It’s common for field experiments to last the duration of a growing season only to be repeated a second or third time in consecutive years. This can be annoying and confusing to the end users, the people who are awaiting the results of the project. So why is it that research projects are conducted across multiple years? Simply put, because of the environment.
Just think about the variation in the weather from last year to this year. Last year we experienced record low temperatures and moderate rainfall. This year we were treated to above average temperatures and record rainfalls. The difference in temperatures, coupled with the extremes in rainfall between the two growing seasons results in major inconsistencies in the growth and overall quality of our turfgrasses from year to year.
I’m seeing the influence of the environment in my interseeding study at Hyperion Field Club. The picture below shows two plots each receiving the same treatments or management strategy. The plot on the left is from 2009 and the plot on the right is from 2010. These particular plots each received 4 applications of Velocity herbicide on 14 day intervals at 2 oz/A starting the beginning of June and ending the middle of July. Each individual plot is split in half and received two different seeding strategies. The left side of each plot received multiple sowings of seed at 1.5 lbs/1000 ft2 every 14 days for a total of 13.5 lb/1000 ft2/year. The right side of each plot received two sowings of seed at the same rates for a total of 3 lb/1000 ft2/year.
|Research plots from Hyperion field club in 2009 (left) and 2010 (right). Each plot received 4 applications of Velocity. Why such a disparity in appearance? The environment.|
The plot from 2009 shows good color, no loss in turf density, and seedlings can be seen emerging on the left side of the plot. In contrast, the plot from 2010 appears slightly chlorotic and turf density has been severely compromised. Furthermore, germination of seedlings is scarce. Clearly, the weather was a huge factor in the response of these plots to the Velocity applications. To be fair, I do need to point out that the Velocity label warns of possible damage to creeping bentgrass under high heat stress during and directly following application which was experienced in 2010.
If you’ll remember from an earlier post, one of the surprises from this research was the high level of poa control we experienced from the Velocity applications. Based on the damage we saw from the summer applications during 2010 we have set up another trial to see if we can achieve good poa control with fall applications of Velocity. The idea is that applications during the fall will result in less damage to the creeping bentgrass. This trial has three treatments, 1) some plots will receive a September 1 application, 2) some plots will receive an October 1 application, and 3) some plots will receive an application on September 1 and October 1. All applications will be made at 2 oz/A.
We’ll be sure to let you know how it goes…next spring.
|Velocity research plot (left) and untreated plot (right) at Hyperion Field Club. The plots receiving Velocity had considerably less poa compared to untreated plots|
|Side project to determine if fall applications are effective at controlling poa.|
Graduate Research Assistant