Don’t Jump Too Soon With Forage Maize Harvest

The 2010 season seems to have been a successful one when it comes to forage maize.  After a cool start following planting with the ground slow to warm up until the end of April crops then received eight weeks of ideal conditions, for Northern Ireland.  Although July was very dull, with little in the way of unbroken sunshine there was plenty of heat in the ground and crops continued to flourish.  Pollination was generally very good and currently crops are well ahead in terms of maturity compared to the same period last year with plenty of well filled cobs.

Indications from work in Holland would suggest that almost 70 percent of the dry matter yield and 75 percent of the energy in the crop comes from the cob.  Therefore it is imperative that cobs are given time to mature to achieve optimum forage yield and quality.

As crops are looking so well some growers may be tempted to harvest as soon as ground conditions allow.  However, to ensure the optimum feeding value is gained from the crop it is advisable to delay harvest for a number of weeks and at least to mid October.  While the crop remains green the process of converting sugars to starch will continue to take place, improving the feed value of the crop each day that it remains in the ground.  Even after senescence (die back) begins and the crop turns yellow, there is still plenty of opportunity for harvest and allowing the crop to dry out will concentrate the nutrients in the resultant forage.  

Forage maize benefited from early sowing this year, but if it is harvested too early the optimum feed value will not be achieved and the return on investment in plastic mulch will not be realised.

Mark Scott, Dairying Technologist and Michael Graham, Farm Manager assess cob maturity in the crop at Greenmount