Forage and Grain Crops 
Agronomy 105's Weed ID
Common oats
Oats have a panicle type of inflorescence and is used primarily for livestock feed and to a small extent for human consumption. 
Oats are also used as a companion crop and small seeded pasture legumes can be seeded directly into a field of oats.  The purpose of this is to give the farmer some monetary return from his land during the year of forage crop establishment.  Oats are grown mostly in the northern part of the United States and the spring types are the most predominant. 
The seeds of oats thresh with the hulls attached.  It is common to find two distinct sizes of oat kernels because each full-sized kernel in the panicle will have smaller kernel growing right beside it.