And the kernels will be plump and full

And the kernels will be plump and full

The time of harvesting will vary with the use which is to be made of the oats. If the crop is to be threshed, the harvesting should be done when the kernels have passed out of the milk into the hard dough state. The lower leaves of the stalks will at this time have turned yellow, and the kernels will be plump and full. Do not, however, wait too long, for if you do the grain will shatter and the straw lose in feeding value.

Source: Agriculture for Beginners