Management is key to high maize yields

Forage options and the costs associated with high-forage diets were two of the main talking points at last week’s National Forage Conference. Sarah Trickett reports

Forage is only cheap when you can grow it well – that was the message delivered by seed merchant, Francis Dunne, at Hartpury College last week.

He explained that while the cost associated with growing maize was estimated at £850/ha (£339/acre), in reality the costs could range from £49.96/t DM to £99.91/t DM depending on yield.

And maize yield isn’t just about the variety being used, it’s about how the crop is grown, he said. “Maize yield is mostly how you grow it; variety will not overcome poor management.”

Season, site, soil structure, sowing date and method, rotation, weed control and soil fertility were just some of the things he listed that would influence yield. But variety was also an important factor to consider due to the influence it would have on yield, he said. “Metabolisable Energy (ME) values on the descriptive list can range by more than 1 ME. Taking this in to account, the best varieties can produce up to £150 more an acre in milk value,” he said.

He also explained that if milled wheat cost £200/t, to increase 18t of 33%DM silage by 0.5 ME with milled wheat it would cost £48. “So it pays to invest in a decent variety and to manage it well,” he said.

But what varieties producers select will depend on how much they are feeding in the diet. Mr Dunne explained that for high maize diets, producers should select varieties with high ME but not very high starch.

“When the maize to grass ratio is less than 65:35% in the ration, producers need to think about harvesting at 32-33%DM, pick a variety for high starch and high digestibility and chop at a length of 9-10mm.”

But when producers are feeding high maize diets Mr Dunne recommends harvesting the crop at 29-30%DM and at a chop length of 15-17mm and picking varieties with high digestibility.

Profing from high forage diets

Are high forage diets more profitable? That was the question posed to delegates by The Farm Consultancy Group’s Max Sealy last week. He explained that all businesses needed to maximise the use of their own materials and to minimise costs of production.

Feed represents 40-50% of all costs with the range in costs varying greatly from farm to farm, according to Mr Sealy. “Costings from Kingshay Dairy Manager found feed costs range from 2.11p/litre to 3.32p/litre for the top 25% and bottom 25% of producers.”

But while on the face of it, moving to a high forage diet can yield an extra 1.77p/lire margin, there are additional costs to consider.

“Additional costs such as reseeding to improve grass quality, extra storage for forage and extra land to grow the forage must be factored in to costings,” he said.

There is also a huge range in forage costs, with grass silage on a three-year ley costing £92/t DM compared to £128/t DM for wheat wholecrop based on 23t/ha.

Cow health and cow type is also something Mr Sealy suggested needed to be factored in when calculating whether high forage diets were more profitable.

“When you are restricting individual cow intake because they are not suited to high forage diets then this could impact on a range of things. For example, there is a relationship between dry matter intake, energy and calving interval.”

Mr Sealy also explained a piece of research that found cows fed a low forage diet saw 5% more lameness. “In a 200-cow herd, a 5% increase in lameness cases equates to £1710 in additional costs of lameness.”

And when taking into account lower purchased feed costs from feeding higher-forage diets, higher-forage variable costs, additional overheads from feeding more forage and herd health, Mr Sealy concluded there could be significant savings from feeding a higher-forage diet.


Want to make the most from your forage this season? If so, then take a look at Farmers Weekly Spring Turnout Masterclass, which details grassland management, online at Alternatively keep up to date with the latest grass growing data with our GrassWatch series in association with EBLEX online at