Cultivating Cold-Weather Turf
By Stephen C. Brown
Contrary to conventional logic, establishing and managing recreational turf for parks, playgrounds, and sports fields is very easy in Alaska. With relatively few diseases and insects to deal with, turf managers in the Last Frontier have an easier job than their Lower 48 counterparts. The key is establishing and managing turf for Alaska-specific conditions.
Choosing the right grass variety for a specific location is one of the most important decisions you’ll make when establishing a new recreational field. The most important considerations in selecting the proper grass are cold tolerance, drought tolerance, rate of establishment, spring green-up, and the amount of sunlight the site will receive.
A Tale Of Two Turf Grasses
The two most commonly grown recreational-turf grasses in Alaska are Kentucky bluegrass and red fescue. Kentucky bluegrass is considered the prettier and hardier of the two grasses by many. It can also handle high traffic. For this reason, it is the grass of choice for baseball, soccer, and football fields in Alaska. However, it does have a high fertility requirement and needs sunny locations.
There are many Kentucky bluegrass varieties to choose from, but it is important to select a very cold-tolerant cultivar. The most highly recommended variety for Alaska is Nugget. Unfortunately, the demand for this variety often outstrips the seed supply. Other suitable varieties include Merion, Park, and Fylking.
Red fescue is more tolerant of shade than Kentucky bluegrass. Red fescue is also extremely cold-tolerant. This grass requires less fertilization than Kentucky bluegrass and is moderately drought-resistant. Red fescue is a good conservation grass for stabilizing slopes, and is relatively inexpensive compared to Kentucky bluegrass. The drawback of growing red fescue is that it develops thatch easily and is less resistant to high traffic. Red fescue needs well-drained soils; it can be grown in some gravelly situations without applying topsoil.
The two best varieties of red fescue for Alaska are Arctared and Boreal. Arctared is the most cold-tolerant and can be used throughout the state. Boreal is slightly less cold-tolerant and should not be used south of the Alaska Range Mountains. Both Arctared and Boreal are native Alaskan grasses.
The best time to establish recreational turf in Alaska is when soil temperatures are warm (55 F or higher) and when enough time is left in the summer for a root system to become well-established. This will usually be from the beginning of June to mid-July. Areas that do not have access to irrigation are sometimes successfully planted in August to take advantage of seasonal moisture patterns, but it is still a gamble against an early winter.
Regardless of the grass variety(s) you choose, always buy fresh grass seed for establishing a new field. The germination rate of seed will decline each year. Seed Kentucky bluegrass fields at a rate of 2.5 to 3 pounds of seed per 1,000 square feet. Because red fescue has a larger seed, it needs to be sown at a rate of 3.5 to 4 pounds per 1,000 square feet. Kentucky bluegrass and red fescue mixtures are sown based upon the predominant grass. For either variety, it never hurts to apply more than the recommended rate. Up to 50 percent more is acceptable.
To obtain the most uniform seed coverage, sow half the seed in one direction. Then apply the remaining half at a 90-degree angle to the first application. Save several pounds of seed to fix any thin areas that may occur. After sowing the seed, lightly rake or drag it into the top quarter-inch of soil and then roll with a turf roller.
It is important to keep the soil moist until the seeds germinate. Several light irrigations per day are ideal. Weed-free straw or open-mesh burlap can be used to help retain surface moisture. If straw is used, be absolutely sure it comes from a weed-free source, or you may be planting weeds in the turf. The straw or open burlap does not need to be removed once the seeds germinate.
Red fescue seed will germinate in seven to 14 days, while Kentucky bluegrass may take up to a month. Obviously, for areas planted in August, red fescue has a greater chance of successfully becoming established before winter than Kentucky bluegrass does. Once the grass germinates, you can reduce the watering.
Tending To Details
Proper fertilization is very important for any recreational turf in Alaska. At a minimum, turf fields should be fertilized in late May and again in late July. It is recommended that the turf be fertilized with 22-11-11 at a rate of 5 pounds per 1,000 square feet.
A soil test is required to determine the pH level. Most, though not all, soils will be on the acidic side of the scale. If they are too acidic for the type(s) of grass you are growing, the pH will need to be raised using lime. Contact your local University of Alaska Fairbanks Cooperative Extension Service Agent to get a recommendation specific to your soil test results.
If you need to lime your turf, prilled (pelletized) lime distributed with a rotary spreader is usually more convenient and less messy to apply than powdered lime. Agricultural lime will supply calcium to the turf while dolomitic lime supplies calcium and magnesium. Don’t use hydrated or “builders” lime since that material is caustic.
Proper fertilization, mowing, and watering will go a long way towards controlling weeds in turf. If broadleaf weeds (non-grasslike weeds) become an excessive problem in a field, selective herbicides will target the weeds and not harm the grass. These herbicides usually contain chemicals such as 2,4-D, MCPA, MCPP, dicamba and/or triclopyr. They are usually labeled as broadleaf weed-control products.
Herbicides can be purchased in both liquid and granulated forms. Fertilizers sold as “feed and weed” products usually contain broadleaf weed-control herbicides. Be extremely careful when using these products around ornamental shrubbery and flower beds.
Weed inhibitors are a special type of herbicide that is applied early in the spring to prevent the germination of weed seeds. To be effective, though, they must be applied at the right time and according to the label.
When applying herbicides, it is critical to read and follow the label and wear the appropriate protective equipment. Never store unused herbicides in unmarked or improperly marked containers, and always store them in places inaccessible to children and pets. It is also a good idea to contact the Alaska Department of Environmental Conservation to find out the most current regulations regarding herbicide applications.
Moss is a major turf problem throughout Southeast Alaska and coastal areas. Moss thrives in moist, cool conditions with little or no presence of soil nutrients and low soil pH. In order to prevent moss from taking over an area, it is important to create conditions that favor the grass rather than the moss. Good drainage, proper fertilization, adequate light, proper pH, reduced soil compaction, and proper varieties all contribute to establishing turf that resists moss growth.
In a situation where moss is already beginning to take over, it is important to achieve the conditions necessary for promoting healthy turf before focusing on moss destruction. Once a healthy turf environment is established, there are a number of products that are commercially available to kill moss. The only way these moss killers will be effective long-term is by maintaining the prescribed turf-favoring conditions.
Stephen C. Brown, Ph.D., is a Mat-Su/Copper River/Anchorage District Horticulture Agent for the University of Alaska Fairbanks. Reach him at firstname.lastname@example.org.