Tuesday, June 11, 2013

Yellow Spots on Collars???

By now most of you have probably seen the yellow "patches" in the collars around our putting greens.  Many of you may think this is a disease or unintended.  In fact, nothing could be further from the truth. 

Pictured above is the Putting Green collar illustrating the "yellow patches".  Poa annua has been injured but the surrounding bentgrass remains unaffected.  Why so?

The yellowing turf is the result of a very effective application of a selective herbicide known commercially as Velocity.  Velocity is a very good at injuring and/or killing Poa annua turfgrass.  The yellow spots are the result of a spot spray using a standard 2 gallon pump up sprayer available at any local hardware store.  This application method allowed us to deliver an aggressive rate of product specifically to the Poa annua without any risk of injuring the surrounding bentgrass.  The results of the application have been impressive to say the least.  While visually the turf has been compromised, the playability thus far has not.

The timing of this application was intentional.  As we head into the warmer portions of spring and summer, the bentgrass plants will thrive in the summer heat and humidity while the Poa annua will struggle.  The goal of this application was to cripple the Poa annua now and allow for the bentgrass to aggressively fill in these areas as the Poa dies back.  In the event, the damage becomes too severe, we are already prepared with over 2000sqft of sod to plug and or replace any area that becomes a nuisance. 

#9 collar:  The bent is thriving and the Poa annua...Not so much!!!
This and further applications will go a long way in preventing the encroachment of Poa annua into our wonderful new greens!!!