MAKE BEST use of pre-emergence weed control choices in spring rape, because options are limited later on, advises Bob Mills of Banks Cargill.
Early weed removal is essential with this crop, as good establishment is the key to success, he says.
“There are a few choices of pre-emergence herbicides for spring rape and they vary tremendously in price.”
Trifluralin is cheapest at 5-6/ha.
“It has the narrowest weed spectrum. Check the label to see whether it needs incorporating, though you will get greater persistence if it is incorporated.”
Cirrus will control cleavers and chickweed, says Mr Mills. “But be aware that you will get a bleaching effect on the crop which can be very noticeable. Use it with caution.”
By far the most expensive pre-emergence treatment is Ramrod. “It”s a very good herbicide, but will cost over 50/ha. It controls grass weeds, shepherd”s purse and cleavers.”
Butisan is a mid-priced alternative. “Depending on the rate, it will cost 20-30/ha. And it can be mixed with trifluralin or Cirrus, to widen the weed spectrum.”
Post-emergence spring rape treatments include Dow Shield for mayweeds and thistles, and off-label Lentagran for cleavers and fat hen. “Both are expensive and Lentagran can be harsh on the crop.”
Graminicides Laser, Falcon and Fusilade can also be used. “Volunteer cereals shouldn”t be an issue in a spring crop, but wild oats may be.”
[box] Arable tables p7 Active ingredients Butisan (metazachlor) Cirrus (clomazone) Dow Shield (clopyralid) Falcon (propaquizafop) Fusilade (fluazifop-P-butyl) Laser (cycloxidim) Lentagran (pyridate) Ramrod (propachlor) ENDS 260 WORDS