RE: Round Up Ready Corn
Roundup Ready means it is resistant to glyphosate (Roundup, Cornerstone, many others) or sulfinosate (Touchdown Total made by Syngenta). It doesn't matter what brand of glyphosate you use it will not hurt the corn. There are different ag formulations made - the only difference in them is the surfactant package they contain for a more sensitive crop (like cotton) and the lbs. of active ingredient they contain. For corn, go with the cheapest generic you can buy - you will NEVER know the difference in formulations. Corn should be sprayed with roundup before 30 inches tall, spraying later will mess up the ear and pollination. The ammonium nitrate can go out at any time but I would get some or all of my nitrogen in the ground to get the corn started. General recs for corn are 1/3 nitrogen at planting and the othe 2/3 at V6 (around 12 inches tall). Hope this helps.