| Arable
Willingness to change is key to black-grass battle
Admitting there is a problem and being willing to change farm practices accordingly is essential if growers are to get ahead of troublesome black-grass .
S o says Lincolnshire farmer Nick Wade , who after being inspired by a visit to the Hutchinsons National black-grass centre of excellence in 2014 , has introduced several big changes across the 935ha of combinable cropping at Abbey Farm near Sedgebrook .
“ When you work hard every day , it ’ s never easy to be told you ’ re doing something wrong , but sometimes it ’ s what ’ s required .
“ To tackle black-grass effectively , you ’ ve first got to admit there ’ s a problem and be prepared to change what you ’ re doing , which can be hard . Our visit to Brampton was a breath of fresh air and gave us just the motivation needed .” Identifying the problem
Land at Abbey Farm is predominantly Evesham and Denchworth series heavy clay , which until three years ago was mostly down to a simple winter wheat and oilseed rape rotation established early using deep cultivations .
Mr Wade admits the approach was “ ruinous ” for black-grass , and confirmation of RRR resistance to ‘ fop ’ and ‘ dim ’ chemistry , threestar resistance to ALS inhibitors and some pendimethalin resistance , gave added impetus for action .
His visit to Brampton was the catalyst for several changes , with particular focus on reducing cultivation depth and spring cropping . Shallower cultivations
There has been a big move to shallow cultivations where just the top 50-75mm ( 2-3 ”) of soil is moved to create a “ kill zone ” for blackgrass and avoid burying seed for future years or bringing up old seed from deeper in the profile .
Two main machines are used for this ; a 5.5m Simba X-Press or 6m Horsch Terrano fitted with A-shares and press .
Mr Wade has also converted his Simba Freeflow drill to minimise soil movement by replacing the pigtail tines with Weaving Sabre low disturbance tines , reducing the number of coulters and removing the front loosening tines .
The machine now has the same effect as his Weaving Big Disc drill , with a noticeable drop in black-grass emergence post-drilling .
Subsoiling has been reduced , although mole ploughing is used more widely as part of an ongoing drainage improvement programme . This is accompanied by more attention to reducing compaction with low ground pressure machinery and restricting vehicles to tramlines wherever possible . Around a quarter of the farm receives organic manures each year to further improve soil structure . Delayed drilling
The heavy soil has not traditionally lent itself to late drilling or spring cropping , but this has not prevented Mr Wade venturing down this route .
Prior to 2014 , winter wheat was typically sown from September to mid-October , leaving no time for stale seedbeds and increasing reliance on in-crop chemistry .
Autumn drilling is now a month or so later as Mr Wade is keen to establish two black-grass flushes before sowing a crop . He is also much more willing to adapt cropping according to weather , black-grass pressure and soil conditions .
The increased area of spring cropping from 14ha three years ago to 223ha this harvest ( principally spring wheat and beans ) aids later drilling , he says . Spring cropping is the ultimate form of delayed drilling and the later maturity of spring crops helps dry soil longer into the summer which facilitates later drilling of following crops , he says .
“ Spring wheat might be six or seven weeks later to harvest than oilseed rape , so it ’ s taking moisture out of the ground later into the season and is making a real difference .
“ The gross margin can be similar to oilseed rape or first wheat , so there ’ s no panic if we don ’ t get land drilled in the autumn .” Competitive crops
After seeing work at Brampton , Mr Wade has adopted higher seed rates to boost competitiveness of winter and spring-sown crops and compensate for any lower establishment from drilling later .
Winter wheat is sown at 360-450 seeds / m2 , winter barley around 500 / m2 and spring wheat up to 550 / m2 .
He favours spring wheat over hybrid winter barley largely because the cost of hybrid seed makes it prohibitively expensive to sow at such high rates . Spring barley is another option , but gross margins are low for feed barley and spring wheat straw is also easier to chop behind the combine , he notes .
“ We ’ re getting 70-75 % establishment where spring wheat has gone in well , with yields of 3t / acre-plus , so I see a massive future for it , especially if we reduce the oilseed rape area in future .”
Cultural black-grass control is supported with a robust pre-emergence strategy , based around flufenacet , diflufenican and prosulfocarb . Avadex is also applied by a contractor to all first wheats and barley , removing the need for post-em sulfonylurea chemistry .
Mr Wade stresses the long-term effectiveness of black-grass control relies on willingness to change and close cooperation between all parties involved , including his Hutchinsons agronomist Andrew Wright and farm staff .
“ We took our main tractor driver to Brampton and now he ’ s fully behind what we ’ re trying to achieve .”
12 | Farming Monthly | July 2017 www . farmingmonthly . co . uk