Turf Magazine - October, 2013

FEATURES

Azospirillum, Bacteria that Improve Turf Health

By Doug Kremer


Grant Trenbeath, head groundskeeper at Chase Field, Phoenix, seeks every advantage in growing grass at his indoor facility with its retractable roof.
Photo courtesy TerraMax, Inc.

Professional turf managers spend significant amounts of time growing and maintaining healthy turf. Grounds crew managers and sod producers are all after the healthy, smooth turf their customers require - and wear and tear on these surfaces can be extreme.

Chemical inputs have long been the industry standard for maintaining the vitality of the turf. However, concerns about the environmental and financial impact of these products has led turf managers and sod producers in a new direction - microbial inputs.

Inputs containing microorganisms can promote turf growth while minimizing the usage of fertilizers and pesticides. There can be as many as 10,000 different microbial species existing in a gram of soil, and there are bacteria that can help protect and nourish plants if present in large enough numbers. Microbial inputs can help increase the population of helpful microorganisms in the living soil.

For more than 10 years, TerraMax, Inc., Bloomington, Minn., has producing products that rely on the bacteria Azospirillum. Acting as a nitrogen "fixer," Azospirillum harvests nitrogen from the air and soil and delivers it to the plant. The bacterium is proven to improve root structure year over year and impact plant growth. By absorbing and anchoring into the plant's root hairs, Azospirillum can help plants naturally absorb more nitrogen, making plants less dependent on manufactured nitrogen fertilizers.

Chase Field, Phoenix, Ariz.

Home to MLB's Arizona Diamondbacks, Chase Field sees plenty of activity throughout the season. In addition, the field hosts a variety of other entertainment events, such as motocross races and monster trucks.

In his 16th year as head groundskeeper, Grant Trenbeath tends to the site's natural grass, which is grown in a retractable-roof environment. Sunlight and the ability to grow natural grass in an indoor setting that sees high-end, high activity are paramount concerns for Trenbeath.

Without the durability like outdoor stadiums and the inability to re-cooperate as fast, Trenbeath was looking for a product that would increase root mass and density and sustain high wear and tear. Trenbeath began using TAZO-B, an Azospirillum bacteria product, last season and saw immediate success. He is now in his second season using the product, applying it to the field once a month.

Not familiar with Azospirillum-based products, Trenbeath's interest was piqued by the product's potential to increase root mass.

"Within the first year, there was a noticeable difference. The increase in root mass and density is night and day compared to what we had before," says Trenbeath. He adds, "I became a believer early on and it is now a part of my regular maintenance applications."

Uhl Turf Nursery, Memphis, Ind.

The drought of 2012 hit hard for Uhl Turf Nursery, Inc. in Memphis, Ind. Operator Jeff Uhl produces 110 acres of turf annually and turned to Azospirillum as a way to recover turf affected by the dry conditions. While all of his turf fields struggled under severe drought conditions, Uhl was shocked to see how much better the fields treated with Azospirillum held up.

Uhl doesn't irrigate his turf and he found that after only two spray treatments of the specially formulated bacteria, the root development had noticeably increased.

He said he had fields that were fried, but once they got a little bit of moisture, the fields treated with Azospirillum greened right up.

"The results were remarkable. I am very optimistic about using it in years to come to protect against the effects of droughts and to increase root growth," Uhl added.

Industrial Parkway Services, Marysville, Ohio

Mark Vollrath of Industrial Parkway Services in Marysville, Ohio, grows 30 acres of sod annually. Vollrath needed to achieve quicker and more uniform germination and he wanted to be able to harvest sooner. To address these needs, Vollrath used Azospirillum as a powdered seed treatment (TAZO-ST) to treat new seeds. The bacteria adhere to the seed coat and is available and viable at the time of planting. The bacteria exude compounds that stimulate root growth and create even more attachment sites for the bacteria.

Vollrath said, "I was able to harvest my sod (Kentucky bluegrass and fescue) months earlier and the sod has thicker roots and was more solid." He added that the bacteria-treated seed led to faster germination and provided increased stress tolerance.

Healthy turf begins at the root. While parent material, climate, topography and vegetation contribute to the function and performance of the plant, "fixing" roots with nitrogen, as Azospirillum does, greatly increases root structure; a key factor in better resisting changing climate conditions and daily wear and tear experienced by turf surfaces. Those caring for turf now have a more consistent and natural solution for treating their grounds or sod with Azospirillum.

Doug Kremer is CEO of TerraMax, Inc., Bloomington, Minn., produces microbial technologies for agriculture, horticulture and other applications. Visit http://www.terramaxag.com.