15 September 1995

Test first to secure best feed

By Jessica Buss

TAKING a grass test before making late cut silage will help guage the ideal date and growth stage at which to harvest the crop to optimise its feed value in the clamp.

The test will also predict what the energy and protein levels in the silage will be, says Mark Harrison of Leics-based Farmlab. As such it is an ideal tool on which to base decisions on which feeds to buy and when to open the clamp.

"Good conditions for grass growth can occur in the autumn," he says. But with low sugars and falling temperatures, leading to low use of nutrients, there will be a less stable fermentation and risk of high ammonia levels.

Testing a pre-cut sample of grass could help reduce any risk of poor fermentation by determining when to cut, what the feed value will be, and which additive to use.

He advises grass samples are taken 7-10 days before expected cutting date. At the lab the sample is tested using NIR analysis. Using the results alongside local weather data, it is possible to assess plant growth stage, its supply of nutrient fertiliser, and how it is reacting to growing conditions.

The result is an indication of potential silage quality and gives the basis for advice on cutting and clamping management, he claims.

Each sample tested at Farmlab costs £18 including post, packing, sample bag and instructions. A sample of 0.5kg of grass is needed. This must be sealed in a plastic bag with the air squeezed out. &#42