Expect Variable Quality In The Clamp Unless We Get An Indian Summer Says Maize Specialist

That’s the advice of KWS UK maize product development co-ordinator, John Burgess, who blames early season stress and the poor summer for the harvest delay.

“Establishment was very variable and crops were slow to get going,” he says.  “Those drilled late – even into the second week of May in some cases – have been late to tassel and are a fortnight behind normal.

”This early stress has resulted in double cobbing in many cases, however this in itself should not adversely affect silage quality.  Seedbed quality and low soil temperature delayed drilling across many sites.

“In contrast, while some crops sown in the last week of April are bulking up quite well, even these will be a week behind normal to mature because of low heat units and delayed tasselling.” 

“So unless we now get a good month of hot, even temperatures to finish the crop, silage and resulting clamp feed out is likely to be an issue this season.”

Mr Burgess advises farmers to pay particular attention to cob ripeness when assessing dry matters in the run up to harvest. 

“There will be marked differences between varieties this year and while this will help you pick out consistent types that can cope with a poor season.

“You should be looking for good cob maturity with grain at the milk line and avoid cutting too early unless crops are under heavy disease threat,” he says.

He points out that KWS actively selects for varieties with good early vigour and an ability to produce early cobs on green stover.  This early grain development is important in a season such as this, ensuring high starch contents as well as good whole plant digestibility.

“Early cob ripeness will enable the crop to deliver the desired maturity at harvest, and in the case of many early varieties, the plant will dry down prematurely, giving a false impression of maturity, and delivering poor ‘D’ values.

“KWS therefore selects types with an even level of green stover and cob ripeness to maximise silage feed value as well as yield.  In addition, these types also offer little variation from season to season and, on farm, produce consistently stable high yields with good feed quality.

Mr Burgess says that growers should take the opportunity to visit as many trials as possible to judge this for themselves.  “With harvest a good month away, it’s pretty evident in the field. 

“Look for differences in tasselling and also cob ripeness,” he says.  “Varieties such as Kadenz, Kokon and Klifton are standing out as particularly forward in trials across the UK.

“And, while NIAB baseline yields suggest these types may not be table-topping, they can clearly cope with seasonally low temperatures across a wide range of sites without vast swings in yield or feed-ability.

“Kadenz is much further forward in terms of cob ripeness than its NIAB maturity rating of 7 suggests.  It’s a big plant and will produce high yields as well this year,” he says.

“While similarly early to cob, Kokon will produce a higher energy silage helping farmers maximise milk potential.  It’s a good choice where DM intake is limiting herd performance.”

For the future, coded variety KXA7006 – due to be test launched this spring - looks very promising.  “KXA7006 is one of the earliest types every seen in the UK.  It’s short, compact and a potential Class 10 or even 11 maturity type, so will be very useful in marginal sites where, because it is so early, it will provide security in difficult seasons such as this.”

When it comes to selecting varieties Mr Burgess says that growers should heed the lessons learned this season.  “When looking at trials, consider ME values as more important than DM performance and ask yourself if the variety really has the earliness characteristics needed to cope with years like this.”