PJ Phelan: Contact ranchers ASAP to secure your precious manure

The challenge is sourcing enough organic fertilizer to ensure compliance with new nitrate regulations, which have brought some welcome specifications but also some additional requirements.

■ All arable land is considered soil P (Phosphorus) Index 4 unless you have a soil test result showing it is at a lower level. This effectively means you cannot import organic fertilizer unless you have soil sample results for blocks of land less than 5 ha (12.4 ac) and assay results less than four years old showing the land is Index 1 -3 for P

■ Either a trailing shoe or trailing hose must be used when spreading manure unless plowing within 24 hours of spreading to reduce gas losses and odor problems.

■ Organic fertilizers must not be applied in buffer zones next to surface water or water intake points. The buffer zone of private wells has been increased to 30m unless there is a hydrology report indicating 15m is appropriate.

■ The prescribed nutrient content of the liquid manure has been reduced to 2.4 kg N (nitrogen) and 0.5 kg P per m3. The organic limit of 170 kg/ha N remains, but you can now apply cattle manure at up to 70 m3/ha (6,300 gal/ac).

Experience and regulations have taught us how much chemical N should be applied after slurry application. Higher recovery rates will make this assessment more critical, with continued focus on soil and weather conditions.

Cold soils need readily available P. Soil biological activity will be low until soil temperatures rise, requiring some chemical P to fuel growth.

Land exposed to waterlogging will lose some N through denitrification, so application timing and soil conditions are critical.

The reduced P concentration in manure allows up to 50 m3/ha on soils with P index 3; 70 m3 on index 2 soils; and 90 m3/ha on Index 1 (but then subject to the N limit of 70 m3/ha).

However, it is still recommended that no more than 50 percent of the P and K (potassium) be applied to index 1 and 2 soils in the form of organic fertilizer.

■ No cultivation or fertilization is permitted within 10 feet (3 m) of any watercourse marked on the 1:5,000 scale OSI maps, with the exception of grass plantings.

■ While the N and P surcharges have been reduced on grassland, the maximum rates for tillage remain largely unchanged.

While the changes are welcomed by most arable farmers, they pose significant challenges for pastoralists operating close to their nutrient limits.

Farmers with high-yielding herds need up to 20 percent more land if they want to keep current stock numbers and are not willing to export manure.

Demand for additional land is already driving up land rental prices, making it unattainable for non-dairy farmers.

The extra land they take is unlikely to be grazed by cows, so it could be sown with tillage and perhaps form the basis of a crop-sharing arrangement with tillers.

From a water quality point of view, it would be more desirable for intensive dairy farmers to export manure to arable farmers. Ideally, the manure would be moved from heavy grassland to farmland with better drainage and land with little or no surface water channels.

The increased risk of nitrate leaching from manure into groundwater is offset by reduced chemical N applications (arable farmers do not take storage risk with excess N); The risk of P losses in surface waters is greatly reduced on soils with better drainage.

In summary, provided farmers respond appropriately, the amended Nitrates Regulation will reduce the risk to surface water and encourage the export of manure from intensive dairy/beef farms to arable farms.

Farmers who practice arable farming should hire dairy/cattle farmers now and receive manure early in the year; That’s better than dairy farmers arriving just before the close season starts looking for a home for excess manure.

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PJ Phelan is a tillage consultant in Tipperary; he is a member of the ACA and the ITCA