Forage maize: the best source of cost effective starch
19 September 2007 | Mark Britton
New Descriptive List leader, NK Bull offers yield plus quality - top dry matter yield, top digestibility and the highest starch content in its maturity group.
Forage maize offers a very high energy yield per ha and at 60% of the cost of wheat, huge savings as a source of starch within beef and dairy diets, according to NK’s Nigel Padbury. Furthermore, new varieties such as NK Bull added to the recently published NIAB Descriptive List of Forage Maize 2008, with a top dry matter yield, top digestibility and the highest starch content in its maturity group, can allow farmers to make improvements of 10% or more to their crop’s productivity.
"At first glance at the new Descriptive List, farmers are faced with a potentially bewildering choice of over 60 first choice varieties in the Early and Medium Early categories," says Mr Padbury. "Choosing the right variety is often a balancing act between opposing demands of high digestible yield and high starch, but by deciding from the outset which of these characters is most important to them growers can prioritise the List; short listing only those that make the grade for the characters needed and ignoring those that don’t.
"Where maize is intended to supplement what is principally a grass based diet then starch yield should be the priority, and varieties such as Avenir with a 35.7% starch content will come to the fore. For those looking at maize as their primary source of forage then maximizing DM yield and digestibility is a must. Here the new variety NK Bull comes into its own," he explained. "NK Bull has the highest available DM yield of 111% of controls at 18.8tDM/ha with the best score for digestibility at 11.5 MJ/kg DM, it delivers an unbeaten 216,000MJ/ha and a very respectable 32.8% starch content."
Keenan Rumans consultant nutritionist, Hefin Richards commented: "Maize offers a huge opportunity to grow energy on the farm, at a time when wheat prices continue to escalate to unprecedented levels. Therefore growers should exploit the latest technology in terms of plant breeding, crop management and nutrition if they are to maximise returns.
"Feeding a mixture of forages enables livestock producers to secure a degree of insurance against a single poor crop, and provided the ration is correctly balanced and structured, mixed forage diets will stimulate intakes and rumen function."
Increasing forage intakes and utilisation allows for either higher production at a given level of concentrate feeding, or a constant level of production with lower levels of concentrate, he said. "This is an issue which mattered little when grain was available at under £80/t, however it has become critical as grain prices, along with other energy feeds, surge towards £200/t. Feed wheat processed at £190/t equates to around £350/t of starch available. In comparison, a 38t/ha freshweight crop of maize at 30% DM and 30% starch produces 3.4t/ha starch which could replace £1,200 worth of wheat starch within the diet and will typically have cost £750/ha to produce with the added bonus of energy from digestible fibre and the bulk of forage available.
"Having more maize available for higher inclusion rates or for all year round feeding is a must for many producers, and this can be achieved by firstly maximising the output of the current area, he said. "Variety selection can achieve an additional 10% or more increase in yield, and improved agronomy and management could achieve similar gains on many farms. This allied with an increase in maize area could have a massive impact on the cost per tonne of maize produced and the quantity available."
Mr Padbury added: "Through careful maize variety selection together with good agronomy there is an opportunity to increase overall yields per hectare thereby reducing the cost per tonne, and the additional maize gained through these higher yields will allow for high inclusion rates in forage diets or reduced concentrate costs."
To find out more about NK Bull, click here (opens new window).
To find out more about Avenir, click here (opens new window).
