Calls have been coming in from every portion of the region expressing concerns about the possibility of winter injury. Fortunately, consistent snow cover insulates turf and buffers the damaging effects of rapid drops in temperature. In fact, temperature sensors positioned in the soil of greens have demonstrated this effect. While air temperatures have been in single digits or even below zero, soil temperatures at two- and five-inch depths are 20 degrees warmer. Research has demonstrated that Poa annua can tolerate temperatures to -6°F while bentgrass can tolerate lows down to -30°F.
There have also been questions about snow removal from greens. We still have significant winter weather ahead and late winter freeze and thaw cycles can wreak havoc with turf. The cold tolerance of Poa annua can be reduced by five to 10 degrees if turf is exposed to temperatures of 40°F or more for more than eight hours. A thaw followed by a sudden freeze is a recipe for crown hydration damage.
We cannot be absolutely sure how the turf will tolerate the weather we have experienced this winter. Time will tell. It is difficult to not react and do something when there is concern about how the grass is surviving cold, snow and ice. Most golf facilities have prepared very well to protect against the potential for disease as well as insulate for cold with topdressing or geotextile covers. Greens were topdressed (using black sand and/or regular topdressing) and these programs can have positive long-term agronomic effects. Diluting thatch is never a bad decision. In the short term, don’t inflict any additional stress by reacting too soon to the situation.
Source: Keith Happ khapp@usga.org
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