Fall Preparation for Athletic Fields

by NIAAA Sports Turf Committee

Managing athletic fields is a year round process. In fact, there are certain seasonal management practices that need to take place. This article will address various practices that need to be done in the fall. The remaining seasons will be addressed subsequent issues. For example, the fall issue will pertain to winter management practices, the winter issue will concern spring practices, and so forth. You are encouraged to share a copy of this article with your field managers.

This particular issue was longer than space would permit. Therefore, you should refer to the NIAAA’s website at www.niaaa.org and go to “Resource Articles” to obtain a copy of the article in its entirety.

Cool Season Turf

Fall is a primary time of growth for the cool season grasses such as Kentucky bluegrass and perennial ryegrass. It is the time when judicious care will prepare the grass for winter dormancy. Fall is also the time when athletic fields get the most use. Following are a few things you can do to ensure healthy turfgrass as summer wanes and throughout the entire season.

First of all, you need to start preparing your fields in mid to late summer for the fall season. A late July/early August application of a of slow release nitrogen fertilizer at ¾ lb. per 1,000 square feet will provide the turf with nutrients it needs to recover from summer stress without making it too “lush” and susceptible to disease or tear out. In late August/early September you should apply 1 lb. of a combination slow/quick release nitrogen fertilizer to keep grass growing vigorously.

Secondly, monitor your water carefully. In general, you want to water deep and infrequently especially as the temperatures cool down at night. This forces roots to “chase” the water deeper into the soil providing stability. Early fall is a very prolific root growth stage for turfgrass, the more you can do to encourage deep rooting the better your fields will hold up to the traffic. You should also try to go into games with the fields on the dry side. Not so dry that they are hard and dusty but dry enough that the grass does not tear out easily. Moisture management is the key to having good quality turf all season on your fields.

Third, keep a lot of seed on your fields. As practice and play begins in late summer, overseed generously with perennial ryegrass when divots begin to appear. Even putting seed down prior to games and letting the players “cleat” it into the soil will help. You’ll be surprised at how much of this seed germinates and survives. (Dale Getz, CSFM, The Toro Company, Dale.Getz@Toro.com)

Aerificaton

Sports Turf Fields are exposed to many conditions that result in stress of the plants. High traffic areas (soccer goal mouth, between hash marks on football fields, path from dugout to home plate, etc) are exposed to stress caused by soil compaction and poor soil conditions. Core aerification can help manage these problems by loosening the soil makeup and providing a better root zone-growing medium.

Soil compaction reduces plant root growth and will eventually lead to turf decline. Weak, thin turf becomes more susceptible to pest problems like disease, insects and weeks. Compacted soil also prevents nutrients, water, and air from reaching the root zone. The result of heavy traffic causes a loss of pore space in the soil structure, which in turn causes a decrease in oxygen in the soil. This causes significant stress and damage to the plant as all plant root functions require oxygen. The end result is weaker roots, thinning turf, poor and possibly unsafe playing conditions of the field.

Modifying the soil profile through aerification will help relieve soil compaction and aide in restoring the soil pore space. Aerification has many significant benefits and a few disadvantages, however the benefits significantly outweigh the disadvantages.

Benefits
• Relieves soil compaction
• Reduces thatch build-up
• Promotes microbial activity
• Improves water, oxygen and nutrient movement in the soil
• Stimulates root growth
• Helps fertilizer and lime incorporation in the soil
• Aids pesticide and wetting agents incorporation in the soil
• Helps with surface drainage
• Helps establish seed to soil contact when over seeding
• Promotes faster fall recovery of turf from summer stresses
• Softens the field surface for safer playing conditions
• Allows for topdressing soil amendments to improve soil conditions

Disadvantages
• May interfere with Pre-emergent Herbicide performance if done prior to application
• Possible injury under moisture or stress due to improper timing on stressed turf
• Disruption of turf appearance (temporary), aerification plugs can be removed

It is best to aerate in the spring and fall when plant growth is vigorous and the soil moisture is higher. It is beneficial to prepare the turf prior to core aeration for best results. An application of a balance N-P-K fertilizer and adequate moisture will help promote root growth and allow for a quicker recovery. Aerification is an effective cultural practice for the promotion of healthy playing surfaces and should be incorporated into your sports turf management programs. Extremely heavy traffic areas benefit from 2-4 aerations annually. (Michael Harris, Regional Sales Manager LESCO, MHarris@LESCO.com)

Irrigation System “Tune-Ups”

As summer winds down and the various athletic fields are still in high demand, it is a good time to check the actual efficiency of your irrigation system. Constant play, hard surfaces, hot, sunny days, poor soils are factors in fields’ safety. But, if an irrigation system is installed and these problems still persist, it could also be attributed to the actual, physical condition of the system.

If there are brown, consistent circles encompassing the sprinkler heads on the field, a quick “tune-up” could be all that’s required.
• Do a visual working check of the sprinklers. Turn them on and make sure there are no broken parts, leaks, etc.
• Check pressures with a gauge to make sure they are operating at the most efficient pressure. Large droplets mean LOW pressure; small, misting drops mean HIGH pressures. Ask a local distributor and/ or contractor to help if needed.
• Are the sprinklers buried too low? So, when the water comes on, does the stream go directly into the grass or dirt instead of spraying up and over? Are they crooked due to heavy equipment always running over them?
• Are the arcs of the sprinklers adjusted correctly? Are they all rotating? Do they all have nozzles installed? Are they matched for precipitation?

If the turf seems too “wet” in different spots, another simple “tune-up” could help. When systems are not applying water evenly (due to problems mentioned above), dry, hard, brown spots occur. “The Dry Spot Drives the System” is very true. Typically the electric controller gets additional time added to the irrigation run-time, with hopes of making the brown spots turn green. The problem is that the other areas get excessive water, thus making the field wet, unsafe. Furthermore, and promotes disease and pests.
• Check the controller for actual run-times programmed for the different turf areas. Do similar zones have the same run-time?
• In the fall, it can be quite hot and then change overnight. The controller needs to be adjusted to match these climatic changes.
• Some controllers allow zones of sprinklers to increase run-times in percentages. Check to see if this is possible and adjust accordingly.
• If there are “hot spots” (dry turf), try hand watering where necessary until the season ends; specifically if the system cannot be “tuned-up” at this time. Rather than running all the heads on a zone (over-watering) just to hit a specific dry spot.
• Aerate “hot spots” by hand or machine and then apply water. It can now infiltrate into the soil and, hopefully, reach the root structure.
• Check with a local extension agent and/ or university to find out the best possible watering times for your geographic area. Is it night? Morning? Early evening? Of course, it also depends upon time of play on the field…something many have no control over!

Most importantly, find out who the local irrigation distributor is, who the manufacturer’s representatives are, and who the professional contractors and consultants in the area. They can provide invaluable and usually free advice on any of these situations and resolutions. One thing is for sure, efficient irrigation practices can help improve safety and provide year-round playability.