Modern day turf managers rely more and more on chemicals to solve their problems. When effective fungicides were first introduced they were used on an as needed basis. When a disease showed up, the chemical was applied. Later, preventative maintenance was the norm, with applications being made every two to four weeks on greens and tees. Most fairway applications were still made on an as needed basis. Today, the trend seems to be weekly applications on greens, tees and fairways. In some circles the bragging rights seem to revolve around which superintendent has the most sprayers in his maintenance building and how often he uses them.
The first problem with this approach is the damage that is being done to the microbial population in the soil. Whenever a chemical is applied, it will have the desired effect on the pathogen that is being targeted. There is no chemical made however, that can single out the targeted pathogen for destruction and not do any damage to other soil organisms. Most chemicals wipe out a wide range of soil microbes. Some of them are pathogenic and some are beneficial. Continual applications of chemicals will not sterilize the soil. Mother Nature abhors a vacuum. She will find something else to fill the void left by the organisms that were depleted by the chemical applications. Following a chemical application, the total microbial population will rapidly bounce back, but the types of organisms that are present may be somewhat different than before. They may or may not be to our liking.
The second problem with weekly chemical applications is what it does to the normal fertility program. Because the turf is being sprayed on a weekly basis the normal line of reasoning is to make liquid fertilizer applications along with the chemical applications. The thought being that this will eliminate the need to apply granular fertilizers, thereby reducing the number of times it is necessary to be on the turf. The big problem with this approach is that the liquid fertilizers being applied along with the chemicals are doing nothing to feed the soil microbes. These fertilizers are in forms that are directly available to the plants and totally bypass the soil microbes. Beneficial soil microbes have the ability to reproduce much more rapidly than pathogens if they have a food source. However, if they are being wiped out by the chemical applications and they do not have an adequate food source, the pathogens are able to reproduce more rapidly. That is why we have times when the disease pressure is so great that some chemicals that are supposed to give two to three week control are only able to suppress the diseases for two or three days. At that point, the pathogens are reproducing more rapidly than the beneficial organisms and it becomes necessary to make more frequent chemical applications to save the turf.
The food source for soil microbes is carbon and the richest source of carbon is amino acids. If enough amino acids are available on a regular basis to the beneficial soil microbes they will be able to reproduce much more rapidly than the pathogens. The beneficial microbes will then be able to hold the pathogens in check for longer periods of time.
Most spray programs include some liquid amino acid supplements, but these products do not come anywhere close to supplying the amount of amino acids the soil microbes require. Normally, the soil microbes require between 50 to 200 times more amino acids than can be applied from liquid spray programs. The only real way to meet the needs of the soil microbes is to make regular applications of a granular organic product like Nature Safe that has high levels of amino acids. Most pure organic Nature Safe products contain in excess of 50% amino acids that will supply the soil with over six pounds of amino acids per thousand square feet for every pound of nitrogen that is applied. The best liquid amino acid supplements will only be able to supply less than two ounces of actual amino acids per thousand square feet per month even if they are applied weekly.
Certainly, the use of chemicals and liquid fertilizers, including amino acid supplements, is very beneficial to the turf and they should not be eliminated. However, relying on them totally and failing to feed the soil microbes is like removing one of the legs of a three legged stool and trying to sit on it. If you’re good you may be able to balance yourself quite well, but your position will always be somewhat precarious. The third leg must be in place for stability. In the case of a solid turf maintenance program, the third leg of the stool is the soil microbes. They must be fed adequately to produce a healthy soil and a solid program and no other product can match the food value for the microbes that is found in a bag of Nature Safe.