Blackgrass was fresh on the minds of those at this year’s Normac cultivations demo near Norwich. Oliver Mark looked at three machines that may help in the fight.
Since relaunching the Dyna-Drive (right) last winter, Bomford has been busy demoing the old favourite across the UK.
A machine designed primarily for shallow-ish cultivations, the Dyna-Drive was first launched in the 1970s and rivals straw harrows and disc cultivators for its combination of high travel speed and low power requirements.
Designed to go straight on to harvest stubbles, the machine will sap about 40hp/m and comes in rigid-frame form no matter which working width you pick from 3-5m. The 3m demo model has a £14,500 asking price.
The first of the two ground-driven rotors is designed to break up the ground, while the second, which travels at three times the speed, smashes the clods. Both of the ferocious-looking rotors travel in the same direction and the crumbler at the back should leave a loose tilth, which means you will want to drill quite soon afterwards to avoid the soil drying out.
A good travel speed is about 12kph and a working depth of about 10cm is common, although a tweak with a 19mm spanner will take it down to 15cm.
Lemken Rubin 9
The Rubin cultivator has been a mainstay of Lemken’s armoury for many years but, despite selling 2,500 units across Europe, UK farmers have traditionally been less keen to dabble with the disc cultivators.
However, Lemken UK boss Mark Ormond reckons blackgrass burdens could force things to change. Rather than completing the tillage job in one pass, he thinks it might be more effective to complete shallow and deep cultivations separately to encourage weed seeds to germinate before they are buried deeper in the soil profile.
Once they are down at 20cm there is no chance of getting near them with Roundup and they will happily sit dormant in the seed bank for years to come.
The ideal working depth of the Rubin is 5-10cm and travelling at 16kph should make sure there is a good mixing effect happening behind the tractor.
The two sets of big, scalloped discs are each followed by a straw harrow to spread any lumps left by the combine. Trailing that is a soil-on-soil roller, which is designed to limit smearing while providing compression similar to that of a cambridge roller to help retain soil moisture for the germinating weed seeds.
A typical-spec, 3m Rubin retails for £16,500.
Straw harrows were the must-have thing for anyone running min-till or direct drilling systems last year, but things have gone a bit quieter since then.
That said, there were still several manufacturers demonstrating their benefits, including Quivogne, with the first public outing for its Beaver straw harrow.
Like the Rubin, it should provide a decent weed chit on lighter land, but takes considerably less pulling. Although a Magnum 315 acted as the tug for the 12m Beaver at the demo, Ben Clowes of Quivogne UK reckons a tractor of 160hp should be capable of doing the job on easier-going land.
Mr Clowes has run several basic trials at his home farm on how best to use the Beaver, including running it twice per field – once to encourage the chit then a second time a week later to wipe out any freshly germinated plants. Alternatively, a good dose of Roundup should deal with weeds and volunteers.
Unlike rival machines, the Beaver has five banks of tines mounted on leaf springs rather than the main frame. This should provide more suspension and take some of the strain out of blatting over harvest stubbles at 20kph.
The 12m version being demoed at Normac has a £38,000 price tag, which keeps it pretty competitive with the rest of the pack.