Date of Award


Degree Type


Degree Name

Master of Science (MS)

Author's Department


First Advisor

Roger Darding


A field test was conducted to determine the most effective spring application timing and the most effective concentration for use of American Cyanamid's ACP1911 plant growth regulator. Three different concentrations of ACP 1911, also known as Event, were used for each of five different dates. The field test was conducted on rough turf at Coles County Airport, Illinois, in the spring and summer of 1987.

The dominant grasses in the test site were fescue (Festuca pratensis Huds.) and bluegrass (Poa pratensis L.).

Event was applied at concentrations of six, eight and ten ounces per acre on March 11, April 3, April 17, May 1 and May 16. Embark, a product of 3M Company, was applied for comparison on May 1.

Event was evaluated for the reduction in weight, from control, of material harvested from the test plots. Subjective tests on the height, injury, color, seedhead production, and weed control in the test plots were also conducted to support the weight studies. These common subjective tests are included for completeness.

It appeared that Event was most effective when applied at a concentration of ten ounces per acre regardless of application timing. Weight studies also indicate that, as time passes, later application dates become more effective than the previous dates: however, the overall percent reduction falls off. For the 5/14 sample date, the April 17 application date is most effective producing an 81% reduction from the control. For sample date 6/10, the May 1 application date is most effective producing a 78% reduction. Finally, the 7/10 sample date indicates application date 5/16 is most effective, producing only a 42% reduction. The subjective study on turf height supports the data from the weight studies. Later application dates also were more effective than previous dates, as time passed. Event, when used at the most effective concentration and applied at the most effective date, was superior to Embark at the reduction of turf growth.

Creative Commons License

Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.