Identify fungus in the garden by looking for unusual growths that indicate the presence of problems such as powdery mildew on vegetables or fire blight on trees. Garden fungus is often white, brown or yellow.
Powdery mildew is the most common type of garden fungus. It attacks the leaves of vegetables and flowering plants. When it begins, it looks like small white dots or circular patterns, and after it spreads, it looks like a dusting of white powder. Flowering plants are also affected by shotgun fungus, which begins on mulch. Brown splashes on the bases of walls are a symptom of this fungus.
Plythum blight looks like little cotton balls, and it is most visible early in the morning. Common in humid conditions, this lawn fungus often begins on rye grass and spreads to other areas of the garden. Fairy ring fungi appears as circular bands of green and affects all types of grass. Slime mold is an unpleasant yellow mass that looks like vomit.
Fire blight forms on apple or crabapple trees. Watch tree limbs carefully and apply treatment if the limbs turn bright yellow or red. Other types of tree fungus, such as beefsteak fungus or hen of the woods, look like half moon-shaped mushrooms growing from the trunk of the tree.