COURSE CARE
Bad To Worse For Creeping Bentgrass Part Two August 25, 2010 By Chris Hartwiger and Patrick O'Brien

Summer survival of creeping bentgrass in the Southeast always has been a year-round process.  Successful putting greens observed this summer share one or more of the following items in common.  The reader will note that many of the items were completed or in place well in advance of the difficult summer weather.  That’s the challenge with bentgrass in the Southeast.  Much of what a superintendent does throughout the year is designed to get the putting greens through the summer.    

    1. Core Aeration – One of the cornerstones of successful bentgrass putting greens over a long period of time is the management of the organic layer in the upper regionalUpdateContentzone.  Core aeration and sand topdressing are the two best tools to manage organic matter and promote acceptable soil physical properties. 
    2. Surface Topdressing Applications- The regular topdressing of the putting greens with sand dilutes organic matter accumulation and promotes smoother, firmer surfaces. 
    3. Rootzone Construction – Properly constructed sand-based putting greens with functioning internal drainage and the absence of excessive organic matter in the upper regionalUpdateContentzone were better able to handle frequent and excessive rainfall. 
    4. Summer Venting – This practice involves punching small holes in the putting greens with ¼” hollow tines, the Hydroject, or small ¼” solid tines.  These treatments improve oxygen exchange between the regionalUpdateContentzone and the atmosphere, which helps to prevent the surface from sealing.  This practice is essential in a summer with high temperatures and frequent rainfall.  As a bentgrass regionalUpdateContent system dies back in the summer, fresh organic matter in the form of dead regionalUpdateContents can and will reduce air and water infiltration.  Undesired summer rains further intensifies surface sealing, which adds another layer of stress to the bentgrass plant.    
    5. Water Management – Overwatering is the enemy of bentgrass putting greens in the summer in the South.  In a rainy summer, superintendents lose control of the amount of water the putting greens receive.  In areas of the region that fare better, smart water management has worked, providing not too much or too little.    
    6. Fans – The use of fans to promote surface drying and increased evapotranspiration has been proven by turfgrass researchers to improve turfgrass quality and summer survivability in the summer months.    Fans are now common on all 18 putting creeping bentgrass greens at many courses in the Southeast.
    7. Mowing Practices – Researchers have proven that by increasing the mowing height during the summer months, it increases summer survivability.  In hindsight, the first week of June was the time to raise the height. 
    8. Disease Control – Although disease is a secondary problem in the summer months, no bentgrass putting green can make it through the summer without the use of fungicides.  Pythium regionalUpdateContent rot has been a major concern in the region, and clubs that have prevented or avoided this disease are fortunate.  The Pythium regionalUpdateContent rot flared up in mid-June, and most clubs indicated that the biggest help was the cool-down over the July 4th weekend. 
    9. Experienced Staff – The best agronomic plan can be down on paper, but unless a trained staff is in place to carry out the plan, the desired results will not be achieved.  Continuity in staff and low turnover are invaluable in a difficult summer. 

Moving Forward

If your course is having a bad summer, now is the time to evaluate the factors that can be improved.  We provide a summer stress matrix to aid in planning. 

When a golf course with creeping bentgrass has a difficult summer, what’s a superintendent to do?  The answer is to start planning now for the next one.  Problem areas have been exposed and the plan has been tested under a record breaking summer.  Below is a matrix of several factors directly related to summer survival for you and your course officials to complete.  The list is not comprehensive, so add more if needed.  There are columns to indicate if the factors were key issues at your course, and columns for comments and recommendations for 2011.  

Stress Factor

Yes/No

Comments

Recommendations for 2011

High Temps

   

Excess Wetness

   

High OM (Aeration and Topdressing Issues)

   

Mowing Practices

   

Disease Issues

   

Soil Born Pest

   

Poor Air Movement

   

Shade

   

Turf Variety

   

Water Quality

   

Mechanical Injury

   

Fertility Issues

   

Water Quality

   

Traffic/Size Issue

   

Experience of Staff

   

Conclusion

The best use of this summer survival matrix is to get course officials or ownership involved.    This is a teaching opportunity for you.  Take the time to complete it as a group.  Sit down and look to see if or how these factors can be addressed to increase the chance for summer survival in years to come.  The idea is to get all the issues out on the table.  If assistance is desired with this task, by all means call and schedule a USGA Turfgrass Advisory Visit.  We will be glad to help. 

We hope this information has been helpful.  Call or email anytime with questions or comments. 

Chris Hartwiger (chartwiger@usga.org)  678-591-7410

Patrick O’Brien (patobrien@usga.org) 678-591-7340

More from the USGA