An Experiment in Ice Removal

Sorry for the length and delay of this post.  It has been a busy time at the golf course.  Yes, we do get busy in winter!  There are only three of us on staff through the winter and there is a lot to do.  While writing this I also discovered there is need for a few other blog posts relating to why we aerate late in the season, why ice build up on greens is worrisome, and what keeps the Turfcare Department busy in the winter.  But in order to shorten an already long blog post, I will try to get around to these topics in the New Year.

Ice formation on the surface of greens is never good and my collective experience with ice at Greywolf has not been positive.  As I reported previously, we have a thin layer of ice that has formed on our untarped greens (8 of our 19 greens).  The ice layer formed as the result of two rain events in late November and early December.  The ice varies between 3mm and 6mm in thickness.  Although not very thick, I believed ice covers most of the surfaces on our untarped greens.  I believed this because after each rain event we went out and dug snow pits on the greens in order to examine the turf.  We also pulled out a few turf samples to measure the thickness of the ice (See my last two posts).

On December 7^th we undertook an experiment to see if we could clear the ice from the surface of the 10^th green. The goal was to clear the ice and not cause any damage to the turf.  Another goal was to see if our sampling program was correct in predicting the amount of ice coverage on the untarped greens.    

Assistant Superintendent Colin Matheson starting snow removal

Snow Removal on 10

The advantage of experimenting on the 10^th green is that it is right next to the Turfcare Facility and clearing a path to the green was not difficult.  On December 6^th we cleared a path in preparation for snow removal on the green.  On the morning of December 7^th, Assistant Superintendent Colin Matheson and I began removing the snow from the green with walk behind snow blowers.  The snow depth averaged 13” and removal took approximately three hours.

Towing Aerator to 10 Green

We then moved our aerator onto the green.  This required us to tow the aerator with our tracked John Deere Gator.  We then took the aerator, which had talon or star tines installed on quad blocks (that is 60 solid aerations tines) and attempted to chip or fracture the ice off the green surface.  We experimented with different depths of aeration to try and find the optimal way to remove the ice.  We soon discovered that no matter what depth we set the aerator, we could not fully break through the ice.  To improve the chances of success we also tested several spots by running the aerator over them multiply times.  In some instances we ran the aerator over the same spot four times.  The following video shows some of the work and the results.

In terms of ice removal the experiment was not successful.  During aeration small chunks of turf were removed from the green.  After aerating some spots multiple times, we discovered that only 15 to 20% of the surface was exposed.   Also in the fifteen minutes the aerator was in operation over 10% of the aeration tines (7 of 60) had fallen out due to strain on the mounting system.  The aerator was tested to the limits of its design.  Because of our limited success in fracturing the ice, the amount of turf that was being removed and the strain on the aerator we stopped the experiment.

The results after three aeration passes -  Bottom of photo no aeration  - Top three passes

Our experiment proved two facts.  By removing the snow we proved our hypothesis about ice coverage from our sampling program was correct.  The green surface on the tenth green was 95% covered by a thin layer of ice.  We also discovered that we had caused more ice by walking on the greens in order to inspect them.  After the green was clear of snow we could see individual ice foot prints that were over an inch in thickness.   Even though we had waited for two to three days after the rain to collect and remove samples, I believe the snow we were walking on was still saturated with water and by compacting it we had caused thicker ice to form where we walked.

Another observation we made after clearing the ice was that the thin layer of ice strongly adhered to the surface of the green.  There are several reasons for this.  First, the green surfaces had aeration holes left over from late season aeration.  When the ice formed on the surface, the ice essentially installed “footings” or “pilings” into the aeration holes in the root-zone of the greens helping the ice to adhere to the surface.  Also as a sound agronomic practice, the greens had been allowed to grow out in preparation for winter.  The height of cut had continually been raised during September and October.  The longer leaf blades helped the ice bond to the surface of the greens (An analogy would be if you had to remove ice off of your head – it would be easier to remove it off a bald scalp rather than long hair?  Sorry to all the mullets out there).   The type of ice also influenced removal.  Although the ice we have is thin, it is clear and dense.

So what can be done to mitigate the damage at this time of year?  Not much.  I believe our best course of action is to remove the ice as early as we can in the spring.  We are a month and a half into a five and half month winter season.  There is the potential for more rain.  My hope lies in the fact that the ice is thin and there are about 10% of the leaf tips poking through the surface.  After speaking with Jim Ross at the PTRC we are hoping the ice fractures enough from natural causes and there is enough gas exchange along the surface of the exposed leaf tips to sustain the winter.  I am also hopeful these are our eight healthier greens and that they went into winter in a hardier state.    

The final conclusion from our experiment is that ice removal after the fact and in our climate is very difficult and risky.