Finding a way to solve maize puzzle at harvest time
Early indications from NIRS analysis by Wynnstay suggest maize quality in the clamp may be affected by the variable conditions throughout the growing season.
Analysis of over 30 samples taken in mid-September, from across the Midlands and South Wales, suggest dry matter, starch and metabolisable energy may be lower than previous years.
There’s a lot of maize around, however many crops were drilled into challenging soil conditions, which slowed establishment. This appears to have had an impact on the potential yield and quality of some crops.
The Wynnstay analysis results, which included 11 varieties, highlighted a range in overall quality, and provided a good indication for the general trend of maize crops across the region.
From the 32 samples, DM content ranged from 17.6 per cent to 33.1 per cent. The target dry matter at which to harvest maize is around 32 per cent, and a quarter of the samples tested achieved dry matters of 30 per cent or higher.
This means that harvest will be slightly later this year compared to the previous two seasons, and the challenge of the recent excess rainfall may well delay harvest further.
This really does emphasise the importance of growing an early variety and ensuring rapid establishment, because at the time of sowing we have no idea whether or not an early harvest will be achieved.
To secure the best quality crop possible, we must ensure we’re harvesting at the correct maturity, and not simply chopping because others in the area have started. It’s also very important not to leave the crop out in the field once it has reached the correct stage for harvest.
There are a couple of simple ways in which growers can see if cobs are mature.
To visually check the cob, simply snap it in half, break off a kernel and squeeze it. If milky liquid squirts from the kernel, or if any liquid remains at all, the crop needs more time to ripen. If there’s no "juice" in the kernel, and the starch is firm, it’s ready.
In addition, take into account how green the stem and leaves of the maize are. The DM of the cob has a major influence over the total crop DM, and it’s better to harvest while the crop is still green, and before the leaves begin to senesce and die.
If the cob is not quite ready and the stover is still extremely green, it will be better to wait for a little while, while still keeping an eye on the weather.
Generally, cobs are a good size and should be mature at harvest, giving decent starch yields. Overall, DM yields probably won’t break any records this year, but they should still be quite acceptable So, if producers pay close attention to harvesting the crop as soon as it’s ready, and balance the forage correctly in diets, maize will again be a great asset in rations this winter.
Dr Simon Pope is Wynnstay crop protection manager.
