What the picture is really there to show you is the milk lines on the corn, where the kernel turns from light yellow to darker yellow. Elliana is holding the corn from our dry land in her left hand and our irrigated corn in her right hand. On the irrigated corn the milk line is about a quarter to half way down the kernel and on the dry land it is almost gone. When it is gone, no amount of water will help you get more bushels when you harvest. You could probably stop watering before that point, but it’s not an exact science.
The milk line is how farmers who irrigate know when they can stop watering their corn. If you’re talking to a farmer raising corn, you might impress them if you ask them towards the end of the season if they have milk lines. They might respond by saying, “My field by the county line is quarter milk line, but my east pivot is three quarter milk line.” You’ll know they’re almost done watering their corn.