This region has extremely heavy, dense black soil types, described as ‘self-mulching, cracking clay’. Growing in heavy floodplains, Paul says it is ‘very poor draining, and they have issues with moisture penetration, and compacted soil’. Prevention of cracking and preservation of structure is realized through high frequency irrigation of the farm.
The 4AG Supergrubber has helped him rip at depths he couldnt get with his previous straight shank ripper. ‘Our current ripper is 9mtrs wide. So while we have gone back to a third of this width, we are getting nearly three times the depth at 42cm, whereas previously we could only reach 15cm, this has got to be better for root development of our crops’. ‘The straight shanks on the old ripper were also hungry on horsepower, compared with the progressive leg design of the Supergrubber’.
Paul pointed out to 4AGs product specialist the evidence of ‘poor root development’ in the residue of the previous cotton crop. ‘You can see here the tap root clearly goes sideways at a certain depth with a noticeable kink in it, this means it has come under pressure when faced with a hard layer to try and break through’.
Compaction is a problem Paul is very mindful of, with the cropping operation running controlled traffic farming. ‘With wheel centres extended and the same on all tractors, we are avoiding compaction across 70% of our fields’. ‘Our big John Deere cotton harvester also has a maximum weight of 38 tons when fully loaded, so you can imagine the compaction this causes as well’
Paul says one of the most impressive features of the 4AG chisel plough is the aggressive double spiked roller at the rear. ‘We have done a bit of development work where we have been ripping in the bottom of drains, we wouldn’t normally work ground that is this wet. The dirt was coming off the seven legs like streams of thick cheese, and the double spike rollers never blocked once, but just smashed them into good size particles and firmed everything down’
Paul is looking forward to using the Supergrubber more in coming years, and the improvements in soil structure and organic activity ripping to this depth will bring.