It's been busy. We're a little late because of the cold wet spring, as well as having several key pieces of equipment broken. At this point we're making due.
We've figured out its the purple top turnip that was part of the cover crop I seeded last August. The most likely explanation is that they somehow overwintered.
Another possibility is this:The mix I put in included 2 lb/acre of both radish and turnip which I put in the small grass seed box of my 750 Deere drill. The other, larger seeds - leftover wheat, winter peas, some leftover sorghum sudan, sunflowers - went in the large/main drill seed box. The larger seeds were planted 2" deep, the brassicas dropped on the surface and pressed in by the gauge wheels on the drill. I changed this after seeing that the turnips weren't dropping down the seed tubes from the grass seed box because at such a low seeding rate the seed cups on the grass seed box were almost shut and prevented the slightly larger seed from flowing. I sifted out the turnips from the radish and put the turnip seeds into the larger seed box, where, along with the other varieties, they would be drilled at 2" deep. I didn't think too much of the fact that I didn't see many turnips. I think what happened is they were so deep they never got a chance to germinate and so sat dormant for the winter, coming up in the spring. **It's just a theory, but I think this is a useful way to get an over winter/early spring cover established after wheat/before corn or soybeans. **
It's discing down nicely - Krause 8200 disc.
I made a video playlist about the overwintering red top turnips - here.