The Texas Agricultural Experiment Station has released a new turf grass for winter lawns that promises to be "dwarfier" and with a darker green color than previous releases.

The new turf grass is an annual ryegrass, Axcella 2, and is an "upgrade" from the original Axcella released in 2001, said Dr. Lloyd Nelson, small-grains breeder with the Experiment Station and developer of both grasses.
"Axcella was the first-ever annual ryegrass developed for over-seeding sports fields and home lawns in the southern U.S. during the cool season,"

Nelson said. "Axcella was selected to be a dwarf, but highly vigorous, grass that would maintain a green turf even at temperatures below freezing."

As a dwarf variety, Axcella forms a "thick, dense sod" but doesn't grow tall quickly and doesn't need to be mowed as often, he said.

The earlier release of Axcella had similar growing characteristics, but was a lighter green. The newer version comes closer in color to that of traditional warm-season grasses such as St. Augustine, and has a finer texture than previous releases.

Using a winter over-seeding means a homeowner or sports field manager can maintain a green and natural lawn or field throughout the winter, Nelson said.

Other ryegrasses are available for over-seeding, such as perennial varieties. But without proper management, perennials can persist well into the summer growing season, choking out warm-season varieties that come out of dormancy in the spring, such as Bermuda grass.

Like its predecessor, Axcella 2 dies out at the same time Bermuda grass is starting to green up, allowing it to produce a healthy summer lawn, Nelson said.

Three years ago, another ryegrass variety, Panterra, was released from Nelson's breeding program.

"Axcella 2 is improved compared to Panterra in that it is more uniform and has a finer texture than does Panterra," Nelson said. "However, both varieties are very good. Axcella 2 may live about one week longer than Panterra in the spring."

Nelson said Axcella 2 must be seeded around Oct. 15 when the soil temperature has cooled and rainfall is expected. The seed should be uniformly spread at from 10 to 15 pounds per 1,000 square feet.

The seeded turf should be watered by sprinkler irrigation for at least 30 minutes per day for five days, he said.

The five-day watering plan is needed for the seed to germinate and establish itself in warm-season sod.

"Planting prior to a rain event or a cool front should improve chances of obtaining a good stand of the new turf," Nelson said. "The warm- season sod needs to be mowed close, or at about 1 inch or less, but does not need to tilled up before over-seeding."

The use of over-seeded ryegrass not only gives a beautiful winter turf, it also strengthens sod during the winter and summer. Strengthening the sod is particularly important for soccer and football fields, Nelson said.

"Winter sports such as soccer and spring football can damage a dormant sod, but the active growing ryegrass will continue to grow and protect the dormant sod," Nelson said. "If a good stand has been established, the grass will also crowd out many winter and early season weeds. If wear spots occur during the winter, more Axcella 2 seed can be spot-seeded in the wear areas, and if watered they should fill in those areas."

In Texas, Axcella 2 seed will be sold through Estes Inc. and through numerous local seed companies or feed stores.

Seed supplies will be limited this year, but should be plentiful in 2007, he said.