Because of the nice dry climate we have in Southern Idaho we do not have as many issues with turf diseases as other regions.  Usually when disease is a problem in a lawn it is because of improper fertilization or irrigation practices.  One of the turf diseases we do encounter occasionally is Powdery Mildew. 
Powdery Mildew mostly effects bluegrasses and fescues in areas that have received excessive shade or poor air circulation.  The mildew fungus is found on the surface of grass leaves and resembles a white powdery substance. The fungus causes the affected areas to turn yellow and cause lower leaves to die.  Typically we see this disease in the spring or fall when temperatures range in the 60’s and low 70’s. 
If Powdery Mildew is present consider first managing any sources of shade.  You may need to trim trees and bushes to minimize shade and improve air circulation.  Make sure that you implement deep and infrequent watering.  Keep a higher mowing height and fertilize to promote a healthier root system to withstand the disease.  Overseeding the area with a shade tolerant grass can also help. 
If the conditions can’t be improved it might be worth considering an alternate ground cover that is better suited to shade or you may also choose to control Powdery mildew by having a professional lawn care service apply a fungicide to the affected area. 

At Organic Solutions! Inc., we can help diagnose and treat turf diseases such as Powdery Mildew.  If you would like to meet with one of our expert team members to discuss any issues you are having with your turf and go over the options for treatment, please contact us!  
Phone:  208-884-8986
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