Assess the pests

Supplement - Pest Control // IPM

Know when it’s time to tweak your IPM program, and make sure your team is kept in the loop.

April 5, 2018

Train your staff to scout thoroughly and communicate what they see effectively.
Courtesy of Steven Rettke, Rutgers

program should improve the bottom-line of a company.

“Consider this: pesticides are pretty darn expensive. The ultimate goal of a successful IPM is to reduce the amount of pesticides used in the operation,” says Juang-Horng Chong, associate professor/extension specialist for turf and ornamentals and entomology at Clemson University.

He says a successful IPM program will lead to reduction in pesticide use, thus reduce materials and labor costs associated with pesticide application, and thus the company’s bottom-line.

“The benefits of IPM also have a social component, i.e. protect worker safety and protect the environment,” he adds.

When should growers tweak or scrap an IPM and devise a new approach to safeguard their stock against pests?

Natural predators are part of a complete IPM program.
Photo courtesy of Cornell

“Sometimes we have no choice but to tweak the IPM plan when an unidentified problem never seen before arises with plants in the nursery or landscape that can only be attributed to the environment — soil characteristics, slope, location — in which they are growing. This would include application of water and fertilizers. In this case, an effort to alter the environment to promote good growing conditions and all aspects of managing the crop(s) or landscape should be considered until a new production IPM plan evolves,” says Winston Dunwell, an extension specialist for nursery crops at the University of Kentucky Research and Education Center.

An IPM program “should be a living thing,” meaning that it should be flexible enough to respond and adapt to changes at any point in time, Chong says.

When reviewing an IPM program, growers should ask key questions, according to Sarah White, an associate professor and nursery specialist in the Department of Plant and Environmental Sciences at Clemson University.

  • Do you need more pesticide applications than you have in the past?
  • Are you seeing outbreaks of pests you haven’t noticed?
  • Are weeds becoming a greater issue, even though you’ve been managing them as you did in the past?
  • Might it be time to take a step back and look at your operation as a whole? Did you switch chemicals?
  • Did you switch substrate suppliers?
  • Are your liners from a different supplier?

If the answer is yes to one or more of these questions, she says growers should re-evaluate their systems as a whole and determine where opportunities for excluding pests present themselves.

“Prevention is easier than the cure,” she says.

Trapping and monitoring is an important part of an IPM program. 
Photo by Kelli Rodda

A closer look

Nursery IPM methods require site-specific information, says Steven Rettke, Rutgers Nursery/Greenhouse IPM coordinator.

“Every nursery typically contains at least several key pests, key plants and key locations that will be unique to each site. These concepts are extremely useful in order to simplify monitoring procedures at any given site. They will enable field technicians to concentrate on plants and locations that are prone to problems, as well as those plants and locations that have low aesthetic thresholds,” Rettke says.

The potential control strategies for problems at each site need to be considered. Will cultural or biological methods solve the problem or are pesticides necessary? Rettke says solving problems with cultural or biological solutions should always be the first line of defense with all IPM programs. When they become necessary, a list of preferred pesticides should be listed for each specific problem.

David Shetlar, professor emeritus with the Department of Entomology at Ohio State University, believes that an IPM should be under a constant state of improvement.

“If a pest is getting out of hand, one should ask, ‘why?’ What needs to change to better manage this pest? It isn’t always making another spray, but changing insecticides, modifying the environment (improving spacing, pruning, etc. to make the plants less susceptible to a pest), or even deciding to grow a different plant or cultivar that is less susceptible to pests,” Shetlar says.

After the growing season has ended, owners and managers should review logs and determine if there were some hot issues that could be better managed in the future. Seek help from other experts and find out if they have some additional pest management ideas, he adds.

Chong says nursery managers should “know thyself.”

“Understand what you are growing, growing conditions, your (and your client’s) tolerance and requirements, what may be bugging your plants, and what can be done to control these pests,” Chong says. “Select the pest management tools that can help achieve enhanced tolerance and requirements under your growing conditions and put these tools in a logical sequence and context.

“Understand that it is likely an IPM program has to be developed for each pest and crop combinations, and that the programs would have to be flexible enough to adjust to the pest and growing conditions on the ground and new tools that become available.”

IPM programs must be flexible, and spray programs should be monitored.
Photo by Kelli Rodda

Complete buy-in

Communication from top to bottom among staff is crucial to a workable and effective IPM.

“One thing many owners and managers did not do when introducing a new program or a change in program is to communicate with the folks on the growing floor,” Chong says.

Frequently, managers will find a new means of pest management with a safer material or through production practice alteration that must be conveyed to the staff, Dunwell says. Involving staff in educational opportunities and in evaluating the existing plan leads to success.

“Field workers see problems that arise and often have an opinion about the best way to avoid it happening again,” Dunwell adds.

While a manager and a staff member may disagree on what is best, by working together to try different approaches to small batches of plants, there should be buy-in when a method shows promise for inclusion in an IPM plan.

Keep good records about which pests were found, as well as when and where. Yan Chen, LSU

“Telling people the `why’ is often the most important thing you can do to get your staff on board with changes in practice,” White says. “Tell them your vision of what success looks like, what happens if you make this change. Then offer them the tools to successfully implement change-whether that at your state grower meetings and workshops-or at larger venues like Cultivate. Give them the informational/knowledge tools needed so they know they can help make the change and cooperate in the success this change will make at your operation.”

Luis Cañas, an associate professor of insect ecology in controlled environments in the Department of Entomology at Ohio State University, says a new IPM is “simply a culture shift.” If owners, managers and staff all are in support of IPM, it will work.

“The biggest hurdle is empowering employees to make decisions and not be afraid to try new ways of managing pests. Reward successes and don’t be overly critical of new things that didn’t work,” Cañas says.

Tetrastichus planipennisi, a natural predator of emerald ash borer.
David Cappaert,

Don’t be afraid to talk to other nursery producers and to university extension specialists. If a new procedure is on the table, don’t be afraid to try it, even in a limited scope.

Cañas says IPMs can be adopted at any time. In some cases, it is simply best to merely keep good records of where pests are located, what was done about them, and what worked and what didn’t work.

“With these records, you will have a better idea of what approaches should be used the next season. Once a program is up and running, it becomes easier to tweak it every year,” Cañas says.

John Torsiello is a Torrington, Conn.-based writer.