Tips From The Pros

ORGANIC ATHLETIC TURF MANAGEMENT

In recent years, “organic” turfgrass management has come on to the scene with several companies offering products and services for well-intentioned land care managers. Lots of pie-in-the-sky, undefined terms like “sustainable” and “harmony” in some of these programs in my opinion, and as I discuss below, these feel-good approaches may have damaging effects. The telltale sign is when they claim lawns and well-maintained turfgrasses are bad for our environment, a claim that is provably wrong. There are national and state certification programs that establish food crops as organic, but you can’t just assume these food-crop principles will transfer over and work for land care. It’s a further reach to apply a food-crop standard to the crop of turfgrass management, and still harder to apply these standards and practices to athletic field turfgrass management.

Synthetic pesticides and fertilizers were partly designed to reduce the labor and other costs associated with crop management and they have done this very well from this narrow standpoint. As such, any shift to a turfgrass management program that reduces or even tries to eliminate all applied synthetic products (a turfgrass vegan?) will likely be more labor and capital expensive. This is an important consideration, especially in operations with larger scopes.

But these limitations don’t mean we can’t design a turfgrass management program that both fits the health, safety, performance and aesthetic needs of our natural grass athletic fields, maximizes the many environmental benefits to maintaining a healthy stand of turfgrass, and minimizes the unavoidable environmental impacts when we decide to manage any land for human purposes.

A full discussion of the decision criteria involved in a move to a more “organic” field maintenance program is well beyond the scope of this blog. However, there are a few points of interest that can be teased out as a primer for those considering such a move. Each region and even each venue has different needs and regulations that must be followed. As such, a careful and considered approach is best. For every facility, a more environmentally friendly turfgrass maintenance program must be built in stages, relying on science and research as much as possible along with small-scale trial-and-error.

First off, a definition. “Organic”, in a general sense, can be said to mean having derived from an organism, or a living thing-plant or animal. In a more technical-chemistry sense, it basically means the chemical contains carbon (C). In this light, an organic compound may or may not be harmful to human health. Its simple chemical definition as organic or inorganic says almost nothing about its potential impacts to humans, wildlife and environments. For example, water is an inorganic chemical. It falls from the sky. You cannot manage a “chemical free” stand of turfgrass. No part of earth is chemical free. DDT was rightly banned worldwide for its dangers to humans, wildlife and the environment and it is an organic compound. So we have to be careful with terms.

Pesticides

Maybe the first thing people think of when they consider organic turfgrass management is to reduce or eliminate synthetic pesticide use, generally in terms of fungicides, insecticides and herbicides. Managing almost any crop involves disturbing the soil and bringing in foreign species to the area (the turfgrasses we use). You create a new host and environment for exotic pathogens, insects and plants (weeds). All this has to be managed. In my opinion, careful pesticide use within a well-designed IPM program is the best approach.

My advice? Educate yourself on, and institute a sound Integrated Pest Management (IPM) program. This is your best bet for a proven way to manage pests in your turfgrass playing fields and surrounds that builds a specific pest management decision mechanism based on practical and defined economic thresholds. An all-out ban on synthetic pesticide use without a mechanism for their use to avoid damage beyond pre-agreed upon thresholds of damage is short-sided and not based on reason. Nature will eventually make an all-out ban look foolish, in my opinion. That said, I believe there are important issues involved with pesticide over-use and misuse in turfgrass management that must be addressed. The best way to minimize or even virtually eliminate pesticide use is through trained and educated turfgrass science and a robust program of knowledgeable scouting for pests and early treatment implementation, before the pests get established.

A good IPM plan takes time to develop. It should be in agreement with any organizational protocols and policies. It involves increased scouting for pests and a set of economic damage thresholds that spur certain actions. It requires a good understanding of the host-environment-pest relationships and managing genetic resistance to the products. Field managers that really wholly on one broad-spectrum fungicide, insecticide or even herbicide will end up applying more total product unnecessarily, and increase the chances of pest resistance to their pesticides. When pesticides are indicated, they must be handled and applied by well-trained and educated personal meeting any federal, state or local mandates. The correct products at the correct amounts, applied in the correct way are key to minimizing any potential health impacts and waste. Another key is to keep up to date on new chemistries and products available.

Compost Teas. Recent years have seen a rise in the development and use of commercially available or “homebrew” composted teas that are applied to the turfgrass to with the intention of improving long-term soil health and reducing the amount of required nitrogen that is applied. The basic idea is to begin with some kind of organic “malt” and essentially culture a large batch of “tea” that is full of these beneficial microorganisms and perhaps their beneficial side-compounds. Some manufacturers have available the full set up with bio-chamber and starter products for making your own teas. Some turfgrass managers have just done it on their own, using locally available organic waste like leaves and organic litter for the starter “malt”. The finished tea is removed from the ‘fermentation’ chamber after some time and sprayed onto the turfgrass stand regularly.

One consideration is any possible risks in regularly brewing large batches of bacteria in an on-site chamber. I would assume that cleanliness and good sanitation principles are required, and I would want to make sure I am not accidently brewing up bacteria that could pose a threat to humans, like Salmonella for example. I’m sure the better services and set-ups have addressed this.

The difficult thing to asses with compost teas is the efficacy. Do they really work? Research is quite mixed on the subject as there are a myriad of variables to work out. For example, each batch of tea has to be genetically assayed to determine the exact population of microbes in that batch in order to proceed with scientific evaluations on efficacy and side effects, if any. As a result, we have little scientific consensus to work with when it comes to compost teas on turfgrass. But that does not necessarily mean they are not effective. I can remember when “bio-stimulants” were seen with skepticism by researchers many years ago. From what I have seen, the science is now catching up with those who had espoused the virtues of bio-stimulants all those years ago. So maybe someday we will see the same with compost teas, but I consider them something to experiment with informally on a small scale in a careful program developed for their use.

Another possible issue to consider when using traditional organic products can be the smell. You have to apply relatively large amounts and some products may give off an unpleasant smell for a few days after applications.

Operational cost comparison. Converting any area of managed turfgrass into an all organic fertilizer program will increase labor and material cost of the fertility and field management program. Exactly how much depends on the operation. But material costs alone can easily double on a per acre average and could be tripled in order to meet trafficked turfgrass nitrogen requirements. Cultivation procedures (e.g. core aeration) will need to be increased as the required nitrogen will only come from the breakdown or mineralization of the organic nitrogen in the soil organic material. And this can only occur in an oxygenated soil dependably above 50F soil temperature. Fields and turfgrass areas will need to be monitored more closely in an all-organic fertilizer program, and this also increase costs. Soil phosphorus levels will need to be monitored closely in an all-natural organic program.

While it depends on which type of true-organic fertilizer source used, it is commonly accepted that true- organic fertilizers are more expensive than synthetic fertilizers on a cost per pound of nitrogen applied comparison. The following is just one example of a cost comparison using products locally available. One product that meets the IFM criteria was chosen for the example. The example is given to show relative sourcing costs and to show how to properly compare fertilizer material costs.

Turf Tips 101: Integrated Fertility Management (IFM)

While I do believe you may be able to manage a lawn fertility needs through the exclusive use of organic fertilizers (according to food crop fertilizer definitions), it is very difficult if not impossible to manage a high-traffic natural grass athletic field and its fertility requirements this way. Simply put, you’ll likely have to add a large amount of organic fertilizer into your budget to meet the higher nitrogen requirements that have been documented on higher traffic turfgrasses. Additionally, you may be applying far more phosphorus than needed which comes along for the ride in most organic products. True organic fertilizers usually have 10% or less nitrogen by weight. The dried poultry waste (DPW) products and bat guano may come closest to 10% N. Most fall far short of that in the 2-5% range. If you need say 5 lbs. N/1,000 sq. ft./year on your turfgrass, that’s a lot of organic fertilizer to get there. It may mean a lot more phosphorus is being applied than you need.

Nitrogen is an essential element needed in the greatest quantities by turfgrass, and almost all other plants. It can only be taken up by the plant in one of two forms, the nitrate form (NO3-) or the ammonium (NH4+ form). Whether organic or synthetic sources of nitrogen are used, all fertilizers added to the soil must undergo the important process of nitrification in order for the plant to be able to gain use from it. In soils, this process is carried out by two bacteria in a two-step process. Eliminating synthetic fertilizer sources does not eliminate the turfgrass’ need for an adequate level of nitrate nitrogen. However, too much soil nitrate-nitrogen is prone to leaching and surface run-off in certain conditions. Organic fertilizers reduce the risk of this as the nitrification process and the subsequent release of nitrates in the soil occurs at a slower rate generally. The challenge for the turf manager is to balance the nitrate or ‘available’ soil nitrogen through judicious applications of supplemental nitrogen sources. Too much and the grass grows lush and is prone to a number of maladies, and the soil microbial environment grows out of balance. Too little soil ‘available’ nitrogen and the microbes will outcompete the turf for it and the result is a turfgrass stand deficient in nitrogen, stunting growth and development.

Trying to solve this conundrum of nitrogen, fertilizer manufacturers have developed products that may start with a traditionally organic fertilizer like dried poultry waste (DPW) and fortify it by adding in a high-nitrogen synthetic organic compound. These “fortified organic” fertilizers are sometimes referred to as “bridge” fertilizers because they intend to “bridge the gap” between traditional synthetic fertilizers and the relatively low nitrogen organic fertilizers. They can act in the soil almost like a purely organic fertilizer, except the fortified version balances out some of the problems with the relatively “low and slow” nitrogen provision in the soil seen in most non-fortified organic fertilizers. The fortified nitrogen sources on some of the better products are actually long and medium chain organic molecules that release nitrogen on the soil by bacterial conversion almost the same way organic nitrogen is converted. These organic bride fertilizers can make up the lost ground in nitrogen needs for higher trafficked athletic turfgrasses. One possible down side to these organic bridge fertilizers is their relatively high costs, but they are one way to go more organic on your sports fields.

Resources of the Month

For lower intensity maintenance turfgrasses like lawns, a switch to a pesticide-free management program can be done according to this Cornell University Turfgrass bulletin.

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“A beautiful lawn doesn’t happen by itself”. – Author unknown