Agronomy And The Principle Of Calculated Risk April 13, 2011 By Adam Moeller

Core aeration is a highly beneficial management practice to produce firm, smooth, resilient putting greens.  If performed too early, when the turf is not actively growing, recovery is likely to be slow. 

Spring core aeration on putting greens is an extremely beneficial management practice that is being performed currently throughout the region.  Although each year it seems like core aeration is undertaken earlier in the spring in an attempt to reduce golfer displeasure.  Course decision makers and the superintendent often adopt the principle of calculated risk philosophy when determining core aeration dates.  This principle is very straightforward.  There are risks involved with an action, in this case early spring core aeration, but there also are possible benefits of this risk. 

Early spring core aeration and cold weather lead to a long recovery time while warm spring weather leads to a normal recovery time and greens free from disruption for most of the spring.  Every golf course is different, but, for many, a long recovery from early spring core aeration annoys golfers much more than a quick recovery from core aeration performed in mid-spring.  At golf facilities that want the shortest core aeration recovery time each year the solution is easy; core aerate in mid-spring once the turf is actively growing.  For areas in the southern tier of the region, this could be mid April while for golf courses farther north, this could mean early May.  Bottom line, early spring core aeration performed when the turf is not actively growing is going to lead to a long recovery time.  Some years early spring core aeration may work well, but, in most years, it will cause longer recovery.  For more detailed information, read: Core Cultivation: Timing is Everything 

Many golf course superintendents are preparing plant protectant applications targeting annual bluegrass weevil (ABW) adults, an extremely devastating insect in the region.  Traditional timing for the adult ABW coincides with the half green-half gold stage of forsythia shrubs.  Using forsythias as an indicator should not be the sole factor in determining application timing though.  Frequent monitoring with linear pitfall traps and/or lemon scented soap flushes is important for accurately timing these applications.  Adult ABW have been found at many facilities in NJ, CT, NY, and portions of MA, but peak activity can be difficult to predict without frequent and diligent scouting.

Poa annua (annual bluegrass) seedhead suppression applications also are being performed.  Plant growth regulators can be used with good success, often 50-75 % seedhead control, but accurate timing is the biggest challenge, similar to ABW control.  Growing degree day models and frequent scouting are the best means for determining application timing.  These models, in addition to personal observations, suggest that Poa annua seedheads are about to form on putting greens in the southern half of the region so these applications need to applied immediately if they haven’t been made yet.

As a reminder, there is no fee increase for 2011 Turf Advisory Service (TAS) visits if payment is made before May 15, 2011.  Take advantage of this year’s $600 prepayment discount.  Keep in mind, our fees include all travel expenses.  GCSAA Education Points are now available for Turf Advisory Service visits.  

USGA agronomists can provide insightful and invaluable information involving all areas of golf course maintenance, which will help maximize turf health, playability, and efficiency.  Contact Dave Oatis, Director; Adam Moeller, Agronomist; or Jim Skorulski, Senior Agronomist for a Turf Advisory Service visit this season.