Thursday, July 26, 2012

Bentgrass vs. Poa Revisited

Earlier in the year, I talked about the benefits of promoting hearty grasses like bentgrass over weaker grasses like Poa.  Right now, we sit in the middle of the golf season and I thought it would be a good time to update our progress. 

When I came to Ridgeway in 2010, our putting surfaces were 70%-100% Poa.  As we look at our putting surfaces today, almost all the greens with the exception of maybe 2,4, and the putting green have over 50% bentgrass.  Some greens like 1, 3, 7, 12, 14, 16, 17, and 18 have over 70% bentgrass populations. With greens like 1 and 12 having 90+% Poa just a couple of years ago, this is a remarkable turnaround.   

The results are staggering to say the least, and many of you have made positive comments on the progress. It just goes to show how making and following through with a plan to improve the long-term health of the greens at Ridgeway can be achieved with just a few key decisions.    

There are many factors that have benefited this proliferation of bentgrass; a few are: i.) improving sunlight around greens by selective tree removal, thus improving carbohydrate reserves, ii.) keeping the plant drier with more conservative watering practices, iii.)  changing  the fertility rates, type and timing, iv.) increased use of greens rollers and reduced mowing, v.) frequent deep-tine aeration, and vi.) XGD drainage.  Other factors like the weather have actually helped our cause this year.  Hot, dry weather has helped promote our bentgrass populations in harmony with our long-range, nutritional, and cultural practices.  

We will continue to promote bentgrass and hopefully will continue to see results, but there are a few long-range items that must not be overlooked.  Ridgeway has been dry all season, but once heavy rains come again like in 2010-11, bentgrass and Poa will be unhealthy.  The cure is simply identifying which greens are good candidates for either internal (XGD) or surface drainage.  Long-term drainage solutions in conjunction with our ongoing cultural and nutritional practices will go a long way in continuing the trend of making Ridgeway's greens healthy, consistent and playable.

Below are some pictures taken from earlier this year and some pictures showing the contrast between Poa and bentgrass roots.  It is astonishing to see the difference in root depth between the two grasses but it is also great to see such good roots after one of the hottest summers on record.

Picture of Poa roots 2-3" down
Taken July 2012

Bentgrass roots growing 9-10+" down.
Taken July 2012

#1 green taken April 2012
Notice how dense the lime green
Poa is on the left of the picture.

#1 green in the same as the picture
left in July 2012 almost
 100% bentgrass.