Managing Excessive Organic Material in Greens

Over the past couple of months we have been working very hard to recover our greens from the nematode infestation that we experienced coming out of dormancy as detailed in a previous blogpost Greens Getting Better Everyday.  With all the extra fertility we have had to apply to the greens to help them recover we have generated a lot more organic matter in the greens this year than usual causing them to be puffy, or have a "spongy" feeling, which reduces the firm, fast feel of the greens and allowing our greensmowers to start scalping and gouging areas in the greens.

We have worked too hard in getting the greens back to lay off of them now so that is why we got aggressive with our verticutting process this past week.  The whole idea of getting aggressive is to remove the stolons or top growth on the greens.  It looks very intense but is actually one of the best things we can do for our greens as it removes the excess growth in the greens, allows for more sand topdressing to be incorporated into the greens, creates a firmer faster surface, and reduces the potential scalping issues that we have been facing.

The greens were verticut in two directions at a depth of 0.125" below the surface using a backtrack mowing pattern meaning we verticut directly back up the pass we just did.  This is done to make sure all the green is consistently affected in the same way.

Verticutting or vertical mowing is accomplished by using blades which are set in a vertical position, thus the name, and designed to penetrate the surface of the greens to remove stolons and excess growth on greens.  The depth at which the blades are set determine the amount of material removed and the disruption to the putting surface.

So why do we spend the extra time and energy to backtrack mow?  The set up of the verticutting units and the growth habit of the greens to grow downhill and toward the sun requires this to insure a consistent affect to the entire surface.  The top picture shows the units going up hill or "into the grain" so the blades are actually not affecting much turf.  The bottom picture shows the blades going downhill so that the teeth shown above are actually reaching under the green surface and pulling the turf upwards.  If the greens were only verticut in one direction then every other pass would be affected more than the other and that would result in stripes across the green which would affect play and appearance for a very long time.  And no one wants that.

After the greens were verticut we used a tow behind turbine blower to remove any excess organic material from the greens surface before it was double cut with our sand reel mowers set at 0.130 and then single cut with our regular cutting units set at 0.120.  The amount of material removed from the greens is unbelievable and I wish there was a way to collect it all and pile it up so everyone could get a grasp of what is going on under that putting green surface and why these processes are necessary.

After the greens were double cut and then single cut they were moderately topdressed and drug in and then watered.  We really opened up the canopy of the greens with this process and the sand worked right into the voids we had created, so much so that we were able to come back on Wednesday morning and apply another dressing with sand to finish the process off and smooth the greens up so much more.

So on Wednesday some of the greens looked like this which did give credence to some of the comments we heard like "What have they done to the greens now?" or "They just got them back and now they have torn them up again".  But the greens putted very well considering their appearance just proving you should not judge a book by its cover.

So by Friday the greens were healed in from the verticutting process and better than they have been all year.  It takes some work to get and keep greens in the condition that golfers demand and as we are not closed one day a week for maintenance we have to perform these tasks when we can.  Normally we would not have been this aggressive during the playing season, and would have waited for our summer aerification closure, but this needed to be done and if I could I would do it again next week.  Don't worry I'm not.  Thanks for your patience and I hope you agree with me that the final result was worth the couple of days of pain.