COURSE CARE
Layer Up for Extra Warmth - Pine Straw Layer Adds Protection for Winter Injury Prevention January 17, 2011 By Patrick O’Brien and Chris Hartwiger

A two to four inch layer of pine straw applied to an ultradwarf bermudagrass putting green before pulling on a light weight cover offers an additional level of winter injury protection. 

Ice and snow accumulation, followed by a bitter wind and Arctic cold air, blasted golf courses in the Southeast during the week of January 8 – 14, 2011, and the forecast this week has called for lows in the single digits in several southern cities.  Several superintendents with ultradwarf putting greens have taken extra precautions in addition to covers to reduce the risk of winter injury.   

At the Atlanta Athletic Club, home of the 2011 PGA Championship, Kasey Kauf and the maintenance staff on the Highlands Course added a two-inch layer of pine straw directly on top of the putting greens before putting on the lightweight covers.  The pine straw and cover will retain warmer soil temperatures during these extended cold times, according to Dr. Mike Goatley at Virginia Tech.   The effectiveness of this strategy has been observed for years in the region and affirmed in university-based research.  Refer to this link in the Green Section Record archives to see how well straw plus a cover performed under much harsher Canadian winter conditions (/content/dam/usga/pdf/imported/course-care/000911.pdf).     

This same technique of straw plus a cover was implemented by Anniston Country Club Superintendent Russell Nichols on several of his shaded or north-facing putting greens.  Russell was interested to see how effective this technique was.  On January 8, 2011, soil temperature measurements were taken in the top two inches on the #2 green prior to adding pine straw and the cover.  The air temperature was 40 degrees and the soil temperature was 38.  Approximately twenty-four hours later, the air temperature was 28 degrees and the soil temperature under the pine straw plus cover increased to 42.  Russell then checked the eighth green, and the soil temperature was 35.  Overall, Russell and the staff were pleased with the results and felt reassured that using pine straw plus a cover offered extra protection.    This information is summarized in the table below. 

Table 1:  Anniston Country Club Winter Cover Observations

 

Green Location and Description 

Date and Time 

Air Temperature 

Soil Temperature 

#2 Green Before Straw + Covering

1/8/11, 8:30 AM

40 degrees

38 degrees

#2 Green, Pine Straw and Cover

1/12/11, AM

28

42

# 8 Green, Cover Only

1/12/11, AM

29

35

 

When temperatures moderate again, the covers will be pulled off and the pine straw will be removed from the putting green surface.  Back-pack blowers will be used to remove remaining debris, and the putting green will be ready for play.  One of the benefits of using pine straw is that a good supply generally is available on a southern course.  It can be raked up, used for winter protection, and then reused elsewhere on the course afterward.  

It has been our experience that adding pine straw as an extra layer of protection should be used when temperatures start to get down into the mid to low teens or below.   At these temperatures, consider covering greens only that have significant winter shade or northern exposures.  If temperatures start to fall into the mid-single digits, or into negative territory, it would be a good idea to blanket them all with pine straw and covers.  Remember to keep a soil thermometer on hand to take readings at your course.  This will help fine tune what needs to be done.  

We thank Kasey Kauf and Russell Nichols for their assistance in this update.  We hope that these winter management tips will be of use to you.  Please do not hesitate to contact either of us with questions or comments. 

 

Source: Patrick O'Brien 770-229-8125 or patobrien@usga.org  and Chris Hartwiger 205-444-5079 or chartwiger@usga.org 

 

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