You Are Here: Management Updates 2001 Archive April 10, 2001

Date: April 10, 2001
Category: Agronomy
Subject: Winter Injury to Poa annua

Some reports of winter injury to predominantly annual bluegrass greens have been observed from golf superintendents in the New England region. Specifically, after initial spring green-up following warm weather in early spring, the grass may temporarily retain color and vigor followed by a decline in growth (increase wilting tendency and leaf discoloration).

One explanation of these symptoms may be due to differential hardening of annual bluegrass crown tissues. Root growth originates from lower regions of the crown while shoot re-growth occurs from upper portions. Research has shown that annual bluegrass crowns from which roots originate are killed at higher temperature than shoots during freezing stress. These symptoms are most likely due to differential low temperature kill to lower portions of annual bluegrass crowns. Reduced rooting potential (due to differential low temperature kill) along with active shoot growth and transpiration during warming periods may help to explain accelerated wilting and reduced vigor under these conditions.

- Submitted by: Dr. Scott Ebdon