Bekah Rottenberg 2003 Brown University

Alternatives to Pesticides: Practices and "Successful" Courses

Pests and diseases play a major role in determining the success or failure of a turfgrass stand and are a huge problem for golf course superintendents who are attempting to maintain top notch playing conditions. [28] Conventional solutions to pests and diseases are easy to come by, and they are often sold as household goods. They range in levels of toxicity from chemicals with very little impact and low potential for harm, to chemicals that have been restricted due to the various threats they pose to human and environmental health, or chemicals that have active ingredients in them that are restricted, but the product is still available. [29] Alternatives to pesticides are becoming more popular, and there are an increasing number of resources available to superintendents who are looking to reduce their pesticides use. For examples, check out: Beyond Pesticides and Green Links.

There are also a series of management practices that can be incorporated along with natural products to reduce overal pesticides use. RI superintendents reported forty different pests and diseases that were present on their courses and almost forty different pesticides are used to combat these ailments. In addition to chemical solutions, the majority of superintendents have a wide array of practices that serve as alternatives to pesticides such as Integrated Pest Management (IPM), cultural practices, and strategies that fall under no specific label. The majority of RI superintendents (79%) spray on a "preventative program," and the superintendents who do not, spray on a curative basis or if there are complaints from members or golfers. There are a total of ten different methods superintendents use as a substitute for, and way to reduce pesticide use. The graph below provides a visual display of the freqeuncy of use for the different practices, and descriptions of each practice follow.

* IPM as defined by course superintendent.

Spot Treatment
Spot treatment refers to the practice of applying pesticides directly to the area where diseases or pests are located. When a pest or disease arises, the area is located and treated (as opposed to spraying the entire course) Spot treatment is often used in conjunction with a preventative spray program, which makes it less of an alternative practice and more of an additional practice. Similar to hand watering, a water conservation practice, spot treating localizes the problem areas, and has the potential to reduce overall pesticide use if it is used as a replacement to preventative spray programs.

Monitor Pests
The practice of monitoring pests is both an IPM and a cultural technique. It involves establishing damage thresholds, as well as observing and documenting pest activity. Through continuous, careful observations superintendents begin to know target areas on the course that are subject to damage, and can prepare strategies ahead of time, before the diseases or pests becomes a problem. Determining when a pest is going to cause damage can be a huge benefit and save hundreds of dollars on pesticides.

Monitor Water Use
When water is monitored effectively over-watering is prevented, an unfavorable environment is created for fungi, and pesticide demands are lessened. Monitoring water use involves careful selection of irrigation timing and application. Current irrigation technology allows for on-site programming of sprinkler heads, and allows superintendents to format water output based on the specific needs of the golf course. Monitoring water can be greatly improved with the current irrigation systems that calculate water use, and can be programmed to fit the precise water needs of each course.

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Integrated Pest Management
IPM is a sustainable approach to managing pests by combining biological, cultural, physical, and chemical tools in a way that minimizes economic, health, and environmental impacts.[30] IPM is commonly thought of when alternatives to chemicals are on the table. However, IPM does not simply mean "organic" or "without chemicals." IPM incorporates a combination of practices that often involve chemical application, but at a "sensible" rate. IMP can be defined as "a system that relies on a combination of common-sense practices of preventing and controlling pests in which monitoring is utilized to identify pests, damage thresholds are considered, all possible management options are evaluated, and selected controls are implemented." [40]

Soil Maintenance Healthy soil can be maintained in a number of different ways, and is key to reducing pests and diseases. Practices such as verticutting, topdressing, aeration, and allowing for proper sun and water, and checking soil temperature and pH are all fundamental elements of maintaining healthy soil.
	Disease infestation on the green.

Organic Fertilizer
Natural organic fertilizers, such as fish emulsion and sewage sludge have low percentages of nitrogen and other nutrients, slow release rates, and low burn potentials. They tend to be expensive per pound of nutrients, but can be applied at high rates to give release of nutrients over most of the season.[32] Organic fertilizers do not remain in the soil as long as conventional fertilizers, thus higher or more frequent application rates are required. The benefits of organic fertilizers involve increasing organic soil matter, which increases the ability of the soil to supply nutrients to the grass. [33] Thus strong, healthy soils produce resilient and durable grass. Applying organic fertilizers was extremely useful according to the one superintendent who upheld the practice. He said they were more expensive, but very effective.

Dragging
Dragging is a cultural practice that is based off the principle idea of reducing prolonged leaf wetness in order to reduce disease presence. Dragging literally involves dragging a rope or hose across the turf in the early mornings it order to remove the dew. The success of this practice is undetermined by this study, but it was mentioned on two separate occasions by RI superintendents, and is a proven technique to reduce disease infestation. [31]

Resilient Grass Species
Planting a strong, durable and resilient grass species is a strategy one superintendent mentioned. The idea behind it is that if the grass is durable and can take care of itself, fewer pesticides are be required.

Biological Controls
Biological controls involve using pests and predators to wipe out or reduce the unwanted pests and predators. For examples, click here.

Preventative Spray Program
A preventative spray program involves spraying the greens, tees, and fairways on a regular basis. The majority of preventative programs spray every 3 weeks; however, some superintendents spray every two weeks, or even every seven days. The idea behind the preventative program is that if pesticides are applied ahead of time, pests such worms and beetles and diseases such as gray leaf spot and anthracnose can be managed before they become a problem.

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G.C. # 19 spent the least amount of money on pesticides. The superintendent primarily attributes his success to fertilizers. The superintendent primarily uses bentgrass on the greens, tees, and fairways, and has a special variety of bentgrass on the greens that he calls "performance EL-93."

G.C. #10 uses velvet bentgrass, which has been shown to be tremendously successful in minimizing water use as well as pesticide requirements. The superintendent of this course said he leaves things alone much more than other courses, and allows the grass to take care of itself. He also mentioned that he rarely sprays because of the costs associated with pesticides, and he said that diseases tend to go away on their own within a few weeks.

G.C. # 12 monitors his water use, and spot treats for pests and diseases. The superintendent said that although he spot treats, he thought it was better to use a preventative program. He also said that water has a big impact on fungi, and he makes an effort to control the amount of water he applies to his course. Monitoring water appears to work because G.C. # 12 spent only $400 on pesticides, where the average was $1,000 per acre per year.

G.C. #18 credits their success to well-maintained soil. The superintendent at this course stressed the importance of verticutting and topdressing the soil.

G.C. # 16 places a great deal of importance on spot treating, despite the seven-week preventative spray program the superintendent has in place. The superintendent said he scouts and monitors pests on the course, and sets thresholds which allow him to determine when it is appropriate to spray. He said he only sprays when he knows the pests or diseases are going to cause damage to the course.

G.C. # 13 has the most alternatives to pesticide practices, yet out of all the courses considered to be "successful," this course spends the most on pesticides, and applies the most water. The superintendent at this course referred to his combination of practices as "IMP." One of his strategies is to abbreviate prolonged leaf wetness by "dragging," a cultural practice that entails dragging a rope or a hose across the grass in the early mornings in order to remove dew, and discourage fungi. The superintendent recently started to apply organic fertilizers, and he commented on their expense, but also said they seem to work. He referenced the Department of Environmental Management (DEM) for his exposure to organic fertilizers and for the seminars they host on environmental maintenance practices for golf courses. He said he also scouts for diseases in order to have an idea of what is coming ahead of time. Other practices include not mowing in the mornings, verticutting, and the reduction of turf traffic.

The primary difference between the golf courses that spend the most money on pesticides and the courses that spend the least derives not from overall maintenance practices, species of grass, height of cut, or course status. The difference is due to what the members and golfers expect and demand, and what they are willing to tolerate. One of the superintendents who spent the least amount of money on pesticides said the members at his course accept some brown spots on the course. Where as the superintendent who spends the most on pesticides, uses some excellent alternative practices, however he commented that everything at his course was member driven. "Members who demand a fast course keep conditions on the edge of life and death." Recommendations regarding pesticide use can be found here.