You must mean, RICE and MAIZE and SOY. We call wheat "corn" in commodities.
I wish I could tell you more about rice: we don't grow rice here.
But we DO grow maize and wheat. We rotate crops: maize, wheat, then fallow.
Maize is dry enough to chip for cattle feed when the kernels are hard to bite and have developed the full dent. The freeze test is to husk an ear of the maize, put it in a polyethylene bag, double seal it, and freeze to -15 degrees F or colder. If it leaves no visible frost, it will be dry enough in two more days. Run the standing stalks through the corn harvester, with the auger set to chip. If you are not using 20-mill silage bags for chipped maize, bag the stripped kernels in 100-lb reinforced paper bags. Store cool and dry.
Soy is a legume crop, so your rows must be exactly 8' on center or you're going to have nightmares with a stuck harvester. Pop enough samples from your field to know that you can strike an average. Two possibilities hit you: green harvest and dry harvest. Your first crop might be better to pick "dry" usually in late July or early August. In cool climates, maybe as late as early September but no longer than that! Later on, you might use the more efficient "green" pick method.
Green harvest. Set the grate for 12" string beans and harvest as usual. The pods will still be intact. If you start getting too many leaves, stems, and rocks, lift the boom but do not go too high as you will miss this low-hanging crop. Set the conveyor for 2" leaves, chop and spread for later tillage. The internal tank fills quickly so keep the catch truck in the row you just cleared. Set the sheller for 1-1/2" beans, run the conveyor slowly, and let the sheller do its job. Then dry slowly using cold air for at least 18 days. Use the heater only to give the dry beans a bit of pre-market polish.
Dry harvest. Set the grate for 10" string beans and harvest as usual. The pods will burst on gathering. The internal tank will take a bit longer to fill with dry soy beans, but you still want to keep the catch truck beside you. No matter what you do, dry soy beans will still have SOME excess water. Vacuum the beans into your silo and run hot air through the column being careful not to exceed 125 degrees F. If necessary, run cold air to equalize the core temperature!
If you can feel humid air at the top vent, you still need to keep the air on and dry them a bit more. Stop forcing air two days AFTER noticeable humidity has disappeared.
