This report from Ross Kurcab, CSFM, was sent to us by AgPro Technologies, which hired him to evaluate its Turf Blend biological soil and plant stimulant product. Kurcab is president of Championship Sports Turf Systems, LLC, an independent turfgrass/sports field consultancy.

“I conducted a simple 8-week trial using bluegrass seeded into a typical sand-based (USGA) rootzone. I have also looked into the biological sciences behind the AgPro biostimulant products with the same qualifiers I have used for over 35 years evaluating products as a professional sports field manager, the same qualifiers I use now before I ever suggest product solutions to clients in my turfgrass/sports field consulting business.

This past summer, I conducted a simple experiment to evaluate AgPro’s Turf Blend product in a newly seeded Kentucky bluegrass in a typical USGA sand rootzone and into post install thick-cut Kentucky bluegrass sod. Seeding such a small and relatively slow-establishing grass like Kentucky bluegrass (Poa pratensis) into a relatively barren soil like a newly constructed rootzone typical on high-performance natural grass athletic fields is difficult, even under ideal conditions, from my experiences. Sodding mature Kentucky bluegrass onto the same sand rootzone mix in the outdoor conditions of chronic heat and drought stress brings challenges almost as difficult as seeding, in my experiences.”

AgPro Turf Blend Evaluation: Summer 2018

Hypothesis:

Newly seeded and sodded Kentucky bluegrass plots in USGA sand rootzones treated with AgPro Turf Blend will establish faster and better than plots without AgPro treatments.

Confirmed: Under the time and conditions of this experiment, visual evidence was found to support increased vigor and establishment in both seeded and sodded plots treated with AgPro Turf Blend and a simple fertilizer than the plots treated with fertilizer alone.

Seed:

Four plots were constructed in trays of 14×5 inches and 2 ½ inches deep. The plots were lined with a simple filter fabric to prevent sand from washing through drainage holes in bottom of the trays and sinking/eroding the plot. Clean, washed sand (USGA spec) was hand mixed with Canadian Sphagnum peat moss at 10% (by volume), as is commonly done in USGA sand rootzone constructions. Each plot was filled 2 inches deep with this rootzone mix and seeded with 1.0 grams of seed or the equivalent of 110 lbs/acre (about 2.5 lbs/1,000 sq. ft.) of a 5-way blend of Kentucky bluegrass (Poa Pratensis) varieties: SPF-30, Gaelic, Jumpstart, Shannon and Midnight in equal amounts. Seed for each plot was weighed on a digital scale and hand-sprinkled onto the 4 plots. Each plot was then topdressed with ¼ inch of same rootzone mix to “plant” the seed.

Sodded plots were grown outdoors in high heat, light and drought-stress conditions as well as high soil temperatures to best simulate real summer sodding conditions.

Sodded pots were irrigated to field capacity as needed to prevent severe drought, but waiting until there was visual signs of drought on the first pot before watering all 8 pots identically on each irrigation cycle. Sodded plots were mowed identically, as needed to prevent scalping to about 1-inch height of cut with hand scissors.

At construction, and on days 30 and 60 thereafter, all four seeded plots and all 8 sodded pots were treated with a simple Miracle-Gro all-purpose plant food. In a 25- ounce spray bottle, 3 small scoops of fertilizer were mixed into water. Treatments consisted of spraying 5 oz of this fertilizer solution onto each plot to ensure each received the same amount. In addition, two of the four seeded plots and 4 of the 8 sodded plots were treated on the same monthly schedule with AgPro Turf Blend biological supplement product. In a 25 oz. spray bottle, 3 oz. of AgPro Turf Blend was mixed in and sprayed on the same two seeded plots (Plots 2 and 3) and the same 4 sodded pots for each treatment.

All plots were watered as needed for germination and establishment, and to relieve drought stress identically each time irrigation was called for. Plots were maintained for 8 weeks and visually evaluated for health and vigor.

Results:

• Initial spray-bottle irrigation treatments tended to wash the small, newly planted seeds towards the edges of each box, where the majority of germination occurred. This did not affect the experiment.

• In the sodded pots outdoors, in a rock-garden micro-climate, Initial soil temps reached above 140 F on the first few days and so each of the 8 pots was wrapped in white tape to minimize solar heat buildup in the pots past lethal temperatures. Even with a white wrapping, soil temperatures regularly exceeded 90F on most days with soil temps cooling to around 60 F at night.

Under the time and conditions of this simple experiment, the two seeded plots and four sodded pots treated with AgPro Turf Blend and soluble fertilizer appeared to outperform the two plots treated with soluble fertilizer alone.

My professional opinion: Beyond the visual growth and development advantages I saw when seeding and sodding bluegrass into the sand rootzone, I like the simplicity, cost and ease of use of your product. I have had a saying I use in such evaluations. “Tell me what your product is, what’s in it and how/why it works.” You’d be surprised at how many products don’t make it past this initial filter of mine. I found that your printed material along with the label on my sample bottle to more than satisfy this standard. In summary, I found AgPro Turf Blend very easy and safe to use, very compatible to the fertilizers I mixed in with it and quite effective at growing and developing young bluegrass seedlings in a relatively barren sand rootzone as well as when sodding in summer heat; much better than in the plots using traditional (N-P-K) fertilizers alone. In managing any natural grass sports fields, or when advising field managers in my consulting work, I will absolutely recommend they try it for themselves and see the results that I have obviously seen.

SportsTurf