Lately I have frequently been asked how I think the course is overwintering. Although I feel we have overwintered well to this point, there are some issues that have me very concerned.
The most pressing of the concerns is winter desiccation. Desiccation occurs when roots cannot provide enough water to replace what the crowns and shoots loose. We have been without any measurable moisture for far too long. Combine this lack of moisture with high temps an winds and we are approaching a time for concern. With no measurable moisture in any long term forecasts we may have no other option than to start hand watering the greens next week. We will haul water to the greens in our sprayers and apply by hand. This is a time consuming process but the possible benefits make it worth while. I would love to use the irrigation system to supplement the tees, fairways, and rough but that could be at a huge cost to the integrity of the underground piping. The freezing temps would wreak havoc on a charge irrigation system and the costs of repair would far exceed the cost of reseeding any winter damage.
Winter desiccation damage. Notice the wheel tracking. Keeping traffic off these areas is very important.
There are risks to dormant watering that we must be aware of however. Too much supplemental water could provide enough moisture to the plant to catalyze both intracellular and extracellular ice formation. Anytime we experience warm weather coupled with too much available moisture, the crown of the plant runs the risk of hydrating. If this warm weather is followed by a dramatic drop in temperature, there is a risk of ice formation within the plant. The rapid formation of Intracellular ice (ice within the cell) causes mechanical damage to the cell wall and results in cell death. The formation of Extracellular ice (ice between the cell walls) is an equilibrium process meaning that the formation of ice between the cells pulls water from within the cell causing cell desiccation. This desiccation over time can result in a weakened and damaged cell. The correction application of water is very important.
Another issue that concerns me is that these extremely cold stretches we have experienced this year have all been preceded by a short stretch of above-average temperatures. This last arctic blast was proceeded by a couple days in the 50's and 60's and along with those temps came the melting of what little snow cover we had.
The loss of snow cover compounds many issues. The most obvious is that we lose the protective and insulting benefits that snow cover gives us. Snow cover provides good protection to the plant from the extreme cold temperatures as well as the desiccating winter winds. With as little moisture as we have had over the last few seasons, any protection from desiccation is very important.
Fortunately this is not our course but is an example of freezing injury on turfgrass.
Bentgrass has the ability to withstand much lower temperatures than ryegrass so, unlike with desiccation, my initial concern is not for the greens but for the fairways. My level of concern is not alarming at this point because I am not sure that these previous periods of warmth were long enough to cause hydration and it has been so dry. Also the fact that they happened in the dead of winter when the plant was at its highest level of dormancy versus the spring when the plant is preparing to break dormancy will hopefully help our case. On that same note however, it appears we are going to have temperatures well above normal in the near future. If these high temperatures linger long enough and there is sufficient moisture, we could have a problem on our hands.
Preventing winter damage can be very difficulty since our control options are extremely limited. Predicting winter damage is also very difficult. We will do our best to protect everything we can and wait for spring to see the results of what is shaping up to be a difficult winter. Pray for some snow.
