application rates to ensure sufficient nutrients are applied to meet crop requirements during the growing season.

The DM% of slurry can be measured on farm with a slurry hydrometer or by sending a sample of agitated slurry for nutrient analysis to a laboratory (N, P, K and DM %).

Typical cattle slurry is 6% DM. It’s important to retain as much nitrogen from the slurry as possible to make it available to the grass plant.

Low-emission slurry spreading (LESS) is central to capturing as much nitrogen as possible. Spreading time is also key. Try to apply as much slurry as possible in spring to maximise nitrogen retention.

Table 2 outlines the different slurry nutrient values.

Spring applications of cattle slurry have up to 50%, higher recovery of N compared to summer applications.

Weather conditions in spring will be more favourable to improving the recovery of N from the slurry. During cool (<13°C), damp, overcast days, N loss through ammonia emissions are lowest.

Spreading 3,000 gallons/slurry/acre in spring on silage fields will deliver 27 units of N, 15 units of P and 96 units of K. Slurry will deliver all your P and K requirements for a first-cut silage crop. You will need to top this up with 2-2.5 bags of CAN/acre or 1.5 bags of urea/acre to deliver the nitrogen that is required.