With the dry weather and late planted corn in some areas of the country there may be concerns of high nitrate levels in silage. This can be in grass silage also. Be sure to take a nitrate test to check the levels in your crop. Cut entire plant at whatever height you are going to harvest it. Do this with at least 10 stalks, cut the entire plant into segments, mix together well and send the lab a gallon of the material. See our library article "Excess Nitrates in Drought Stress Corn" for directions and tables.