Trees and Disease

It was just a gorgeous morning today as we started our fall aeration on greens.  This picture is showing the sand application to #3 green.  Yes it's pretty dusty and that's because we're using dried sand.  Normally the sand has some moisture to it and it doesn't look this dusty. While I was standing on the green taking this picture I also took some pictures of the disease popping up on the back of #3 green.  Look here.

This disease is called Fusarium Patch and it is very common in the Pacific Northwest on Poa greens.  Here's another picture I took this morning of Fusarium Patch, but this was taken on the back of #4 green.  

You might be thinking these disease spots are really small and no big deal.  That's only true because we noticed this disease coming on early last week when the weather cooled down and so we immediately applied a plant protection product to stop the infection.  If we had not made that application, there would be significant turf loss in these areas.  So why do these areas have disease popping up and other areas do not?  That's pretty simple and I'm sure you can tell by looking at these pictures that these areas are surrounded by trees.  No, I'm not saying trees cause disease.  It's always disease pathogens that cause disease, but a plants natural defense mechanism cannot work well when the plant suffers from shade. Trees cause the shade which weakens the plant and then the plant becomes susceptible to disease.  In addition, trees restrict air flow and that makes the environment in these shady areas more conducive to disease.  So now you have grass plants weakened from shade living in an environment that has more disease pressure.  To make things worse, if you loose turf to disease in these areas, it takes forever for the turf to recover since the turf in these areas are weekend by the shade.  It's the perfect storm really.  Shade is an absolute killer on a golf course.  Selectively removing trees is the most logical solution since it will both improve the environment and improve the plants health. 

Right now there are 36 trees on the golf course that are marked with orange ribbon because they are scheduled to be removed this off-season per the Club's Tree Management Plan. Some of these trees are being removed because they compete for sunlight and are compromising the quality of the golf course.  Some of these trees are being removed because they are simply in the way of golf and so they also are compromising the quality of the golf course. If you would like more information on the reasons surrounding the removal of these trees, click HERE to download this years project summary.   By the way, disease incidence is only the tip of the iceberg when it comes to the true cost of trees.  For a realistic picture of what a tree really costs, this article is always a good read, click HERE.