Why You Should Get Your Soil Tested with Dairygold

The Health of Our Soils

By Rósín O’Donnell, B.Agr.Sc, Dairygold Agri Business Graduate 0867938408

As an industry we are striving to grow more grass in a sustainable manor. Grass is a cheap, high energy feed stuff. Milk produced from it has enhanced human health benefits and a lower carbon footprint when compared to milk produced from grain.

KEY POINT: The annual cost of soil sampling is roughly 50 cents/acre/year. This is the same cost as 0.5 units/acre of P fertiliser.

The foundation to growing this grass sustainably is good soil fertility. Correcting soil pH is the same as spreading 2.5 bags of CAN/acre/year. It unlocks soil P and K and it leads to a better grass growth response to freshly applied N, P and K.

In the recent past our soil fertility has improved but we have still only 21% of our soils in optimum health.

Dairy soil health
• 21% of soils have optimum pH, P & K
• 59% of soils with a soil pH >6.2 (3% increase)
• 48% of soils at P index 1 & 2 (7% Decrease)
• 41% of soils at K Index 1 & 2 (7% Decrease)

KEY POINT: By soil testing, you can save €23/acre on fertiliser. This is on land with high P and K levels (Index 4) and stocked at 2 dairy cows/ha (0.8cows/acre) *smartfarming.ie

The proportion of soils in index 4 for P is now greater than index 3. Soils are like a vault when it comes to P. The depth of the vault varies with soil type. However, once the ‘vault’ is full, any additional P is at a greater risk of ending up in our watercourses. As you fix your soil pH you should release more of the vaulted P, making it available for growth. If your soils are index 4 you should not be spreading chemical P.

KEY POINT: Soils with P Index 3 will yield more grass DM than a soil in P Index 1. Approximately 0.6t/acre (or 1.5t/ha) This extra grass could be worth approximately €180/acre (assuming all other nutrients are optimum). *smartfarming.ie

Within Dairygold we are dedicated to working with you to improve your soil’s fertility and your farm’s nutrient use efficiency. We have a team of soil samplers available to sample your farm, our analytical service laboratory in Lombardsatown, Co. Cork, is INAB accredited and we have a team of Area Sales Managers that are trained in the nutrient requirements of your crops and that are available to develop a bespoke fertiliser pan for your farm.

For accurate results when taking soil samples:
• Do not sample within 12 weeks of spreading slurry or chemical P
• Take a soil sample every 4 ha /10 ac at a minimum – Sample the area in a W pattern, taking a minimum
of 20 cores per sample area
• Ensure the sample depth is 10cm
• Take different samples from areas that are different soil types, cropping history, slope drainage etc
• Avoid any unusual spots like old fences, ditches, dung or urine patches, drinking troughs etc.