Oats are cereal grains whose origin can be traced back to about 2000 B.C. in the Middle East, particularly the areas surrounding the Mediterranean Sea. Some of the first evidence of oats were found in Egypt and parts of Switzerland.
There are several species of oats, but only two are of significant commercial importance. The avena sativa species accounts for 75% of world production, while the avena byzantina species accounts for most of the remaining production. The avena nuda species may gain importance in the future because of its hulless characteristics.
When mature, the oat plant is about 36 inches tall, and has several stalks per plant. The oat seeds are covered with a thick hull (except avena nuda, which is enclosed in a papery sheath). There are normally up to four seeds per sheath, and the seeds hang on very fine, wiry stems. There are many of the seed sheaths per head, and the entire grain head can be up to eight or ten inches long. Canadian and domestic oats are planted in April/May and harvested in August/September.