Annual Ryegrass - VNS

Annual ryegrass, also known as Italian ryegrass, is an introduced, native to the Mediterranean region, short lived cool season annual . It germinates and establishes quickly and is used in both the northern and southern regions of the United States for erosion control, temporary turf, as a cover crop, and as a pasture grass. When compared to perennial ryegrass annual ryegrass is generally lighter in color and has a less uniform growth pattern. Annual ryegrass can be kept at heights of 2" to 3" for turf applications and can grow up to 24" to 36" if left alone. Annual ryegrass adapts to a wide variety of soils and prefers full sun. As a cool season, annual ryegrass germinates best when soil temperatures are approximately 50°F - 65°F. 

Annual ryegrass is often sold in two different flavors. Diploid and Tetraploid.

Diploid annual ryegrass has two sets of chromosomes. It is densely tillered, reliable, and does well in plantings that are less than desirable such as areas with low fertility or limited moisture. Gulf annual ryegrass is an example of a diploid annual ryegrass.

Tetraploid ryegrasses have four sets of chromosomes and have a higher cell to cell wall ratio. Because of this tetraploid varieties are larger leafed, are higher in soluble carbohydrates, are more easily digested, and are more preferred by livestock. Tetraploid ryegrasses have a more open growth habit. This can be utilized for planting with other species such as clovers. However, this characteristic can also allow for more weed pressure. Beef builder annual ryegrass is an example of a tetraploid annual ryegrass.