Conditions have been ideal for the rampant spread of 2 diseases over the past 3 to 4 weeks, warm days cool nights, very high humidity, little wind / air movement and heavy morning dew containing leaf exodus (Guttation) rich with nutrients create conditions perfect for disease infection and spread.
The degree of humidity and calm winds along with the length of time we have experienced these conditions is unusual for us, while we usually have a few days at a time, the past few weeks have consistently been very Humid with little to no wind, this has contributed to the unusual severity of the disease, namely Dollar Spot in the fairways.

Dollar Spot is so named because of the initial dollar size spot, symptoms start as, as these spots enlarge they can coalesce developing into much larger irregular shaped patches, this is what you are seeing in the fairways at the moment, they may look like large dry areas but these straw coloured patches are damage caused by the dollar spot disease.

Unfortunately a problem with blogger is preventing uploading of pictures but will once the problem is sorted.

Generally we experience 2 main periods for Dollar Spot disease, in Spring and Autumn when the conditions described above are at their peak, generally our policy is to prevent the disease becoming active in the Bent Grass Greens, limit damage to Tees, and ride the worst of it out in the Fairways. Plant Protectant use is only considered for greens, to a lesser extent tees and not for Fairways as our priority of sustainable management for our turf surfaces. As you will notice, even though conditions are as they are, the greens remain disease free, the tees have more than the greens but nowhere near as bad as the fairways, highlighting the priority of areas. We simply do not have the budget to consider large area protective applications.

We rely on cultural means for control in the fairways, in the most part this is effective in reducing the severity and frequency of any diseases we may experience, however when conditions are as they are at the moment, we are simply at the mercy of weather conditions, once these improve, the cultural practices we employ have a greater chance of working and gradually we overcome any symptoms of disease.
As I said we simply have to ride the worst of it out. 

One of the most effective tools at our disposal during these periods is the removal of dew early morning, which contributes to the disease severity, The front 9 can easily be removed with the auto retic however the back 9 can take up to 2 hours to finish due to the manual retic system, one reason why the back 9 fairways are  far more effected than the front and another less than obvious advantage to the auto retic.
Other cultural practices include the targeted use of nutrients and their application and in smaller areas such as tees, collecting leaf clippings to limit the spread of infected material.

Popular posts from this blog

Hydraulic Oil Leak

Saltene and Couch Grass

Course Notes January 2020