The Project 2021 - Update #18

 

Bentgrass

Our renovated greens are being seeded with a 50/50 mix of two creeping bentgrass varieties that are intriguingly named 007 and 777.  Why bentgrass, how are they developed, and why these names?

Bentgrass is an ideal grass for greens if your local environment can support it.  It can withstand foot traffic even if closely mown (down to 1/10 of an inch). Bent, by nature, is a cool season grass which is why they have been uncommon in the South.  Granite Bay’s cool nighttime temperatures allow bentgrass, especially the newer varieties, to flourish.

007 and 777 are part of a new generation of “Super Bents” that are more disease and heat resistant than their predecessors.

#1 Green bentgrass seed germinating and visible 7 days after initial seeding. 12 to 14 days after seeding we will start to lightly roll and mow the new greens.

How New Varieties Are Developed

How bentgrass varieties are developed is fascinating.  If you guessed mad scientists in a lab, you’d be partially correct.  They were developed by scientists in an outside lab but they aren’t mad, they are patient.

New  varieties are grown from samples collected actual golf courses.  This has been going on at Rutgers University for over 70 years.  Some quotes from www.bentgrassdoctor.com (the website of Dr. R.H. Hurley, the world’s premier expert on bentgrass).

Over the past forty years turfgrass breeders at Rutgers have visited hundreds of old well established golf courses throughout the United States. During a site visit small patches of putting green turf are collected. The only plants identified for collecting are ones that appear to be attractive, fine textured, dense, upright growing and free of disease.

Some of the older putting greens observed are over eighty-five (85) years old, dating back to the 1920’s, and we feel that some plants collected have been growing and surviving, under the wear and tear, on actual greens, for generations.

The goal has always been to find the idealistic 'one in a million' rare bentgrass plant -- those unique plants that display improved qualities with special adaptive traits that have allowed these plants to survive on a golf green, under extensive foot traffic and low mowing, for many, many years.

These promising wild varieties of bentgrass are brought back to the laboratory (turf farm) and observed for a few years.  Perhaps only two-percent of the promising varieties will be kept for further study with up to 98 percent of the samples discarded. These two-percent are propagated, studied, and grown to produce breeder seed.  And yes, this takes time:

Having patience is most important, as it typically takes an investment in time of approximately 12 to 15 years to collect germplasm, evaluate, breed, and commercially release one new variety.

Every architect and golf course builder has their own style of seeding greens. Basically the process is add pre plant fertility to the newly shaped and compacted  sand mix surface, seed at the specified rate, and incorporate  the fertility and seed into top 1/8" of mix. Then you start to irrigate very lightly on the hour during the day to prevent the young seedlings from drying out.

Major Advantages

So now that you have 007 and 777 varieties, what are their major advantages over previous generations of bent?

·        Improved disease tolerance

·        Improved drought and heat tolerance (777 is being planted in Texas)

·        Denser growth that limits poa annua establishment

So, what about those unique names?

Dr. Hurley’s first improved creeping bentgrass variety was named L-93 after the year it was first commercialized in 1993. 

 For his next bentgrass variety, the experimental designation was DSB (Dollar Spot Resistant Bentgrass) and the year it was to be commercially released was 2007.  Following Hurley’s earlier precedence of naming a bentgrass variety by the year it was to be released, the commercial name for DSB bentgrass was identified as 007. 

 Now, with Hurley's latest creeping bentgrass the commercial name will be 777 after October 2017 when this new “super bent” variety will be commercially released for sale to golf courses.

 

 Thanks to Ed Reeder for researching and writing this update while I was in a irrigation ditch.