The 'Channeled Scablands' run through the area where gargantuan floods roared through during the last ice age in sudden surges hundreds of feet high when an ice dam broke that let a huge body of water called 'Lake Missoula' in the mountains of Montana suddenly drain - dozens of times. The surges scoured away the dirt from the flows of basalt and ripped huge canyons (called 'coulees' out here) right through the basalt, the largest called 'Grand Coulee', where the namesake damm is located. For a few days the flow was more than 10 times the flows of all the rivers on earth at once and would have literally shook the earth and heard 30 minutes before it arrived. Only now are some - including me - coming to grips with the magnitude of these events and how it shaped the vast 16,000 sq miles of scablands. I'll include a little clip or more of the geological description if you're rain bound and have time.
The Knudsen tractor that levels isn't built anymore as far as I know. I think the running gear was pretty standard stuff. They usually ran the 855 Cummins block.
The cross slot openers, though an Aussie product, I think are on a locally designed and fabricated frame. I neighbor custom drills with one. I usually pull a 'Zero Till' built by the local welding shop for fall planting. I'll try and post a local machine. I think the heaviest is 35' and 60,000 lb loaded. The big Yielders used to be built here. Because our soil has a lot of clay and we don't get summer rain the ground can be very hard in the fall and weight is needed to punch through. And punching through minimizes side draft on the steeper slopes.
We don't usually pay a lot of attention to soil type beyond the obvious. I'm close to the eastern edge of the Palouse against the foothills of what becomes the Bitterroot Mtns further east. There are probably 100 distinct ridges before you come out the other side onto the Plains in Montana. Clay loam is the general description though there is what we loosely call 'forest soil' that is less organic material and lower PH. My ground probably ranges from 5.6-5.8 PH soil. This is all loess soil blown on top of horizontal flows of lava of many sheets that are several thousand ft thick total. Basalt, with some granite peaks that stick out a little higher - like Steptoe Butte. The soil blew in as huge 'dunes' and is several hundred ft thick in places.
ZeroTill drill
http://palousewelding.com/Drill.html
An intro to the formation of the channeled scablands
https://www.youtube.com/watch?v=XvGdASocTn0
