When a crop is reaching its harvest date remember to walk the crop frequently. Walk into the crop at least 15-20 rows to get a representative view of crop maturity. Below are a list of things to watch as crop maturity starts to advance.
As maize approaches maturity, plants mobilise water soluble carbohydrates (sugar) from leaves and stalk to lay down starch in the kernels. Starch accumulates first in the outer part of the kernel (closest to the inner husk). As maturity advances, starch fills from the outer part of the kernel, moving inwards towards the centre of the cob. Kernel milk line monitoring provides a handy guide to determine approximate: