Orgro

Spring dead spot is the only true affliction to Bermuda grass. It is a fungus that attacks the roots, stolons, and rhizomes of the plant. The infection occurs in the fall and winter. The fungus does not directly kill the plant but weakens it enough to allow winter to cause sufficient injury that the plant dies. Damage is seen in the spring when healthy Bermuda grass starts to break dormancy and infected sites do not.  There are far more questions than answers in regards to control, severity, and practices for prevention of this disease.

Recently, the use of organic compost in the fall has shown positive results. Several courses in North Carolina have been using these materials for a couple of years and have seen improved control of spring dead spot. There is only trial evidence thus far, but it is a relatively inexpensive and easy program to start. So in order to try and alleviate the spring dead spot problem we have, this fall we are adding this compost material, called Orgro, into our preventative maintenance routine.

This past week you may have seen us out spreading the compost or seen it in the fairways. The material will help relieve soil compaction which is one of the key strategies in fighting spring dead spot. Like most turf grass fungi, the pathogen attacks weakened and stress plants first. Compacted soil does not drain well and therefore the Bermuda grass is saturated and can’t breathe. The plants in this situation are susceptible to infection with the spring dead spot fungus. Also, the compost works as a fertilizer. Soil microbes break down organic material in the soil which releases nutrients that are then available to the plant. Soil microbes are active when soil temperatures get warmer, as it does in the summer. So, this material will be present in the soil as temperatures climb next spring and into summer, thus releasing nutrients to the fairways just as they are breaking dormancy and need food the most.

To work around a busy fall golf schedule we are splitting the recommended rate of application in half and will be applying the material twice. Our hope is that putting less material out will allow the fairways to grow over the compost quickly so as to impact playability as little as possible. However, we will not spread the two applications too far apart. One application is being applied at the start of the month and the other will be right near the end of the month. The timing of the application is important too because if applied too early, the material will begin to break down now and the Bermuda grass will take up nutrients. This would cause the Bermuda to grow too much as it heads in to fall which does not allow it to prepare for winter dormancy. This is another stress on the plant that can open the door for spring dead spot infection. If applied too late, the compost will sit on top of fairways that are not growing and the material will take far too long to be integrated into the soil. This would greatly affect the playability of the fairways. Also, the material would then not be in the soil through the winter, providing what defense it can, when the spring dead spot fungus is infecting the Bermuda grass.

Although, there is no way of completely preventing spring dead spot, we hope that by adding this new wrinkle to our management practices, we can see an improvement in the control of the disease.

 

See you on the course!

Joe

jvillegas@bwrc.org