Early and low can pay in wheat
By Wendy Short
FARMERS are increasingly being assured that they can cut seed rates for winter wheat without a subsequent yield loss.
Although growers in the north have been particularly wary about taking the plunge, one Yorks expert says he has proof it can work.
Trial plots on a farm near Pontefract have consistently produced yields of up to 12t/ha using only 80-100 seeds/sq m, he says. But Phillip Marr of Ryehill Farm Service (part of the Masstock Group) stresses that matching the correct variety and sowing date to seed rate is vital to success.
"Farmers have been drilling as many as 500-600 seeds/sq m more out of a fear of slug and crow damage than anything else," says Mr Marr.
"With tight margins, no one can afford the luxury of sowing high seed rates only to find there is little or no gain in yield."
The key to making sure the variety will perform under these conditions is looking at the rate at which it develops, says Mr Marr.
"Everyone is looking for the magic 600 ears/sq m for optimum yield. But low seed rate crops must be sown early to give them time to tiller. That means choosing a slow-maturing variety that will not develop ears too soon. Otherwise the plant will be prone to frost-damage and lodging.
"A fast maturing variety like Soissons is capable of ear development in early November and that could prove a disaster."
Accepting that an early-sown crop will need different management techniques is also essential, says Mr Marr. He suggests starting with a 4-8ha (10-20-acre) block of early-drilled crop to minimise the risks for growers who have always used much higher seed rates. But he is convinced they will soon abandon traditional practice when they see the results.
Solstice would be a good variety to start with and has a good chance of producing high yields, he says.
"An application of autumn insecticide, plus a low dose of autumn fungicide will give a clean crop from day one. It is no use trying to fight disease as late as April. Extra manganese and trace elements are also important for strengthening plant cell walls to get the crop in good condition for winter. *
PHILIP MARRS ADVICE
• Claire and Solstice 80-100 seeds/sq m Aug 20 – Sept 20.
• Option and Deben 200-250 seeds/sq m up to Oct 20.
• Charger and Soissons 300 seeds/sq m no earlier than Oct 20.
Keeping ryegrass in checks a big issue
Ryegrass control is going to be a serious issue for many growers this year, says Mr Marr. "I cannot remember a worse year for ryegrass. Some areas missed by the sprayer are carrying up to 2000 ears/sq m on my trial plots. I am certain target-site and metabolic resistance are to blame."
Mixing old and new chemistry is the best approach to control, he advises, with chlortoluron going on at no less than 1500g/ha.
"Using 5 litres of Tolugan (chlortoluron) and 3 litres of Crystal (flufenecet+pendimethalin) has reduced ear numbers in the trial plots from 2000/sq m to just 3/sq m."
Mr Marr says he has evidence to challenge the efficacy of IPU in the battle against ryegrass. "It seems to act as an antagonist when used in a mix. I think it desensitises the other chemicals and prevents them from doing their job. An application of 3 litres/ha Crystal plus 3 litres/ha IPU was cheap, but it gave such poor results I might as well have left the crop unsprayed."
• Charlie and Alaric Booth, Smeathall Farm, Brotherton, nr Pontefract, W Yorks.
• 186ha w wheat, w barley, oilseed rape, combining peas.
• Soil – coal measure clay to light sandy loam.
• Height – 25m above sea level.
• Rainfall – ave 760mm (30in).
• Wheat yields – up from 5t/ha to 13t/ha in past decade.
Get variety, seed rate and crop management right and you can reap significant rewards, says Philip Marr, technical manager for Ryehill Farm Service. On the left Solstice sown at 80 seeds/sq m on Sept 8, on the right Solstice sown at 450/sq m on Nov 1.