Horticulture Principles and Practices

even surface soil surface for laying the sod. Sod for athletic fields is often delivered in
special large rolls that are laid with the help of special equipment. Light rollers are then
used to roll over the sod to ensure that it makes good contact with the soil. The sod should
be watered immediately and frequently during the next two weeks following installation.
18.7.3 MAINTENANCE
Many athletic fields are in poor condition not because of lack of maintenance inputs, but
because of poor maintenance scheduling. Athletic turf managers should develop and
implement desirable maintenance practices to provide year-round care for the turf, especially
during critical times. Athletic field surfaces are not subjected to uniform traffic.
Certain areas, such as the goal line of a soccer field, are subjected to more intense trampling
and hence more wear and tear than the corner of the sidelines. The management
calendar should take into account the different management needs of these distinct parts
of the playing field. There are two general goals of management of athletic fields—to
promote growth and to prevent pest problems. Cultural practices that promote growth
include watering, fertilizing, mowing, and aerification, while pest protection, weed control,
and insect and disease control are all measures for preventing disease.
Maintenance scheduling may be designed to suit the budget available. It varies
from true professional quality maintenance to a low-budget schedule in which nature is
depended upon for moisture and most maintenance work is done by volunteers. Whatever
the level of maintenance, certain critical maintenance practices are included in a
maintenance schedule. These are mowing, fertilizing, watering, dethatching, aerification,
overseeding, and weed control.
Mowing frequency varies from month to month. Depending on the region, it may be
weekly in February to March and biweekly in April to October. Mowing in December to
January may be done as needed. The turf should be mowed at the appropriate height recommended
for the species. Scalping should be avoided. Mowing directions may be periodically
altered to minimize repeated scalping of the same spot. Rotary mowers cannot
adequately handle mowing heights of less than one inch that many sports fields require.
Fertilizing should be preceded by a soil test. Turfgrass species such as bluegrass
that grow even through winter need to be fertilized all year-round. The rates of application
of fertilizer range from 5 to 7 pounds per 1,000 square feet in Kentucky bluegrass,
to 6 to 9 pounds per 1,000 square feet for Bermuda grass. Zoysiagrass may be fertilized
at the rate of 5 to 6 pounds per 1,000 square feet. The recommended fertilizer ratio is
5-1-4. The sources of fertilizer preferred are the slow-release formulations, such as
Nutralene, IBDU, and poly-S.
Turfgrasses used for southern athletic fields (e.g., Bermuda grass and zoysiagrass)
that produce rhizomes are prone to forming thatch that may build up to between 0.25 to
0.50 inch thick in a short period. When thatch accumulation reaches more than 0.50-inch
mulch, the field should be dethatched. Proper fertilization and mowing, as well as periodic
aerification help to control thatch buildup. Aerification improves aeration of the soil
for rapid decomposition of thatch. High-traffic areas of the field are prone to compaction.
Core aerification helps alleviate soil compaction and also promotes soil drainage and
decomposition of organic matter.
As previously stated, the rule of thumb in watering is to water deeply and
infrequently. During each round of watering, water should be applied to soak the soil to
a depth of about 6 inches. The water should be distributed evenly over the field. To reduce
soil compaction, the field should not be watered at least two days before use.
In areas where grasses go dormant in winter months, athletic fields may be
overseeded with species such as annual ryegrass or perennial ryegrass, to keep the turf
looking green year-round. This activity should be performed after the first frost and at a
rate of about 5 to 10 pounds per 1,000 square feet.
Weed control may be accomplished by using preemergent or postemergent herbicides.
Pest control involves treating the field against weeds and managing insect pests
like white grub, cutworms, and webworms.
18.7 Turf for Athletic Purposes 563