Dan Daly Milltown, Co.Kerry Farms free draining soils Increased soil ph from 5.4 in 2012 to 6.0 in 2015

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1 Lime is a soil conditioner that is essential in the soil to obtain the desired ph for the growing crop. Low ph is reflected in poor crop yields and poor use of applied fertilisers In the Kerry Agribusiness catchment area 8 out of every 10 paddocks sampled in the past year were deficient in lime Farmers who spread lime are reporting very positive results on their paddocks John Leahy Athea, Co. Limerick Farms heavy clay & peat soils Increased clay soil ph from 5.5 to 6.2 between 2013 to 2015 across the whole farm Used 120t lime per year on 40ha costing 2,600/yr. This was 10% of the total fertiliser and lime spend in 2015 I ve taken an aggressive approach to liming over the last 3 years, making it a priority area of spending Grass growth has turned around on the farm, grass has a healthier appearance and responds more quickly to N fertiliser. This year I ve noticed improved drainage on the heavier soils on the farm, not increased softening of the soil as some people suggest Dan Daly Milltown, Co.Kerry Farms free draining soils Increased soil ph from 5.4 in 2012 to 6.0 in 2015 Soil tests taken 4 years ago showed my farm needed a lot of lime. It wasn t a priority for me then but I was seeing a lot of paddocks with poor grass growth. Last year I took the plunge and applied 100t to my 42ha milking block, this worked out at one tonne per cow in my herd. I ve seen dramatic improvement in the grass, less dead material in the base, looks healthier and grows faster, especially after nitrogen. Cows are grazing paddocks a lot better this year I ve been able to keep some grass in the cows diet every day since March 10th in this tough spring

2 LIMING ACID SOILS WILL INCREASE: Grass production Release of N (up to 80kgN/ha/yr).... free nitrogen to the pasture Availability of soil P and K Availability of applied N, P and K Soil biological activity The Impact of soil ph on nutrient availability: Very poor response will be achieved from applied fertiliser and slurry at low soil ph. Maintenance Lime Requirement: Lime offtakes each year 150 kgs Chemical N/hectare 300kgs/ha 10,000 litres milk/hectare 30kgs/ha Lime Loss in Drainage (Rainfall impact) kgs/ha Total kgs/ha High rainfall leads to double the lime loss each year compared to low rainfall areas What do you need to apply based on this table? Maintenance lime of 2 tonnes / acre every 5 years in high rain fall areas Findings from a recent Kerry farmer survey The figures below outline the thoughts of a group of farmers asked about liming recently. These relate specifically to the barriers to applying lime and what additional information would be useful about liming.

3 Therefore these suggest that more clarity is required about: Financial consequence of lime use Impact of lime on the application of other fertilisers / slurry Managing paddock availability and taking weather opportunities 1. Financial Consequence - Raising soil ph from 5.5 to 6.3 Year 1 to 3 for every 100 spent you get 300 back Upfront capital cost lime applied years 1 and 3 Year 1 to 9 for every 100 spent you get 600 back Maintenance only cost after year 3 (see Appendix) Applying lime gives a large financial benefit over a number of years and therefore any upfront capital cost should be paid for by medium term financing rather than out of annual cash flow 2. Impact of lime on the application of other fertilisers / slurry Lime and Fertiliser N CAN no problem Urea Urea before lime leave 10 days between applications Lime before Urea avoid urea for a minimum of 3 months Lime and Slurry N consideration Spring Allow slurry to wash into the soil (7 to 10 days) and apply lime N utilisation from slurry in Spring is not affected by lime applied the previous Autumn Avoid applying slurry after lime Summer Summer slurry application has little N impact so interaction irrelevant Autumn Allow slurry to wash into the soil (7 to 10 days) and apply lime P and K consideration No issues at any time of the year

4 3-Managing paddock availability and taking weather opportunities Management Tips 3 Plan lime application as part of your annual fertiliser program 3 Need targeted application based on soil test results 3 If all the farm needs lime apply half recommended amount now and balance in year 3 3 Don t exceed (3t/ac) in a single application 3 Have the lime on-farm in time for spreading opportunity 3 Aim to apply at any time of the year 3 Aim to apply on 20% of the farm each year 3 After silage is an easy time to manage lime application (best after final cut) 3 Towards the end of the first rotation in spring offers a good opportunity as large area with low grass covers 3 Aim for a ph 6.3 to 6.5 on mineral soils & ph 5.5 on peaty soil types 3 On high molybdenum (Mo) soils maintain soil ph <6.2 3 Lime is always required at reseeding with minimum cultivation techniques Busting the Myths around liming My soils will be easier to damage: Some soils tend to poach (break down of soil organic matter) more easily after liming. On these soils apply a reduced rate of lime on a more regular basis. Don t exceed 2 t/ ac per application and apply lime as recommended on soil test report I can t apply Nitrogen or slurry after Lime It is recommended to leave at least 3 months between liming and urea / slurry application to reduce the N loss through volatilization. To overcome this apply urea / slurry first and apply lime 7 to 10 days later Lime can only be applied in the autumn or during reseeding Lime can be applied at any time of the year, including after grazing or after silage harvest Lime is slow to work Lime will start working once it applied and washed into the soil. The finer fractions of the lime will adjust soil ph immediately while the large components will work over 12 to 24 months. For example 35% of the ground limestone is <0.15mm which is the most reactive part of the lime in the year of application There is no fertiliser benefit from lime Maintaining correct soil ph will result in the release of both N and P from soil reserves Lime is harmful to my cows / I can t apply lime as the cows will be grazing the paddock in 21 days Once lime is washed into the soil it poses no risk but slight tainting to the ryegrass leaves during dry conditions after application may cause some slight scouring My farm is in a high Molybdenum area and lime will affect copper uptake by the grass - Once ph is kept under 6.2 there is no problem with Mo induced Cu deficiency. Lime a maximum of 20% of the farm annually to reduce risk I can t spread lime after farm yard manure - Same rule as for slurry. Apply FYM first and lime 7 to 10 days later APPENDIX Financial Analysis: *Assumes each additional t DM worth 161. Year ph Lime applied (t/ha) Extra grass grown (t DM/ha) Cost of lime ( per ha) Financial benefit from additional grass* End year spent 645 returned Every spent on lime 3 returning End year spent 2,577 returned Every spent on lime 6 returning Message : For a relatively small spend you get a large financial return over time. This financial return is in the form of less concentrates required, higher stocking rate capacity and more efficient use of fertiliser and slurry. Once target ph is achieved as little as 10/acre/year will maintain the correct farm lime status.

5 ! PLAN FOR MY FARM Paddock ph Lime When to apply and total amount number / name Required (t) Total tonnes lime

6 List of Ground Limestone Producers 1. Ardfert Quarry, Sackville, Ardfert, Co Kerry Creeves Quarry, Shanagolden, Co Limerick McGrath s O Callaghan s Mills Ltd, Limestone Quarries, Co Clare MJ Cronin, Castleisland, Co Kerry Kenmare Quarries, Cahir, Kenmare, Co Kerry Full details at