Barefoot in the Park
The goal of any park agency is to build and maintain parks and facilities that are clean, well kept and inviting. One of the best ways to meet this mission is to provide green, clean turf on your sports fields, adjacent to trails and common areas and around playgrounds and pavilions.
Of course, maintaining healthy turf is easier said than done, seemingly more magic and slight-of-hand than expertise.
To help you pull the rabbit from the hat, here are some critical elements to include (or at least consider) when you rework your turf maintenance plan.
Turf Choice
Crucial to any turf maintenance program is determining the best turf choice for each specific area, particular use and appropriate climate. Grass-species selection is typically not the same throughout the whole park, and blends or combinations of several varieties are recommended.
Seasonal grasses are categorized based on their growth cycle. Cool-season grasses (sod or seed) have their best growth periods (fertilizing and seeding) in the spring and fall. During the cool winter season, they establish a good root system to make it through the hot summer. In August, cool-season grasses turn dry and brown and then come back in September. Warm-season grasses (sprigs or plugs) are typically more productive on problem soils and often require less irrigation.
What you choose to use on athletic fields may not be what you choose for less-trafficked areas. As an example, perennial ryegrass is a lower-maintenance turf often used for sports fields. It is also quick to establish and very good for spot repair. You may say, “Well, it doesn’t look as good as Kentucky bluegrass.” But remember, it is hardy for heavily-trafficked areas such as the middle of soccer fields and in baseball outfields where people stand.
Kentucky bluegrass, on the other hand, has a thick, dark-green canopy, grows in a rhyzomatic pattern, and is not as draught-tolerant as ryegrass. More beautiful than, but not as robust as perennial ryegrass, Kentucky bluegrass may be a good choice for less-trafficked areas. Often, annual ryegrass is used in conjunction with Kentucky bluegrass to increase the hardiness of the turf.
Bermuda grass, yet another option, is relatively high maintenance, requiring monthly, and often synthetic, fertilization. Bermuda grass, as with bluegrass, has rhyzome, stolon runners that are aggressive and take over other areas and, after the first frost, early in October, it turns brown. Some park services are now experimenting with seeding Bermuda grass fields with annual ryegrass in October to give the fields a green cover over the winter. The ryegrass dies off in the spring, in time for the Bermuda grass to have its season.
When it’s not possible to keep grass on athletic fields, more and more recreational parks are going to artificial turf, a woven plastic combined with crumb-rubber and sand that gives a spongy effect.
If the area you are working to improve is in the shade (where turf typically struggles to grow), consider another kind of groundcover (shade-loving plants that spread naturally). Your ultimate groundcover choice will depend on location, situation and intended use of the area, but professionals most often rely on native (naturally-occurring) groundcover. So, don’t be afraid to plant what already works well in your area.
It’s a Science!
A good turf maintenance program applies well-researched Best Maintenance Practices (BMPs) to established turf grasses in parks and sports fields using methods that are not only cost-effective but also environmentally conscious.
Methods include:
1. Careful soil monitoring and watering practices
2. Aeration before putting materials down, both in the spring and the fall
3. Fertilization after aeration
4. Top-dressing
5. Over–seeding
6. Weed, insect and disease control
Sound simple? It’s not! It’s a complex and scientific body of knowledge that includes compliance with Environmental Protection Agency (EPA) regulations.
Soil and Moisture Monitoring
“First, take a soil sample for testing and pH analysis,” urges Mark Plourde, Fairfax County Park Authority Pest Controller, responsible for athletic field maintenance. “The key to having good turf is having a good soil profile. The soil has to be accessible to nutrients in both established areas and when constructing a turf area for an athletic field.”
Adria Bordas, the Virginia Horticulture Cooperative Extension Agent in Fairfax County, agrees: “Always do a soil test. It can be done very inexpensively through your local Cooperative Extension Service. I recommend a soil test to establish a baseline for different soil textures.”
Most state universities—such as Virginia Tech University—have labs that will analyze the soil. The state Cooperative Extension Office will give you recommendations to amend the soil. Follow the amended-soil recommendations by the lab.
Moisture is monitored in a like manner using a soil probe similar to an aeration tine. Check how far down into the soil profile the soil moisture registers, and set your irrigation cycles appropriately. “We have 100 acres of our 300 that employ an underground irrigation system. The system uses special sprinkler heads, a pump house, and is controlled remotely through a computer using a particular software program. Those 100 acres get more attention. We have to mark the special heads before employing some turf maintenance methods.”
Aerate, Aerate, Aerate
Aeration uses a combination of aerating tools such as the hollow-tine aerator (core aeration), shatter-tine, sport-tine and solid-tine equipment to pierce the soil and any accumulated thatch with holes. The core aeration method produces a more porous soil by removing dirt and grass cores so materials such as air, water and fertilizer get closer to the root system. Other piercing methods relieve compaction.
“Because of the large amount of clay in mid-Atlantic region soils,” explains Bordas, “parks and recreation areas have to concentrate on relieving compaction. The soil in sightseeing areas with heavy foot traffic, such as on the National Mall or at Mount Vernon, must be aerated on a regular basis.” In Fairfax County, the best times to aerate are in late February/March/April, late June and late August. “Aerate as often as possible, customizing the schedule around athletic field use,” recommends Bordas and Plourde.
Fertilize
“As a basic program,” explains Plourde, “Fairfax County puts down an organic fertilizer in early spring, late February or early March, after aeration. Something with a limited amount of nitrogen, like a 10-10-10.” That’s the NPK nutrient ratio of the fertilizer—in other words, 10 percent nitrogen to promote top growth, 10 percent phosphorous to promote root growth and 10 percent potassium to support the total plant. Plourde goes on to say, “Since the turf is already growing, we don’t want the top to grow faster than the roots because that creates a shallow root zone. The turf and root system ratio should be 50/50.” In the fall, you may wish to consider three applications of fertilizer including synthetics with an NPK of 18-5-9 or 24-6-12 that provide a slow release of nitrogen over the winter.
Because Fairfax County has a mostly clay and micropore soil system—big areas impenetrable for roots or nutrients and then big pockets of open space—the nutrients cannot get through this type of soil compared to sand, where everything flows right through it,” explains Plourde. “We are experimenting with a 5-4-5 fertilizer combination that is an unprocessed slow-release organic material to give not only more nutrients to the soil, but also more time for the soil to give the nutrients to the plants.”
Top-dressing
Top-dressing is the practice of layering local material, sand, clay or topsoil over the turf, providing an additional rich dimension to the soil profile. Frequently applied after aeration or special deep-drilling processes, the top-dressing material is incorporated into the drilled holes and soil with a top-dresser spreader and is then dragged in. This prepares the soil for seeding and can be used to ensure fields are appropriately level.
Over-seeding
Fall (especially September) is a good time for seeding in combination with aerating and fertilizing. “We seed later in the season—late November or early December—because Fairfax County does not close the athletic fields before early December,” says Plourde. “We want to avoid any traffic on newly-seeded fields. We use an aerator/seeder. Then crews install natural-fiber blankets over the fields that stay out over the winter to incubate the seeds. You can fertilize right over the top of the blanket. A light layer of snow helps the seed to germinate by slowly irrigating the turf when it melts.”
Outside field edges are seeded once. Fields that get excessive wear, such as the centers of soccer fields and baseball outfields, are often seeded twice, also known as over-seeding.
Weed, Insect and Disease Control
Typically, turf pests can be controlled with good turf cultural practices such as monitoring for pests, checking thresholds of damage, analyzing plant health, putting down preventive fungicide rather than curative pesticides and using mechanical/manual means of removal. Incorporating an Integrative Pest Management program (IPM) customized for the site provides a safer and often less costly option for effective pest management, resulting in less use of pesticides.
Organic fertilizer and cultural practices, including aeration, reseeding and over-seeding, mowing and top-dressing, can reduce the need for chemical pesticides. Maintaining a good soil pH with a quality organic fertilizer provides weed reduction in athletic fields and in areas of heavy foot traffic, thus eliminating the need to spray pesticides or fungicides and keeping the fields open for public use.
When turf is healthier and not waterlogged, it is harder for fungus such as powdery mildew or snow mold to attack the turf. These fungi are controlled with cultural practices rather than with fungicides. IPM is applied not only to turf but also to trees and shrubs, monitoring for insects and manually removing nests.
Timely mowing is another cultural control of weeds and insects. Perennial ryegrass is typically mowed to a height of 2½ inches once a week, Kentucky bluegrass to1-1½ inches once a week and Bermuda grass to ½ inch three times a week. Remember, never cut more than 1/3 of the grass canopy.
What about grass trimming? For a finished look, edge next to any paved surfaces. Better yet, create mow strips such as bluestone dust along the pavement or fence line to eliminate the need for weed eating, and provide access for the mowers!
Chemical Control as a Last Resort
Although cultural practices reduce the use of pesticides, judicious chemical use is still necessary and appropriate. In Virginia, insecticides are used for white grubs and areas of full sun that provide a breeding ground for Japanese beetles that love to eat in the root zone. Fungicide, insecticide and broad-leaf weed control applications are scheduled every several years. Follow EPA regulations for pesticides. Each state has additional regulations. Your park operations procedures may have more requirements than the EPA, but they may not have fewer.
Words of Wisdom
Along with a good turf maintenance plan, Plourde and Bordas leave us with these insights that promise your park a green and welcoming appeal!
1. Use your Cooperative Extension System for knowledge, training and support.
2. Test the soil … test the soil … test the soil.
3. Create a mix and balance of positive aspects of several varieties for a hearty turf—never have a monoculture of grasses.
4. Plan precise timing of aeration, fertilization, seeding and pesticide application—it is critical to successful turf maintenance.
5. Cut no more than 1/3 of the canopy of the turf when mowing.
6. Consider synthetic turf or native groundcover as alternatives in problem areas.
Judith Harroun-Lord is a freelance writer as well as technical writer and editor in the Washington, D.C., metropolitan area. You can reach her via e-mail at eqw@shentel.net
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The Cooperative Extension System
Some use of pesticides will be necessary in your turf maintenance program, even though much progress has been made meeting federal pesticide-reduction goals by applying cultural, mechanical and chemical strategies.
The EPA establishes federal pesticide policy and regulation. The U.S. Department of Agriculture (USDA) is responsible for research, training and education through state Departments of Agriculture and state Cooperative Extension Systems.
Certification is required for federal and state government employees to spray pesticides. Certifications include those for Registered Technician and Certified Pesticide Applicator. Categories of certification for Certified Pesticide Applicators are Turf/Tree/and Shrub (Ornamental), Forestry and Right-of-way. Training and certification testing are provided through your state Department of Agriculture Cooperative Extension System.
The Cooperative Extension System is a nationwide, non-credit educational network consisting of more than 100 colleges and universities, comprising the nation’s Land-Grant University System. A land-grant college or university is an institution that has been designated by its state legislature or Congress to receive unique federal support.[1]
The federal partner of the Cooperative Extension System is the USDA Cooperative State Research, Education and Extension Service (CSREES), an agency within the USDA that helps fund the actual research, education and extension at the state and local levels, and provides program leadership in these areas.[2]
Every U.S. state and territory has Cooperative Extension Offices both at the associated land-grant university and within a network of local or regional offices. These offices provide useful, practical and research-based information, including training and certification to communities of all sizes.[3]
Mark Plourde, Fairfax County Park Authority Pest Controller, and responsible for athletic-field maintenance, carries a Virginia Certified Pesticide Applicators license that includes certification in the following categories: Forestry, Ornamental, Turf and Right-of-way. “Training criteria for a Registered Technician,” explains Plourde, “includes 40 hours of training—20 hours of classroom training and 20 hours of field training with a Certified Pesticide Applicator. The Registered Technician is qualified to spray general-use pesticides and may spray for restricted-use pesticides when supervised by a Certified Pesticide Applicator.”
[1] USDA CSREES website
[2] USDA CSREES website
[3] USDA CSREES website