Greens Discoloration...What Is It?

With the wild swings in temperatures this spring, there have been a lot of unusual looking patches on the greens. primarily on the newer greens on Newport.  This spring, we have begun phase 2 of our poa control program on Newport.  You remember it began last fall and winter with eliminating it from the fairways.  Greens are trickier and cannot be 100% poa free, considering they are 14 years old.  This spring, we applied a seedhead control Embark, very early, because it was so warm.  Then, we had to move up our crabgrass preemergent to late March.  Combine this with extreme drought and introducing the regulator Trimmit, you have a perfect storm.  This is not damage or permanent.  My choices were do nothing and have seedheads and crabgrass.  The upper photo shows the poa stunted by all of the applications.  An unintended side effect of growth regulators is if we receive a frost, the creeping bentgrass can turn all different colors of yellows, purples and reds. 

The lower photo shows two distinct types of poa annua.  The pen is pointing to a patch of PERENNIAL poa annua.  This is generally fine bladed and does not produce a lot of seedheads.  This type is being University propagated for reproduction.  Some of the finest greens in the world are perennial poa, like Oakmont. The annual types are more bunchy and seedy, like the area by the chapstick.  This type is what I am trying to stun with the Trimmit.  Annual types are among the first to die from heat stress.  The perennial types are still disease susceptible, but are more manageable. We are using (picture this in your mind) a rate of 4-6 ounces of product per acre.  That is how precise these products are.  The early regulation helped smooth the greens when the poa was growing faster than the bentgrass.  To the right of the pen, you can see some of the red bentgrass.

So there is your explaination.  There is nothing wrong or unhealthy.  It is all part of a plan to produce better putting surfaces.  Why not do this on Seaside?  Those greens are much older and constructed differently.  The poa populations on Seaside are over 60%.  Newport still seems to be under 45%.  IF I tried to eliminate it all together, the bare spots would be much less attractive than what we have now.