Measuring Maturity

“NIAB no longer assess cob ripeness or look at the cob:stover ratios, both of which are key characteristics when measuring maturity,’’ she says. Some varieties identified as very early, based on NIAB data alone, may simply be classed as such as a result of early senescence of the stover,while cobs may remain less mature. In contrast, other early types may have ripe cobs but a stay green nature to their leaves and stem.

While both different types of variety would be classed as being in the same maturity bracket, each one will behave differently in the clamp and provide different feed values in the cow. It is more important to have an indication of total plant performance.

Miss Goult highlights the fact that certain Maturity Class 6 varieties were capable of giving similar higher DM yields to Class 8 types, but with improved feed quality. This is pretty evident from visual inspection of trials, but not always borne out by the results.

“As a result, growers need to look at as many trials as possible – particularly those in their own regions – in order to get a true handle on likely performance,” she says.

Next season, Miss Goult suggests that growers need to be looking at varieties such as Klifton, Kokon and Kadenz. Both the latter two were introduced in 2008; Kadenz is an extremely high yielding variety, while Kokon combines earliness and exceptional ME values.