COURSE CARE
The Bench Versus The Actual February 2, 2011 By R.A. (Bob) Brame

The bench is important to a team, but it’s the players on the floor that are in control at any given moment during a game.  In a like manner, the mowing height bench setting on a mower is important, but it’s the actual cut that directly impacts turf health, dependability and playability.  Since mowing is a building-block component of golf turf maintenance, it is a common topic in turfgrass maintenance and during on-site Turf Advisory Service visits.  Often, the focus is on the bench setting, as opposed to the more important actual cut.  Isn’t that a bit like relying on the benched players to score points rather than those on the floor? 

Acknowledging the bench setting on putting-surface mowers seldom yields the same actual cut, it is important to consider this aspect of the maintenance operation.  The weight of the mowing units, the number of mowing units (i.e. a single-unit walk-behind mower versus a three-unit triplex mower), and the type of front rollers all directly affect any difference between the bench setting and the actual cutting height.  Turf density and soil moisture also can add to the variations between the bench and actual.  A prism gauge is the only real tool for determining and monitoring the actual cut.  This means every maintenance operation should have and use a prism gauge to cross compare the actual cut with the bench setting. 

This discussion must be carried one step further.  As the cutting height is reduced, there will come a point where eyesight limitations make it impossible to accurately determine the actual cut.  The quality of cut can be reviewed at any height, but ultra-low mowing blocks actual cut measurements with a prism gauge.  Commonly, this is somewhere around 0.120".  In other words, at or around 0.120", it becomes very difficult, if not impossible, to measure the actual cut.  The efficiency, flexibility and benefits of topdressing, growth regulation, fungicide applications, water management and lightweight rolling (overall turf dependability/playability) during harsh weather are compromised as the actual cut is reduced below what can be monitored with a prism gauge.  This would suggest staying at an actual cut that can, in fact, be determined and monitored with a prism gauge. 

The very difficult 2010 season served to reemphasize the importance of guarding or balancing agronomic building blocks (1.fertilization, 2. growing environment – sunlight and air movement, 3.water management= drainage/aeration + irrigation and 4. mowing – type of mower, sharpness and height of cut) with playability.  Now is a great time to comprehensively review the agronomic foundation in your maintenance program, and this means carefully considering, and later checking in the field, any difference between the bench and the actual cutting height – having the right players in the game will directly influence the outcome.

Your Green Section agronomist can aid in reviewing your maintenance operation to maximize the product presented in 2011.  In fact, we are actively scheduling visits for the coming season.  The price is the same as last year (half day - $1,800 and full day - $2,600) if visits are committed to and paid for prior to May 15th.  Beyond the early season cutoff, prices will increase by $600.  So now is a good time, don’t wait – call or email to schedule visits for your course.  In addition to on-site visits, we stand ready to assist in any way possible.

             

Source:  Bob Brame, bobbrame@usga.org or 859.356.3272

 

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