Farmers are being encouraged to utilise pre-cut grass testing to understand  the optimum time  to cut grass for quality silage production.

Lientjie Colahan, sales and technical support at Lallemand Animal Nutrition, says incremental improvements in silage quality make a considerable difference to feeding efficiency and production margins, yet many farmers are missing out on the opportunity to make the best silage possible.

She believes this is often due to overlooking the planning part of the process, with farmers commonly being governed by the calendar rather than actual grass quality.

“Pre-cut grass testing helps determine when the crop is at the optimal point for cutting to achieve quality forage with the best nutritional value,” says Lientjie.

“One of the most important things to observe in pre-cut testing results is the neutral detergent fibre (NDF) content. This is the main gauge of plant maturity, giving the best indication of when grass is ready to cut.

“For example, when we look at the graph below, which shows the average results of pre-cut testing over the last four years, we see that NDF levels can change quickly throughout one season, often in as little as one week,” she notes.

However, Lientjie explains the huge variations between years is the most important thing to note.

Neutral detergent fibre (NDF) content is the main gauge of plant maturity, giving the best indication of when grass is ready to cut (Graph Adapted from Trouw Nutrition GrassWatch 2017-2020)

“This shows why pre-cut testing should be a key component to the annual silage making programme. It allows farmers to accurately establish when to cut based on the quality of the grass in the field, not simply on historic cutting dates or visual assessment,” she says.

“Another very important part of planning is to involve your contractor in the process, as all your efforts to produce top quality forage will amount to nothing if you are unable to work in tandem.”

She suggests keeping them informed about proposed forage plans for the year, with a rough estimate of when you think your first cut will be, and update them as you get pre-cut results in, to make sure everything aligns.

“By regularly testing your crop throughout the season and acting on these results, farmers will be able to set up the foundations to create good quality silage that is high in nutritional value,” says Lientjie.

Lallemand Animal Nutrition has been working alongside farmers to improve forage quality and utilisation for over 25 years and are currently offering free pre-cut grass testing kits. To get yours please scan the QR code or call: 01684 580022.

Pre-cut testing targets

Parameter Target
Sugars (% DM) >15%
Free nitrates <1,000mg/kg
NDF (% DM) 36-42%
DM (%) 18% at mowing

30% for clamping

35-45% for baling

ME MJ/kg DM >12 MJ/kg