Q: What would be your thoughts on Snow Mold protection for our new soccer field? It is pure Kentucky bluegrass, grown on a 4 inch sand pad. Normally, I wouldn’t worry about it, but I have lush growth from pushing it with 4 lbs N/1000 sq ft since its establishment on September15. Should I use a fungicide; what do others do on their sand fields?-Neric Smith, landscape and turfgrass instructor, Indian Hills CC, Ottumwa, IA
A: Most of the cool season athletic fields that I encounter in the northern United States do not use snow mold control. They may experience some injury from pink and/or gray snow mold, but once the grass begins to grow the damaged areas eventually recover. However, there are always circumstances that may warrant a fungicide application to prevent snow mold.
Iowa and the upper north central region mainly experience pink snow mold and only occasionally see gray snow mold with extended periods of snow cover. Gray snow mold always requires snow cover but pink snow mold can occur with or without snow cover, but it is always more sever under continuous snow cover. If you know you are going to have snow cover, especially wet snow with periods of intermittent melting, then you are likely to have snow mold that will cause some turf injury.
While you are rubbing that crystal ball could you also look me up a few good lottery numbers? Pushing a new field with nitrogen is typical and I do it myself because Kentucky bluegrass establishment is simply so slow; your rate of fall applied N seems fine to me given the circumstances. As you indicated however, it leaves you with plants that may be more lush and susceptible to disease.
Another factor that favors snow mold invasion in your situation arises from the fact that the field is brand new. You might think that a new sand media field may not have much disease inoculum present because thatch and previously infected tissue is not abundant. Even though the field is “new” there certainly could be sufficient spores disbursed in the area to initiate snow mold growth. Once more, the new sand media has probably not had enough time to build up beneficial organisms that keep diseases like pink snow mold in check.
Moving on to the non-agronomic part of the equation you should consider when the field will first be used and how tolerant the field users and administration will be toward some turf loss in the spring. You just spent a considerable amount of time and money to make a beautiful field so a fungicide application may be wise in the first year if you don’t want to be explaining all those pink and white circles on the field in the spring. Severe snow mold has a devastating appearance on the turf during March and April and scarred areas can last into May. So spring sports like soccer, baseball, and softball may again favor a fungicide application. If you won’t be using the field until next fall then it is very likely that any snow mold damage will likely heal after a summer of recovery growth.
Something else to consider are grow blankets and turf covers that act much like snow cover by producing a moist, damp, and shaded environment that favors snow mold. I use Evergreen covers for many projects to establish and protect grass during the fall and winter. They work great to reduce desiccation injury and always help speed establishment and turf recovery.
When I cover areas for the entire winter I usually apply a fungicide like chlorothalonil and iprodione because I know I am creating an environment that favors snow mold. I just completed three native soil baseball infield renovations at local high schools this fall with my students. Like you, we are a little on the lush side going into the winter from pushing them to the max with nitrogen and seeding at a high rate to get them to cover fast.
We did two infields with Kentucky bluegrass, love the grass but hate the establishment rate, and one with turf type tall fescue. I didn’t have the guts to do an infield with tall fescue until Rich Watson from the New Jersey STMA Chapter sent me pictures of his success with a tall fescue infield. I’d like to hear more about your good and bad experiences with tall fescue for baseball infields.
My situation was a sand amended practice field with no automatic irrigation so water may be lacking when the summer ball season ends and all the help leaves. The turf covers were crucial during the establishment and grow-in process. The covers were placed in September right after seeding and they helped retain moisture and modify temperature for rapid establishment. I also had to walk on the field every day for some hand watering and the covers kept me nicely out of the wet and sticky soil. Areas that were not covered simply didn’t fill in during the fall.
OK, Doc, get back to the subject! My point is for under $150 I can provide snow mold protection on three baseball infields that need to be ready for play by late April and the coaches don’t want to hear excuses no matter what letters I put before my name.
To recap on the snow mold fungicide question: most don’t, some do, so rub your crystal ball but don’t cry boo hoo.