Gray leaf spot is a St. Augustine turf, centipede grass and affects many rye grasses as well. This Fungal disease affects many home owners and clients throughout our Florida properties from Palm Coast to as far south as Oak Hill and out west into Orlando. The fungus is very prevalent during long periods of hot, damp, or humid temperatures. Gray Leaf Spot Fungus is a culprit to cause devastation to the affected turf. The fungal infection produces gray or brownish-yellow lesions with brown and/ or purple edges. During high moisture periods from mother nature such as storms, irrigation, locations with swales or dips in terrain of the lawn, one may notice yellowing known as chlorotic conditions.
This Fungal disease usually first noted in many areas that have moist conditions for extended periods, typically shaded locations under tree foliage, locations near homes or fences of the property. Heavily infected areas will cause a burned appearance from the disease.
Gray Leaf Fungus does best and is most noticeable when air temperatures are 70 – 85ºF, but can reproduce under other environmental factors and temperatures. Gray Leaf Spot Fungus spores germinate and infect the affected turf after sixteen hours of moisture on the leaf surface. The germinated spores penetrate the plant directly or
through openings on the leaves. The onset of the Infection occurs roughly around eight hours after spore germination. High humidity and extended moisture for more than 24 hours will cause conditions to spur major infestations and epidemic to the affected turf.
Gray Leaf Spot Fungus fungus and its spores will remain through cooler months and seasons on infected turf. Wind carries the fungal spores to new locations to infest, as well as rain, storms that deliver precipitation for extended times, irrigation water, and foot traffic from animals, humans, mower blade and equipment. Although this disease can be unsightly, it rarely causes extensive damage to the point of permanently killing an entire lawn.
The best way to keep Gray Leaf Spot Fungus to a minimum is through early identification. Although a lawn spray service can go intervals between applications, it is imperative for any homeowner who notices these locations to reach out to the appropriate lawn spray company who can apply an appropriate fungicide and follow up to help assist during an invasion of this unavoidable fungus.