295ha of first wheat following oilseed rape was direct drilled with a band sowing drill and a tine drill in 2015, the first autumn of acquisition of the Wellingborough farm. 97ha was lost to slugs, this was re-drilled and again written off due to relentless slug pressure. Losses including labour, machinery, seed, pre emergence herbicide and 3 applications of slug pellets were in the region of £200/ha in addition to the reduced output from the spring crops which followed. [spring barley and peas were also full of black grass]
Year 2 where all first wheat was following pulses and slug pressure was less than year 1, lost crop due to slugs and blackgrass pressure still amounted to 22ha. [and very poor yields crops that were covered in blackheads but we couldn’t afford to write them off]
Year 3, autumn 2017 when just one 4m Triton drill was used no wheat crop was lost to slug. This was due to improved seed soil contact, consolidation without compaction from the closing tines restricting the slugs ability to traverse the seed slot. Emergence rate was noticeably faster even in the delayed drilling regime. A saving was made on slug pellet applications and blackgrass pressure was noticeably reduced due to less soil disturbance through the profile. [Yield av went up to 3.5t/ac milling wheat in a drought and some black grass]
[2018 autumn, whole 1050 acres drilled with one 6m Triton between Oct 25th and Nov 10th. No spring crops in rotation. All crops clear of black grass at present but early days]
[words in brackets – Simon Chaplin – Triton Seed Drills]
Jerry Dee National Crop Protection Company