Walk maize crops to assess forage quality

07 Aug 2018

An early maize harvest could catch producers out unless they start monitoring crops soon, according to Limagrain’s Tim Richmond. 

With maize harvest looking to be at least two weeks earlier in many parts of the country, he says that it is important to focus on harvesting maize in optimum conditions.

Early harvest

Mr Richmond says there are two main reasons why the maize harvest should be significantly earlier this year. The first is the season where, due to the prolonged drought, crops are generally two weeks ahead. “The hot weather means the accumulated Ontario Heat Units are already high, meaning crops are maturing quickly. We have seen early tasselling and crops drying down quicker.

“The second reason is that to help reduce the problems created by the cold and wet spring, as well as lower soil temperatures and delayed drilling, we saw a swing from later maturing varieties to earlier maturing options. 

Switching varieties

“Early varieties will typically mature two weeks ahead of later maturing varieties, irrespective of the season. Where producers switched varieties, they could be looking at harvesting four weeks earlier than in 2017.

“Correct timing of harvest is essential to ensure the best yield of high quality maize silage, so I recommend walking crops from late August to assess maturity.

Optimum crop

“The target range for an optimum crop is between 32% and 35% dry matter. This maximises the dry matter yield and starch content while, at the same time, also maintaining better digestibility in the vegetative part of the plant. This typically contains 50% of the energy. 

“At dry matter levels higher than this, palatability and intakes can be reduced. Digestibility will also be compromised and the crop may prove difficult to consolidate, increasing the risk of aerobic spoilage.” 

Grain consistency

He says that producers should look to harvest when no juice emerges when the stem is twisted, and when the leaves level with the cob are just beginning to turn brown.  “The grains at the top of the cob should be like soft cheese and those at the bottom should be like hard cheese. The grains in the middle should be soft enough to leave the imprint of a thumbnail,” he explains.

“As well as regularly walking and assessing the crop, it is vital to talk to your contractor so they are aware of likely harvesting dates. By reacting to the season, you will be able to ensure the best quality forage.”