Cool-season athletic fields.  If you are managing a cool-season field (Kentucky bluegrass, perennial ryegrass, tall fescue or some combination of the above), fall is the ideal time to fertilize.  Ideally, you have already made an application of N in September (at a level up to 1 lb N/1000 sq ft), and you are preparing to make your second and third applications at the same levels in October and November. Giving your cool-season athletic field around 1 lb N/1000 sq ft every 4 weeks during the fall is the best way to optimize turf growth and density now, but also pays big dividends next spring, especially if you have a spring soccer season on this same field.

Another ideal fall strategy on your cool-season sports fields is to aerate your turf.  This requires you to work around the game schedule, so it might not be easy (or even possible).  However, if you have a break in the weekly schedule that allows you to aerate your field by plugging it to at least 3 inches in depth, don’t miss this opportunity.  To the right is a standard hollow-tine coring device, a machine that will leave quite a bit of surface disruption from core removal. If you pull cores, let them air-dry on the surface, then drag them in with a mat or a piece of chain-link fence, and then run your irrigation to melt the remaining cores into the surface.  If you have a sweeper, you might need to run it over the field to pick up the remaining thatchy material from the top of the plugs. 

The next aerator tool shown is a deep, solid-tine aerator that while it does not pull cores, results in very minimal surface disruption while creating channels 8-10 inches deep.  This tool does not greatly impact the playing surface and provides immediate improvements in field drainage simply because it creates thousands of channels for water to move into the soil.  This device can also be fitted with hollow-tines to really maximize the cultivation effects, but its use during the season would be extremely surface disruptive.

For fields that are really being put to the task in terms of excessive use, there is no magic formula for keeping grass on the field under heavy traffic.  However, research is indicating that one strategy is to build a “seed bank” on your cool-season field by regularly seeding the cool-season turfgrass of your choice throughout the season at small amounts on a weekly to bi-weekly basis.  For instance, weekly applications of perennial ryegrass at 1-2 lbs/1000 sq ft will keep something germinating throughout the season, and hopefully keep your players out of the mud.  You have to commit to the regular seeding program because with the traffic on your field, there is no way all the young grass will tolerate the traffic.  However, if you stay on the program, the season will eventually end and at least some of that grass (and some more of the seed you have applied) will establish and provide some coverage for the winter.  Unfortunately, this strategy does not work well with Kentucky bluegrass because it is so much slower to germinate.  Still, it makes more sense to do something than nothing at all.  If you take the frequent seeding approach with Kentucky bluegrass, you will only want to apply it at 1/8 to 1/4 lb/1000 sq ft in your wear areas.

Facing budget constraints? It is often not necessary to manage the entire field.  Since every play basically begins between the hashmarks, it is logical that you concentrate your efforts on this part of the field, typically between the “20s”.  This maximizes your dollars and effort on that most heavily trafficked part of the field. 

Finally, don’t forget your baseball field (or soccer field if it is separate from football).  “Out of season, out of mind” is too often the mistake made on cool-season baseball fields that won’t be used until next spring.  All the elements listed above apply and fall fertilization, cultivation, and renovation by seeding are all very important activities NOW to provide the best playing surface possible next spring. 

Fall bermudagrass strategies.  Bermudagrass managers should be raising their mowing heights now before the first killing frost occurs, and they should ensure that their soil’s P, K and pH levels are appropriate (of course, the only way to know this is to soil test).  It is particularly beneficial to ensure that your soil and plant has adequate potash (K) before it enters dormancy as this nutrient has been shown to be the “anti-freeze” of warm-season grasses. Back off of N applications as you enter mid-October in order to minimize N loss potential.  Consider foliar applications of Fe to promote fall color and winter survival.  I have also had great success over the years recommending a fertilizer commonly thought of as a “row-crop fertilizer” known as Sul-Po-Mag for bermudagrass golf and sports turfs in early-mid fall.  This product (more formally known as potassium magnesium sulfate, containing approximately 20% of each nutrient) is an inexpensive way to promote late season color without a flush of growth.  Apply it at approximately 5 lbs product/1000 sq ft.  And since it contains potassium, it makes an excellent product for your winterizing application of potash.

Now is NOT the time to core aerate bermudagrass sports turfs, although solid-tine aerators can be used in emergency situations when a field is draining so poorly that a cultivation event is warranted.  Save the majority of your coring activities until next May thru July. 

What about turf blankets? Covering your turf has both many advantages as well as disadvantages.  The primary disadvantages are in cost of the blanket for large areas, getting it on and off the field, and keeping it on the field during windy conditions.  The advantages are that covers will extend the growing season by warming the soil, enhance winter survival, and/or provide frost protection.  That late planted cool-season seed just may germinate and establish under a cover this winter, whereas without it, there definitely won’t be much happening until mid-spring (at the earliest) next year.  If you have a spring soccer or baseball season, a turf blanket might be the most important tool at your disposal to getting that turf in its best condition possible as the seasons begin next spring.  And speaking of germination enhancement, this applies to weed seed as well, so be prepared for a potential increase of both grassy and broadleaf weeds under a blanket that might require a herbicide application. Almost any type of cover will improve winter survival by warming the soil, but I have typically found lighter colored covers (those that allow ≥ 50% sunlight to pass) to be the most flexible in use. By allowing light to pass, these covers can also promote spring greening and will still promote winter survival during the coldest part of winter.  However, for those of you with bermudagrass that want to maintain green color for as long as possible during the fall football season a dark colored cover works best and will likely stay a few degrees warmer during the winter than a lighter colored material that passes radiation.  The limitation is that the lack of light will not aid you in spring greening if that is desired.  You can also use temporary cover applications to maintain green bermudagrass color until temperatures are ≤ 25o F (the point at which even most covers can not prevent cold temperature damage to the foliage) if you apply them whenever there is a chance of a significant frost event (the likely temperatures for frost based on my experience are ≤ 37o F).  Note I said “color”, not growth.  As this figure taken on Nov. 17, 2004 in Blacksburg shows, the lack of radiation penetrating the cover seems to prevent chlorophyll degradation (i.e. green color remains), whereas the turf under the lighter colored covers loses color quicker.  Finally, one additional point of caution with covers -- even covered turf can be damaged during extreme cold.  I can remember multiple occasions during my tenure at Misssissippi State University when our university golf course lost their bermudagrass putting greens even with covers in place for the winter.  Turf covers maximize your chances of surviving winter extremes, but the ultimate insulating cover is not a blanket at all – it is straw.  This is the method that will be employed on Virginia Tech’s Worsham Field this winter after the playing season is completed.  A 4 inch depth of wheat straw is a tremendous insulator for cold temperature protection.  Of course, it won’t play well in the spring (!) so it has to be physically removed before any spring sporting events.

Summary.  It’s not too late to take some important steps on your athletic fields in mid-fall, but you need to move soon before the really cold weather arrives.  Some sound management strategies now will carry you through the rest of the fall, and also lead to the best possible playing surface next spring.