During the end of August, the warm and dry weather patterns provided an excellent opportunity for hay making. Some would argue it was the best hay days of the year. Hopefully, most hay producers were able to take advantage of the good hay weather as it becomes quite challenging after Labor Day to harvest dry hay with the days becoming shorter. Corn silage harvest is also under way; corn is drying down, although not very fast, which will make for some excellent feed.

One key indicator of when the optimum time to begin harvest is plant moisture content. The ideal moisture will be determined by what kind of storage structure you will be using. For sealed airtight silos, the ideal range is 60 to 65 percent, for upright silos, 63 to 68 percent; for silage bags 60 to 70 percent, and for trench silos, 65 to 72 percent moisture is the desired range.

Chopping at higher moistures often causes too much acid production (which reduces palatability), DM loss, and seepage. Valuable nutrients will be lost from the crop through seepage, which can also harm the environment.

Ideally, one should test moisture during harvest to stay within the optimum moisture range. If this is not practical, you can monitor moisture by the stage of crop development. A simple method can be used to determine the optimum stage for harvesting your corn silage. When the kernels reach early dent state, a separation can be seen between kernel starch and milk.

Take an ear and snap it in half. You can see the firm starch deposited in the outer part of the kernel while the milk will occupy the base of the kernel. This gives the appearance of a whitish line separating the two areas. The milk line moves down the kernels as the kernels continue to mature. When this line reaches the midpoint, 90 percent of the kernel dry weight has been achieved.

When the milk line reaches the base of the kernel, a black layer forms separating the kernel starch from the cob, the crop is then mature.

When the crop reaches full dent and the milk line first appears, the crop is usually about 70 percent moisture. When the milk line reaches the midpoint, silage yields should be at their maximum and the moisture at 65 percent. When the milk line reaches the base of the kernel, the crop moisture is usually about 60 percent.

By observing the development of the milk line, one can determine optimum harvest time. One limitation of this method is the weather. If you have experienced extremely wet or dry conditions for a few weeks before harvest, the moisture can vary by as much as 5 percent from the predictions given above. There are also wide variations in hybrids, so testing is still important.

Luke Fritz is executive director of the Butler County Farm Service Agency.