Producers looking to produce more milk from forage should view grass silage clamps as much more than just a forage store. Instead, open clamps provide an invaluable source of information, which can help improve silage-making next year.
That is the message from Volac’s silage specialist Derek Nelson, who says silage quality and quantity can have a major impact on the financial health of dairy businesses for six months or more, so it is worth reviewing open clamps now to learn lessons for next year.
Five-point question checklist
“It’s only when you get stuck into seeing what’s inside the clamp, and feeding it, that you get a full picture of what you’ve produced and how good it is,” explains Mr Nelson.
“Commit to noting down the good and bad points of the silage now, so you can make any necessary improvement next season. Better still, take photos as well.” To help with the process, Mr Nelson suggests a simple five-point question checklist of the open grass silage clamp: How does it look and what is the temperature? What does it smell like and how does it feel? And how wet or dry is it?
Indicator of silage quality
“Make an honest appraisal of whether the clamp is tidy or whether the face is non-uniform and allowing air to get in,” says Mr Nelson. “Correcting an untidy face can make a big difference to reducing air ingress and surface wastage.”
Another indicator of silage quality is temperature. “If it’s warm, that’s a sign of aerobic spoilage, caused by yeasts and moulds in the presence of air. These effectively burn up the silage’s nutrients. Again, consolidation and clamp sealing may need improving.
Check whether the silage smells sweet or unpleasant. “If it’s the latter then this could be a sign of poor fermentation or the wrong type of fermentation caused by undesirable microbes,” says Mr Nelson. “As with aerobic spoilage, this means some of its feed value could already be lost.”
He says that producers should also check how the silage feels. “If it’s slimy, this can also be due to excess nitrogen at harvest,” he says. “And low sugars and a poor fermentation can also allow undesirable microbes to take hold.”
Silage moisture content
Finally, assess silage moisture content. If it’s wetter or drier than expected, wilting technique may need re-checking, according to Mr Nelson. “Wilting rapidly to between 28% and 32% dry matter is the optimum for both minimising in-field losses and minimising effluent risk in the clamp. If the silage is wetter than the grass put into the clamp, this can be a sign of a slow, inefficient fermentation, since a by-product of slow fermentation is water. Using a proven additive will reduce this risk.”