Maize growers urged to drill before dry-out

8 May 1998




Maize growers urged to drill before dry-out

CULTIVATE maize fields and drill the crop quickly once its dry enough to do so, to conserve soil moisture and ensure a good germination.

Many maize growers have delayed cultivation and drilling because of the wet, and many fields have been waterlogged, says MGA agronomist Simon Draper.

"But when disturbed, the soil will dry quickly and, if it doesnt rain again after drilling, germination will suffer. The priority is to ensure everything can be done in good time before soil dries out." Drilling should be completed by May 15 to avoid delaying harvest.

The site for this years "National Forage Maize Day — including protein crops" at CEDAR on Sep 3, has, for example, some deep tractor wheelings from slurry spreading in less than ideal conditions. It is typical of many maize fields this year, he says. About 1ha (2.5 acres) will be used for variety demonstrations.

This 12.5ha (30-acre) field needs subsoiling before ploughing for maize, says Mr Draper. But subsoiling will add three days to the time the soil is open and being an alluvial loam over gravel it will dry out quickly. It will then take two days to plough using the same tractor, so subsoiling could mean that soil becomes very dry.

If subsoiling cannot begin soon, farm manager James Lamburn will have to consider subsoiling just the worst areas of the field, which will take about one day. But that will reduce crop yields as maize will not grow in any compacted wheelings, warns Mr Draper.

Growers who find it turns dry could try to plough and drill the same day to conserve soil moisture.

"Then you have to decide whether to roll after drilling. When you think it will dry out quickly, roll the seed-bed to preserve moisture. But this will result in less air in the soil which maize roots need to grow," he warns. When its going to turn wet his advice is to leave it.

When maize is not drilled by May 15, seed rates or variety could be changed to improve crop maturity at harvest or bring forward harvest dates to allow grass or cereal drilling, he advises.

When drilling the week after May 15, reduce seed rate by 5%, and 10% in late May. However, he cautions that reducing seed rates or selecting an earlier maturing variety will reduce crop yield. &#42

GOOD GERMINATION

&#8226 Conserve moisture in seed-bed.

&#8226 Sub-soil wheel marked fields where possible.

&#8226 Reduce seed rate for late May drilling.


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