a process for the ammoniation of straw and other plant materials containing lignocellulose with a dry matter content of at least 60 %, utilizing anhydrous ammonia , preferably in liquid form . the plant material is covered by a gas impervious material and ammonia is added in excess of the amount needed for optimal irreversible nitrogen binding , preferably from 20 - 35 kg nh 3 / ton dry matter , without application of external heat and pressure . the ammonia impregnated material is left at ambient temperature for at least 10 days , whereafter it is vented and ready for use . the preferred use of the ammoniated straw is as an animal feed .