Spring Winterkill

Turf loss during wintertime, or winterkill, can be caused by several issues:

• Crown Hydration. Crown hydration takes place in the latter part of winter. Typically, Poa hydrates under high moisture conditions and crown hydration strikes when the moisture forms ice and ruptures Poa cells with a rapid drop in temperature. Remaining dormant longer allows Creeping bentgrass to be less susceptible to damage from crown hydration. To remove excess surface moisture, to be sure to solid tine aerate.
• Winter Desiccation. Turf without snow cover or other protection is exposed to cold, dry wind and low temperatures, which basically freeze-dries it. Areas of elevated turf are extremely susceptible to damage and this applies to creeping bentgrass and Poa.
• Direct Low Temperature. Warm-season grasses more susceptible to direct low-temperature damage when there is a rapid temperature decline.
• Ice Sheets – One of the main reasons for concern of ice sheets is that ice accumulation on turfgrass for prolonged periods can lead to terminal levels of carbon dioxide. Creeping bentgrass will survive 150+ days with ice accumulation; while Poa will survive 75+ days. There are multiple materials you can choose to aid in melting ice:  black sand, dark, organic fertilizers and even sunflower seeds. Solid tine aeriate to release gas accumulations.
• Snow mold – Fungal pathogens, like pink and gray snow mold, can cause winter injury. Apply preventative and curative fungicide applications to fight this cause.

While winterkill can cause serious injury to turfgrass, there are steps to take to prevent and recover from it.