Iskuvasteita

Iskuvasteita, also known as "snow mold" in English, refers to a group of fungal diseases that affect grass and turf during the winter and early spring months. These fungi thrive in cold, wet, and snow-covered conditions, particularly when grass remains dormant under a thick layer of snow. The term *iskuvasteita* is used in Finnish to describe these fungal infections, which can cause discoloration, dead patches, and overall decline in the health of grass lawns.

The most common types of snow mold include pink snow mold (*Microdochium nivale*, formerly *Fusarium nivale*) and gray snow mold (*Typhula incarnata*). Pink snow mold typically appears as circular patches of pinkish or reddish discoloration on the grass surface, often with a slimy texture. Gray snow mold, on the other hand, forms grayish, cobweb-like fungal growths on the snow surface, which can later spread to the grass blades. Both types can weaken turf, making it more susceptible to additional stress factors like drought, heat, or pests.

Preventing snow mold involves maintaining proper lawn care practices year-round. Keeping grass at an optimal height (around 3–4 inches) before winter, avoiding excessive nitrogen fertilization late in the season, and ensuring good air circulation by trimming trees and shrubs can reduce fungal risk. Removing excess thatch and debris from the lawn also helps minimize moisture buildup, which encourages fungal growth. In severe cases, fungicides may be applied in the fall as a preventive measure.

Once snow mold appears, treatment often involves raking or dethatching the affected areas to remove dead grass and fungal growth. Aerating the soil and overseeding with disease-resistant grass varieties can help restore the lawn’s health. Proper drainage improvements and avoiding heavy foot traffic on affected areas during recovery are also recommended. While snow mold is generally not harmful to humans or pets, it can detract from the appearance of a lawn until the grass recovers in warmer weather.