Are you seeing brown spots in irregular circular patterns in your lawn? Seeing spotty leopard prints and footprint-like spots in your grass after an early snowstorm or frost conditions? This anomaly is called “chilling injury”, and the reaction occurs with colder temperatures and heat dissipation. This does not happen often, but we witnessed this phenomenon here in New England (November 2020).
As freezing temps crept-in during the week of Halloween 2020 – coupled with well over an inch of snow in some areas – the cool season grasses all across New England were caught off guard. Lawns were still actively growing leading up to the cold and snow and did not have enough time to get acclimated to the colder temperatures and sudden extreme winter conditions.
This is damage to the grass blades from cold temperatures. It is not a fungus or disease, although it appears as one. As colder temperatures set in more consistently, the rest of the lawn continues into dormancy and the color of the “chilling injury” spots should even out with the less green dormant turf.
This “chilling injury” leaves the grass blades damaged. The cause of the leopard-like spots is unknown, but creates some very interesting conversations and theories.
The crowns of the grass should be OK, so these spots should not need extensive repairs. If there are continued warmer temps, the grass may have enough time to recover in the fall. If it doesn’t, the turf should bounce back just fine in the spring.
Read More: https://ag.umass.edu/sites/ag.umass.edu/files/content-files/alerts-messages/chilling_injury_november_2020.pdf