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What to do in case of hail damage in maize?
During the growing season, crops such as maize can be affected by hailstorms. The question is whether the maize crop should be considered lost after hail, or whether there is still any chance of recovery.
With moderate damage due to hail, the foliar apparatus is damaged in the form of perforated or torn leaves.
Moderate hail damage
If the growing point (heart of the plant) is not damaged, regrowth/continued growth will simply take place and there is no reason for drastic measures such as the destruction of the remaining crop. However, there is a greater chance of, for example, an infestation with foliar fungi in the further course of the season.
Heavy hail damage
In case of severe hail damage, the leaf apparatus is often completely destroyed and knocked off the stem. The question is also whether the plume and spadix formation are damaged. Although this is quite difficult, patience should be exercised and regrowth/growth not assessed until a few days after the hailstorm. If, after assessment, there is some recovery and the plumage and spadix formation are not or hardly damaged, the advice is to leave the crop standing. Unfortunately, a lower yield and a greater risk of leaf fungal attack must be taken into account.
Devastating hail damage
The maize plant was completely destroyed in a devastating hailstorm. The leaves have been knocked off the stem and the stems are broken. Such corn, or what is left of it, must be considered lost.
At this point in the growing season (late June/early July), overseeding/reseeding with maize seed on such plots no longer makes sense. Even with the very earliest maize varieties it is very doubtful whether an acceptable maturity is achieved. Maize that is still being sown is about sixty growing days behind on maize that was sown on time (around 1 May). That is one third of the normal growing season (+/- 160 growing days for silage maize). At the same time, June 21 is behind us as the longest day. A warm August month and an excellent late summer in September can compensate for a moderate growth retardation to some extent, but sowing two months later than usual cannot be compensated. Given the photoperiodic response of maize, later sowing should take into account a longer crop, but also a much delayed flowering and a thinner and therefore weaker stem. The grain setting and cob formation will then start (too) late. And since the date around October 15 equates to the end of net photosynthesis (net dry matter production increase), there isn't much room to get a filled flask. The dry matter and starch yield is then low. In addition, due to low dry matter percentages at harvest, there will be considerable losses of press juice during the silage period.
Opting for an alternative to hail-ravaged maize fields
Fields of maize that are destroyed by hail after mid-June are best sown with a crop that can provide some yield and quality for the remainder of the growing season. An option, for example, is Italian ryegrass. To do this, flail off the remaining maize crop and then plow it under in combination with a furrow packer to create a good seed bed, prevent the seed bed from drying out and reduce the weed pressure. If there is room on the farm for the following crop to deliver sufficient yield and quality, it is desirable to add a small starting dose with organic fertilizer. An important point of attention is the possible effect on this crop of the crop protection products used in the maize (soil herbicides).
Weather insurance against crop damage
Possibly as a result of climate change, more extreme weather conditions during the growing season should be taken into account. As is much more common in arable farming, it is worth seriously considering taking out (broad) crop insurance against extremities such as hail. In this way, the financial damage caused by a crop failure may be partially or completely covered.
Consult your KWS advisor in the event of alleged damage
For expert advice regarding your own specific situation (assessment of damage and possible follow-up measures), consult your KWS advisor.
