The Heat Goes On! August 19, 2010 By Darin S. Bevard

In parts of the region, the oppressive summer heat is still hanging on and continuing to take its toll on cool-season putting greens. Bermudagrass, however, forges ahead. In our travels, we continue to see damaged turfgrass from the hot summer. Daylight hours are getting shorter, which helps the turfgrass by reducing the number of hours the grass is under stress. It is time to implement programs to promote recovery, but be careful and be flexible.

Traditionally, many golf courses schedule aeration in mid-August, and normally this is just fine. However, after this year’s summer weather patterns, timing may need to be altered or the aeration process should become less abrasive to the grass.  If greens are healthy, aeration can proceed as scheduled.  Several golf courses have already aerated greens without problem.  The key is to limit aggressive dragging that could damage the weakened grass. 

If your greens are very weak or have significant damage, delay aeration until after Labor Day.  This timing may provide some conflict with the golf schedule, but extreme times call for extreme measures and compromise.  Aerated greens are no fun to play on, but they are far better than dead or damaged greens that may result from being too aggressive with aeration and topdressing when the grass is too weak to handle it.

Where significant turfgrass has been lost on greens, incorporate seed in the very near future (if not already).  Dimple seeding, Job Saver tines, and spiking are all options to incorporate seed.  Vertiseeding is also an option, but be careful, as vertiseeding can disrupt the integrity of the surface and further reduce playability, especially on thin and open turf.  If large areas of damaged grass are not present, use less disruptive seeding methods.

Spoon-feed fertilizer with liquid applications in the short term, and perhaps light applications of a high phosphorus starter fertilizer could be used to promote seedling development.  Apply extra fertilizer until all of the grass has recovered and no bare ground exists.

Closely monitor mowing strategies.  The temptation to limit mowing while the greens are recovering must be carefully balanced with the need to prevent scalping of rapidly growing grass.  During some recent visits, recovering greens have actually suffered from scalping because of infrequent mowing.  There must be a balance, but once the grass is growing aggressively, routine mowing promotes lateral growth and limits scalping potential.

Growth regulators are another subject.  Once the grass has recovered, resume growth regulator applications at light rates.  This helps manage excess growth/scalp damage, which could occur.

On another note, the third round of annual bluegrass weevil adults for the season have been on the move.  Monitor closely for adult weevils.  Contact insecticides provide good control of adults.  The goal is to kill the adults before they have an opportunity to lay eggs or possibly kill adults that may be on their way to overwintering.  Do not ignore these insects.  They have caused severe damage at several courses where their presence was overlooked.

Better weather patterns are emerging.  Shorter days and cooler temperatures are promoting more aggressive turfgrass growth.  Virtually every golf course that we have seen recently has had some amount of turf injury due to the hot summer. Recovery will require patience, seed, fertilizer, plugging and possibly even resodding the most damaged areas. While the grass may have declined suddenly, it will take some time for recovery to occur.  Be patient and give the staff time to complete the work needed to return the golf course to its usual level of conditioning.

The Mid-Atlantic Region agronomists are part of your agronomic support team.  If you have a question or concern, give us a call or send an e-mail.  Stan Zontek ( and Darin Bevard ( at 610/ 558-9066 or Keith Happ ( at 412/ 341-5922.