The conditions that many arable farmers have had to contend with this autumn and winter have been challenging, with less than half the winter wheat planned actually in the ground. The weather has been described as unprecedented at the time of winter wheat plantings. But it isn’t all negative as the decrease in winter cropping will lead to an inevitable increase in spring cropping and this can allow opportunities to reduce black-grass across the farm. The industry Early Bird Survey, conducted by AHDB and Andersons, predicts the spring barley area to go up 28% to 915,000 hectares, the biggest area since 1988. The area of spring wheat is expected to be up too, but the actual area predicted will be in the next phase of the survey. All experts agree spring wheat area will be up significantly.
Growers are aware that moving to spring cropping is an important cultural method of control of black-grass, as this weed predominantly germinates in the autumn. “However this year,” says Barrie Hunt, technical manager for Gowan, “many growers have been forced into expanding their spring cropping and black-grass emergence has been impacted by the very wet conditions. This is because autumn germination can be delayed by induced dormancy in wet soil, with weeds germinating in the spring when the soil dries out.” He goes on to explain that this has been confirmed by the weed expert John Cussans, NIAB, who says “Wet soils create anaerobic soil conditions and this environment can induce dormancy in black-grass. We do not know how much of the autumn population is affected but there is no room for complacency.”
Mr Hunt says that “typically we see 15-20% black-grass germinating in the spring, but this spring we are likely to see levels well above this. Luckily we have the well proven herbicide Avadex to use this spring. Avadex 15G Excel and Avadex Factor are both recommended in spring barley and spring linseed and the Granules in spring wheat.”
“And what is very important is that both Avadex products, granules and liquid, are recommended at their full black-grass dose rate, unlike most other pre-emergence herbicides many of which can only deliver 50% of their full black-grass rates in spring crops. So with Avadex you are much more likely to get a positive result.”
“Avadex Excel 15G and Avadex Factor in spring barley also have a wider application window, being recommended ahead of drilling as well as at the classic post-drilling pre-emergence slot, allowing more time to get on. Performance is the same pre or post drilling.”
And Mr Hunt says, “Don’t forget that tri-allate was originally introduced as a wild-oat herbicide and excellent control is still being delivered over 50 years later! Avadex products also give a useful contribution to broad-leaved weed control, including common field speedwell, red dead-nettle, forget-me-not, poppy, mayweed, cleavers, pansy, chickweed and charlock. They provide a useful start to reducing weed pressure during crop establishment when the crop is sensitive to competition.”
Points to consider when applying Avadex this spring
- There is likely to be more black-grass germinating this spring.
- Avadex Excel 15G and Avadex Factor are recommended in spring barley and spring linseed, the areas of which are all predicted to be up significantly this spring. The granules are also recommended in spring wheat, but not the liquid formulation. Use of both products in linseed is via an EAMU.
- Avadex Excel 15G and Avadex Factor have a wider spray window in spring barley, pre-drilling and post drilling pre-emergence.
- Avadex Excel 15G and Avadex Factor control black-grass, wild-oats and give a useful start to controlling broad leaved weeds including common field speedwell, red dead-nettle, forget-me-not, poppy, mayweed, cleavers, pansy, chickweed and charlock.
- Always apply the Avadex product at their recommended dose rate of 15 kg/hectare for the Excel 15G granules and 3.6 l/ha for the liquid, Avadex Factor. Applying 100% of the black-grass dose rate will mean better opportunity for good weed control levels. Most other pre-emergence herbicides are not recommended at their 100% rate in the spring.
- If applying Avadex granules, calibrate your applicator, which should include a patternation test, before use. Also regularly check applicator pipe work and deflector plates, ensure deflector plates are clean and at the right angle to maintain an even spread pattern across the boom.
“With Avadex we have the opportunity to get good weed control including that of black-grass and wild-oats in spring crops, turning a negative situation into a more positive one,” Mr Hunt says.
