Graden Contour Sand Injection demonstration

On September 22 we did a demo of the Graden Contour Sand Injection verticutting machine on the upper portion of the putting green.  We had a lot of comments and questions about this area because of the unique white lines of sand that the CSI created in the putting surface and because many had never seen this process done before.  I wanted to wait a few weeks before doing this blogpost so we could see how it all turned out and how it recovered before making any conclusions on the process and its benefits, if any.

Here is a video of the Graden CSI in action.  From a superintendent standpoint I was very impressed with the amount of material the machine removed and how it completely filled the created groove with sand immediately behind the blades.  From a golfer standpoint, attested by some of our golfers who came over to watch the demo, I was impressed by how smooth and puttable the surface was directly following the application.  Because the grooves are completely, and immediately, filled with sand there is little to any detectable effect on ball roll.

The special auger of the machine which moves all the debris generated by the machine to the sides of the passes made for a very clean operation.  Using a backpack blower to move the material to the side would probably be helpful but all in all it is a very clean and easy process.

With the grooves filled with sand once you move the generated debris away you can easily see that the grooves are filled all the way to the top and thus you don't have any depressions or grooves that will affect ball roll and will help to shorten the recovery time and the amount of complaints we heard from golfers who putted across the demo area.

Our demo was done using 2 mm blades and we went to a depth of just over 3/4".  I did like how easy the depth was able to be changed and how the amount of sand placed into the grooves could be changed with just the turn of a lever.  With the ability to use 1mm, 2mm, or 3mm blades the machine gives many different cultural practice options to best fit the time of year, the amount of material one wishes to remove, and the amount of disruption to the surface needed or allowed.

The demo area that we used was about 1,100 sq ft and from this area we removed enough material to fill one of our Toro Workman MDEs one and a half times.  Considering that according to Graden literature we were affecting 15-20% of the putting surface, a yearly total value suggested by USGA, it was very impressive that we could remove that much material and not affect the putting surface anymore than we did.  We used the Graden Groundhog to remove the debris from the surface which was also very impressive but we will show that on a later post.

Here is the area on the putting green on the day of the demo, September 22.  It has been blown off and rolled.  Very puttable and the biggest thing that one could see was the stark white lines of the sand.  Picture at the top of this post is also from demo day.

This is a shot of the demo area on October 2. Just to make it clear, we did nothing special or extra to this area.  We did not place any additional fertilizer or water to the area to improve or facilitate recovery as we would during an aerification period.  I wanted to see under the "worst" of conditions how long would it take to recover and how would it look.

Here is the area on October 16 and it is virtually completely healed in.  The lines you see are completely covered with turfgrass and the extra oxygen, water, and nutrients being allowed to enter the root system are what is causing the darker green lines to be visible.

The demo of the Graden CSI machine was very impressive and the benefits of the machine are very evident.  Not only did we remove a lot of organic matter from the top of the putting surface but we were able to incorporate over 1,100 pounds of sand into this area.  I have noticed how much firmer this area is compared to the area just to the side which was not done.  I would like to thank Mike Crawford of Redexim Turf Products for setting up this demo.  Hope we will be able to purchase a few of these machines to help make the greens along the Tennessee Golf Trail even better.