As we move into making corn silage, now is a good time to perform late season cornstalk nitrate tests.

This test available from Penn State will provide results on how well your corn crop utilized nitrogen over the growing season.

Sampling should be done when the plant is between quarter milk line and black layer by following the instructions laid out in Penn State’s Agronomy Fact Sheet 70.

While this test is rudimentary, it does give you an indication of how well — based on weather conditions — your corn crop utilized nitrogen over the growing season.

These types of tests shouldn’t be used alone; coupled with a chlorophyll or Pre-Sidedress Nitrate Test, PSNT, is a good way of ensuring the nitrogen that was applied in the 6-8 leaf stage was mobilized by the plant.

Test results will come back with a low, optimal or excessive indication on nitrogen use.

This information, coupled with summer weather patterns or nutrient application, will allow you to make changes to your program next year. For example, a PSNT could indicate nitrogen need; however, dry conditions could occur after application leading to little plant uptake.

Alternatively, planting corn into a cover crop or a heavy manured field could indicate little nitrogen would be needed at sidedress and the late season test would document the crop’s ability to harvest this organic nitrogen.

Regardless of your nitrogen results, having those silage harvested fields planted to a cover crop will increase the following year’s crop yield.

A recent cover crop study published by No-till Farmer surveyed 400-plus farmers across the Mid-West and the results were pretty typical: Cover crops pay.

Those surveyed found a 1 percent to 2 percent increase in yield following a cover the first year. In the second and subsequent years, the increase continued to rise where those in the fourth year were seeing an 8-bushel increase.

For those who follow a corn/soybean rotation, the University of Nebraska is currently conducting a four-year study on cover crop effects to a whole host of soil properties.

The study recently released some of its biomass results looking at five different types of covers: cereal rye; forage radish; a mix of hairy vetch and winter pea; a mix of rye, radish, vetch and pea; and a mix of rye, radish, vetch, pea, collards, oats and clover.

While the 4- and 7-way mixes yielded the least biomass, the rye and rye mixes performed the best, adding 3,000 to 4,000 pounds of biomass in the spring before termination.

While the overall benefits will be released in a few years, having the ability to add 1.5 to 2 tons of biomass to crop field will improve soil structure, water holding capacity, weed suppression and nutrient cycling significantly.

Andy Gaver is a conservationist with the USDA Natural Resources Conservation Service in Butler County.