Careful variety selection will get best from maize

Producers should think carefully about which maize varieties they select before considering alternative crops in light of last season’s poor maize growing season.

Kingshay’s managing director Duncan Forbes believes most farmers with a system based around maize are going to be better off sticking with the crop for 2013.

“Although 2012 was an exceptionally poor year for maize, ditching a crop which has performed well over many years on a single poor one means missing out on what is an excellent feed for dairy cows and beef finishers,” he says.

The company’s technical manager Peter Shipton advises growers to consider whether they can grow a better crop of maize through variety choice, management and agronomy before changing cropping.

“Our three-maize variety trial sites revealed some interesting data when they were harvested last year, albeit later than we intended,” he explains.

“Some of the 25 varieties performed well despite the poor growing conditions, whereas others suffered badly and yields were severely compromised.”

According to the Kingshay Maize Report 2013, average yield was about 14.8t DM/ha (6t/acre) on the Somerset and Devon sites. However, the range was 10.4 to 17.5t/ha (4.2 to 7.1t/acre) for different varieties.

On the marginal site in Devon, the average yield was 11.8t DM/ha (4.8t/acre), with a range from 10.6 to 12.6t DM/ha (4.3 to 5.1t/acre). “This shows the difference choosing the best variety for the situation can make,” says Mr Shipton.

Field selection and soil management also play a big part in whether a profitable maize crop is grown. “Following last year’s weather, the soil structure in many fields was damaged by stock and machinery. Long-term waterlogging degrades the soil microbiology, taking time to regenerate after soils have dried,” says Mr Shipton.

“Preparing a good seed-bed will give the best chance of getting a good yield. Ideally, plough and cultivate early to allow the soil to start rebuilding its natural fertility. Deep cultivation will be needed where severe compaction by machinery has occurred, but dig a hole to make sure that it is necessary as sub-soiling will not always be beneficial.”

Mr Forbes reminds producers that grass and other crops also suffered during last year’s wet summer and autumn. And in the short term, there are few spring-sown crops with the potential to fill the silage clamp for next winter instead of maize.

“Fodder beet might appear to match it on growing costs, with the Kingshay Forage Costings Report 2013 calculations showing £117/t of dry matter utilised for both crops, but fodder beet is a late harvested crop, often lifted in November, and the availability of harvesting equipment is likely to make it impractical on many farms,” he says.

There are also issues with learning the agronomy for a different crop to ensure a good yield, suitable storage, cleaning dirty crops and rationing restrictions.

“Forage peas, possibly sown with spring barley, also look like a contender on paper in terms of cost, but dry matter yields are likely to be two-thirds that of a typical maize crop on a good site,” Mr Forbes comments.

Maize fields could be put back into grass, but a reduced first cut this year and losing the benefits of feeding a mixed forage diet next winter will result, he warns.

“One way to keep some of this mixed forage effect without maize would be winter sown wheat for whole-crop. This might be an option worth some consideration in the longer term, particularly where maize is more marginal and should the changing climate make it less reliable.”