2 – 4 – 6 – 8 We Don’t Need To Cultivate August 16, 2010 By Bob Vavrek

Excess organic matter can clog air-filled pore space and make the soil susceptible to black layer and regionalUpdateContent decline during prolonged periods of hot, wet weather.  A sound coring and topdressing program is a good insurance policy during stressful weather.

There are plenty of reasons why many putting greens across the region have had difficulty surviving the unusually hot, humid weather this summer.  Disease diagnostic labs have been working overtime to make sense out of sample after sample of dead or dying grass.  All the usual suspects, such as basal rot anthracnose, take-all, brown patch, summer patch and Pythium are making the rounds, as well as some new faces, such as bacterial wilt.  Then there’s just plain old cool season turf melting away due to warm season weather conditions, without even the slightest sign of disease activity. 

The 20 to 30 inches of rain falling on some courses since June 1 st has definitely fanned the flames of turf decline.  No doubt, either too much or too little water has caused considerable stress to playing surfaces, especially Poa annua greens that have few healthy regionalUpdateContents any deeper than a half inch by the middle of July.  Delay syringing by just an hour or two when Uncle Wilty makes an afternoon visit has often been the difference between live and dead turf the next day. 

It’s easy to blame the weather for bad greens this summer, but in my opinion, it was just a matter of time before significant summer losses of turf were going to occur at some courses.  These courses, for whatever reasons, have not made managing organic matter in the upper soil profile a priority.

Twenty years ago, it wasn’t hard to find a course that cored greens twice a year with 1/2-inch tines, and the same course often dumped a considerable amount of sand on the greens every three weeks. Sure, golfers would gripe, but the grass on greens had the benefit of growing in a medium that resembled the finest 80/20 mix money could buy. 

Fast forward to 2010, and organic matter management might mean coring with ¼-inch quad tines during late October, and two walk-behind spreader loads of sand per green each week.  Granted, this might work for that occasional course that applies very little nitrogen and has very little play.  However, for most courses with the “we don’t need to cultivate” attitude, the upper soil profile of the greens begins to resemble a peat bog within a few short years.

One can make a pretty good argument to not want to core and topdress the greens.   Declining golf revenues, golfer annoyance, cost/labor issues, etc., etc.  The darn thing is that organic matter doesn’t really care about the economy, guest play or your budget.  It just keeps on accumulating regardless. 

During a mild summer, excess organic matter accumulation in the upper regionalUpdateContent zone is not much cause for concern.  Maybe a soft, overly receptive surface or some pitted, skiddy ball marks; though you won’t find too many golfers complaining that the greens hold too well.

On the other hand, all that extra organic matter clogging up the greens is definitely something to worry about when constant rain and a transition-zone-type summer settles in to the upper Midwest (and elsewhere) for a couple of months.  Some blame diseases, but for many courses that neglected core cultivation and topdressing for the past several years…… it’s simply time to pay the piper.   

Source:  Bob Vavrek, or 262-797-8743