In 2005, approximately 10,000 acres were planted in Sudan grass valued at $5.5 million.
In Yuma County, Sudan grass is grown for hay and for its seed.
Sudan grass is one of the highest yielding summer annual forage grown in Arizona.
Sudan grass is a warm season grass known for being drought resistant. It is more efficient in water absorption because it has twice as many roots as corn and has only half as much leaf area as corn for water evaporation.
Sudan grass can grow as tall as 9 feet.
Sudan grass yields slightly lower than corn when harvested for silage, but it has the advantage of being able to cut 2-3 times during the season and it can also be stored as compressed or uncompressed bales or cubes.
Sudan grass and other members of the sorghum family contain a glucoside that breaks down to release hydrocyanic acid also known as prussic acid. High prussic acid levels may be lethal to cattle as high blood levels of prussic acid interfere with respiration and cattle can soon die from respiratory paralysis. Prussic acid will breakdown in one to two weeks, so material made into hay or silage is safe to use.
Planting starts in late February and continues through July 1. The amount of early planting depends on weather conditions, other crops being grown, and market conditions.
The crop is irrigated three to four times before the first cutting. The crop is then irrigated twice between other cuttings.
Early Sudan is harvested 70 to 90 days after planting. Late planting Sudan is harvested fifty-five days after planting due to increased soil temperatures. Sudan is normally harvested three times between May and October. The majority is harvested in May, June, and July.
Once the Sudan is cut, it takes seven days to cure completely.
For a faster recovery following cutting 4-7 inches of stubble remains after harvesting.
The crop may also be harvested just once to get maximum volume in one cut system.
Sudan grass dries slower than alfalfa because the stems are thicker and contain more water.
Once Sudan grass begins to flower, the quality and feed value drops drastically.
As the crop matures, protein content drops rapidly, while fiber levels increase. This decreases the feed energy value and rumen digestibility.
Sudan grass can contain as much protein as mature alfalfa, but only if harvested at the vegetative stage and not the flowering.
Sudan grass is a tall, coarse annual (Sorghum Sudanese) of the family Gramineae (grass family), probably indigenous to Africa, it is one of the longest-cultivated plants of warm regions there and also in Asia – especially in India and China.
In the United States, sorghum is grown throughout the Great Plains area and in Arizona and California.
Source: Kurt Nolte is an agriculture agent and Yuma County Cooperative Extension director. He can be reached at firstname.lastname@example.org or 726-3904. For additional information please visit https://extension.arizona.edu/yuma.