As the deep snowpack begins to recede this spring, it is apparent that many golf course playing surfaces suffered from winter related injury. Winter related injury has been reported across much of Eastern and Northern Ontario into Quebec and through Atlantic Canada.
For many courses, the ticking clock for ice cover began in late December, and has continued through mid-April. Some facilities have endured greater than 100 days of continuous ice cover on high value fairways and greens. Turfgrasses and biotypes of the same turfgrass can differ wildly in their susceptibility to ice related damage.
- Certain biotypes of annual bluegrass are susceptible to ice related winterkill after just 45 days. Survival becomes increasingly less likely as ice cover reaches 90 days or more.
- Creeping bentgrass can usually tolerate up to 100-120 days of continuous ice cover. In parts of Eastern Ontario, Quebec and Atlantic Canada, many locations experienced greater than 100 days of ice cover. This has resulted in varying degrees of damage on both annual bluegrass and creeping bentgrass.
As plants break dormancy and soil temperatures rise, carbohydrate reserves are rapidly consumed for stem and shoot development. As a result, root photosynthate reserves diminish, leaving plants prone to future stress and disease pressure. It is important to incorporate a complete fertility program which includes a slow-release nitrogen source. This will limit a rapid flush of top growth and allow for a more balanced use of photosynthetic reserves within the plant. In some places, resurfacing putting greens with sod or re-establishing with seed may be necessary.
Another way to speed recovery is to incorporating a proven plant health product like Signature XTRA Stressgard into your spring program. Research has shown Signature’s unique Stressgard Formulation Technology and fully systemic mode of action delivers numerous plant health benefits including:
- Promotion of plant vigour and cell wall thickening
- Enhancement of root mass and photosynthetic capability
- Stimulation of natural plant defence mechanisms
- Preventative protection against problematic spring diseases such as basal rot anthracnose and cool season Pythium.
|Figure 1. Continuous ice cover began in late-December for many places in Eastern Canada.||Figure 2. Winter related damage on a putting green in Eastern Ontario.||Figure 3. Winter related damage to an annual bluegrass putting green in Southern Ontario.|
Some snow moulds, such as Microdochium patch can develop in the absence of snow cover. Other snow moulds (gray snow mould and speckled snow mould) rely on deep continuous snow cover for infection. These snow moulds get progressively more severe during prolonged snow cover (>100 days).
|Figure 4. Speckled snow mould is commonly observed after extended periods of snow cover.||Figure 5. Microdochium patch can still maintain activity after snow melt.|
Most high rates of fungicide treatments can provide acceptable control of snow mould for greater than 100 days. However, this year, many places in Northern Ontario, Quebec, and parts of Atlantic Canada continue to have deep snow cover for greater than 150 days. This may result in variable snow mould control. As a result much of the fungicide material applied in October - November has already broken down on the leaf tissue. Meaning, turfgrass currently under snow, or recently exposed turf, are no longer protected from your traditional late-fall snow mould application.
To protect your turf from new snow mould infection, or to hasten recovery from existing infection, consider making an application of Interface Stressgard or Trilogy Stressgard. These powerful chemistries are able to provide quick knock down control of snow mould during the Spring. To aid in plant recovery, consider incorporating Signature XTRA Stressgard, the tank mix as this will help promote recovery through improved physiological functions such as chlorophyll production and phoytosythentic efficiency.