24 May 1996

Narrow rows put to the test

DRILLING maize in narrow rows is being put to the test on one East Sussex unit after US research showing it can boost yields by 25%.

David Butler has drilled 36ha (90 acres) of maize at Heaven Farm, Uckfield. It is sown at equal row spacing but instead of the conventional 76cm (30in) widths, it is at 37.5cm (15in) halving the spacing between rows. This differs from the French method of leaving two narrow and one wider row (twin rows) when drilling, he says.

Calypso, Agio and River, were drilled at 130,000 to 145,000/ha (52,000 to 58,000/acre). Within-row spacing was 23 to 25cm (9-10in).

Mr Butler seeks to get more even crop spacing using narrow rows despite the high seed rates and to achieve similar crop maturity. "We used an ordinary drill, but went over the field twice," he says. "This took longer than normal, but saved investing in new equipment."

Drilling in narrow row widths cost £50/ha (£20/acre) extra for seed and labour, but Mr Butler expects growing and harvesting costs to be similar. "If crop yields are an extra 20% over the average of 12-13t an acre fresh weight we will gain an extra 2.5t. That is worth £75 for an investment of £20 an acre." Nitrogen and potash fertiliser were applied as recommended by the Maize Growers Association. Narrow wheels will be used to minimise crop damage when spraying. &#42

Benefits of different row widths and seed rates will be explored at this years National Forage Maize Day. The aim is to see which spacing arrangement achieves the ideal balance between quality and yield. CEDAR and the Maize Growers Association have sown four plots at different row widths and high seed rates – 125,000/ha (50,000/acre) compared with the conventional 98,000/ha (40,000/acre). Seed firm Barenburg is comparing the compact varieties Aviso and Calypso drilled at 125,000/ha (50,000/acre) in equally spaced narrow 37.5cm (15in) or conventional 76cm (30in) rows.