8 December 2000

Fine-tune your management to plant count

CROPS drilled at high and low seed rates will soon need specific management to ensure they realise their full yield potential, say independent agronomists.

Although differences in crop density between plots established at 250 seeds/sq m and half that appear minimal, low seed rate plots may need extra nitrogen to boost tillering in the New Year, says Roger Bryan of O & N Management, who is managing one of Novartiss Taking Yields Forward sites at Sittingbourne, Kent.

On light land at Marham, Norfolk, Shane Smith of independent consultancy Farm Vision drilled Malacca at 60, 80, 100 and 120 seeds/sq m using a Stanhay Dart precision drill on Sept 21. So far only the 60 seeds/ sq m area looks thinner, he says.

But such a low population will not withstand many plant losses, he admits. "Plant numbers, disease and other problems will all be evaluated during the next month. We will manage each seed rate according to its individual requirements. If there is lots of septoria, for example, which might threaten plant stand, we may go in with a low rate triazole early next year."

Further north, terrible weather has prevented inputs being applied to farm-saved Riband drilled on Oct 20 at Old Meldrum, near Aberdeen, says consultant Ian Dalley.

Heavy waterlogging in low-lying areas of both the 290 and 350 seeds/sq m plots now threatens plant stand and is preventing leatherjacket and slug treatment.

If heavy rain destroys soil structure and plant stand is thin, an early growth regulator may be used to boost rooting, he says. &#42

Huge variations in plant count will demand very different early spring management, says Shane Smith of Norfolk consultancy Farm Vision.