Practicalities of Nutrient Redistribution

Alan Morrow & George Mathers

Acknowledgement Dr John Bailey & Martin Mulholland

Potential for redistributing phosphorus in NI

Phosphorus is much more than a by-product of the livestock sector

Appropriate redistribution of phosphorus is in keeping with sustainable land management

Nutrient redistribution has been used to solve water quality problems in the past

Limitation to land bank

Land suitability

Not all land with an apparent P deficit is a suitable candidate for receiving nutrients from another farm

Land managed under agri-environment agreement (approx. 385,000 ha - December 2013)

• Land with no slurry or manure spreading restrictions above those required under NAP – (56%) – mostly improved grassland

• Land on which spreading is permitted with input restrictions in addition to NAP - (16%) – eg. semi-improved grassland

• Land on which spreading of slurry or poultry is not permitted - ha (6%) – semi-natural and species rich grassland

• Land on which spreading of farmyard manure, slurry and poultry litter is not permitted – (22%) – eg. heather moorland

Land suitability

Sensitive habitats outside agri-environment agreement?

o Designated sites – ASSI, SPA, SAC

o Environmental Impact Assessment (Agriculture) Regulations (Northern Ireland) 2007

o Possible to quantify suitable land

Land availability

Many landowners may not consider importing slurry on to the farm:

o self sufficient in P with on-farm livestock manure

o content with extensive low input system

o fear of introducing disease to the farm – current guidance to

reduce the risk of introducing TB into the herd

Land availability is much more difficult to predict than land suitability

Unsuitable land

Suitable land?Is it available?

Application of manures & Nitrates

At presento Livestock manures can be applied without the need to show a

crop need for phosphate,

• If this flexibility is lost it would very difficult to find sufficient suitable land & there would be added cost.

From 1 Jan 2017 high P manures can only be applied if there is a crop requirement,

• Affects some poultry manures & a few others,

• AFBI has started a research project on poultry manures will provide updated manure analyses which is anticipated will reflect the reduced P in feed and may take them out of the high P manure category.

Barriers to redistribution

Nitrates Regulationso Need to calculate N Loading

• Exporter and importero Need to calculate crop requirement for P

• Arable importer & possibly grass importer if applying P fertiliser

o Need to keep records of manure exports/imports

• Exporter & importero Need to submit manure export records to NIEA

• Exportero Derogated farms need to check P Balance

• Exporter

Barriers to redistribution

Distance

o No surprise that fields close to farmyard are over supplied and fields further away are under supplied.

Conacre 31% of landWhy invest for long term if tenure is uncertain

Cattle slurryDM %

Value of load (2000 gal) (£)Breakeven distance slurry store

to field (miles)

P & K Index 1 P & K Index 3 P & K Index 1 P & K Index 3

2 18.0 5.3 5.0 0.8

6 26.0 6.7 7.7 1.2

10 32.6 6.7 9.9 1.2

Help available for farmers to make better use of manures

Farm Nutrient Calculatorso Nitrogen Loading Calculatoro Manure Storage Calculatoro Crop Nutrient Calculatoro N Max for Grasso Phosphorus Balance Calculator

7000 users

Available at DARD Online Services with the same access as APHIS online.

Soil Analysis

To assess pH, P and K levels

Whyo To correct low pH,o To improve soil fertility and crop yields,o To avoid applying nutrients if P & K indices are high (cost and

environmental benefits),o To allow manures to be targeted to low index soils.

Soil Analysis

Optimum values to produce high yielding crops on well drained improved land are:

o pH Over 6.0 – 6.5

o P index 2 (index 1 for extensive grassland)

o K index 2-

Soil analysis results

For N. Ireland soils

o pH 60% of soils are below optimum (pH< 6.0)

o P 28% of soils are below optimum (index 0 & 1)

43%of soils are above optimum (index 3 and above)

o K 40% of soils are below optimum (index 0 & 1)

Soil analysis

New soil analysis contract between DARD and Lancrop Laboratories which is:

o 24% cheaper - £7.00 + vat per sample,o Less than 20p/acre/year,o Has improved reports with colour coding and nutrient

recommendations.

New report

Manure processing

Local example of slurry separation, Equipment used – centrifuge slurry separator, Cost approx. £115K, The solid portion has most of the P, Advantage of separating P for this pig farm:

o The solid (high P) portion can be exported to arable farms at less cost,

o The liquid portion with high N can be exported to nearby grassland farms.

Manure dry matter app.

To determine slurry dry matter and nutrient content

o Based on the correlation between the diameter of a 500ml pool

of slurry and dry matter,

o Produces a very accurate estimation of dry matter and

subsequently nutrient content.

o Leading to more accurate nutrient management plans.

Grass yield measurement as a driver for nutrient management

Arable farmers can monitor fertiliser inputs against crop yield and

quality,

Grassland farmers do not have grass yield information on tonnage

and dry matter.

Silage yield measurement and on the go dry matter is now an

option offered by the leading harvester manufacturers.

CAFRE is evaluating the Agri-Net grass budgeting programme.

Collation of grass budgeting data using the AgriNet programme shows yield range of 6.4 – 12.0 t grass DM/ha on CAFRE dairy paddocks

Conclusion

Phosphorus is a finite and valuable resource which must be used efficiently,

Not all low P soils are suitable or available for phosphorus redistribution, Landowner approach to biosecurity may act as a barrier to redistribution, More stringent manure application regs. would add significant

difficulty and cost to industry, Nitrates regs., distance and conacre are barriers to nutrient redistribution,

Conclusion continued

Online tools are available to help farmers move the right amount of manure to the right place.

Soil analysis and nutrient management has potential to help farmers make full use of manures to improve soil fertility and raise crop yields,

Manure processing can assist nutrient redistribution – further work is needed to assess the range of technologies,

New technology to assess grass yields could stimulate increased interest in soils and nutrient management