IR-4: A Pest Management Resource For Growers

IR-4: A Pest Management Resource For Growers


The USDA APHIS Inspection Station at the Miami Airport was part of a tour that took place prior to the 2013 Biennial IR-4 Ornamental Horticulture Workshop.

Almost 40 years ago, IR-4 (Interregional Research Project Number 4) began serving the ornamental horticulture industry, helping to facilitate the registration of pest management tools. IR-4 does this primarily by surveying growers about their pest management issues and then hosting workshops to review survey results and set priorities for the coming years.


Most recently, IR-4 coordinated a meeting of researchers and industry members on pollinator health and neonicotinoid chemistries to start a discussion on the needed research. The next step will be to get the outcomes from that workshop out to the public.

“While making science-based decisions is very important, how we communicate scientific results is equally important,” says Cristi Palmer, the ornamental horticulture program manager of IR-4.

With the outcomes from that workshop, IR-4 can aid in the development of data that is needed in the ornamental horticulture industry.

A Resource For Specialty Crop Growers

Formed in the 1960s, IR-4 was initially created to serve the edible crops industry, because at the time, growers of specialty crops such as lettuce and small fruits didn’t have much to apply to crops to manage pests, diseases and weeds. In the early 1970s, the ornamental horticulture industry found itself facing the same issue. There weren’t enough tools to manage thrips, botrytis or various weeds, Palmer says.

The IR-4 ornamental horticulture program was started in 1977 with a focus on non-edibles, both in greenhouses and in nurseries. The organization aids the registration of sustainable pest management technology for specialty crops by developing data to support new EPA tolerances and labeled product uses. IR-4 works with researchers nationwide to conduct efficacy research on tools, as well as crop safety research.

“Without those data, many chemicals would be registered only for major food crops, which means that important and effective new chemistries would be unavailable to greenhouse and nursery growers,” says Lin Schmale of the Society of American Florists (SAF).

Growers Help Guide Research

Every other year, IR-4 conducts its Grower Extension Survey as a way to get a pulse on the industry and determine what problems are not being addressed by the current tools, Palmer says.

“Sometimes the responses that we get back are on the most recent issue the growers faced. This survey helps guide our research,” Palmer says.

The results are shared at a biennial workshop, which is attended by a mix of researchers, growers, trade representatives, like Schmale, regional field coordinators and representatives from the crop protection industry.

The group looks at the survey results, as well as which projects have carried over from previous years and which tools might be available to screen.

“There are not always new tools available to expand our knowledge base on any given project,” Palmer says. “For example, with bacteria, IR-4’s done a lot of research, and we came to the conclusion a couple of years ago that the best products were the current standards, the copper-based materials.”

Once research is gathered, IR-4 compiles all project information together on its website. Each pest or disease will have a project summary that encompasses all of the research that’s been done on that particular pest, Palmer says.

“We then take that information and provide it to the crop protection industry so they can update their labels, or write new labels,” she says.

IR-4 will work with any crop protection company that has tools that need to be registered, from larger companies like BASF, Bayer and Syngenta, to the smaller companies who may only have one tool to develop.

Project summaries are posted on IR-4’s website and available to the public.

Four Decades Of Success

IR-4 efforts have led to 35,000 ornamental horticulture crop uses since the ornamental horticulture program was started. In addition, there have been more than 23,000 studies conducted, more than 100 registered products and nearly 32,000 completed trials. And just in the last 10 years, the program has contributed data to the registration of 72 different products.

“IR-4 is a very strong, and all-too-often unsung supporter of the green industry and our growers,” Schmale says. “IR-4 research has supported the availability of over half of the crop protection tools (traditional chemicals, biopesticides and other reduced risk materials) that are now labeled for nursery and greenhouse use.”

One of many examples of how IR-4’s ornamental horticulture program has helped the industry is the creation of a whitefly management plan.

After the introduction of the Q-biotype whitefly in 2004, IR-4 began helping to screen new materials.

“Even though the B-biotype had been present in the U.S. for many years, the cotton and vegetable industries were alarmed that the newly found Q-biotype could cause them great economic damage,” Schmale says.

SAF helped lead the formation of a taskforce, including representatives of the floral and nursery, cotton and vegetable industries, scientists and regulatory officials, Schmale says.

“(Palmer) was one of the key scientists involved, and was instrumental in helping to put together the whitefly management program,” she says.

IR-4 helped identify some new materials that were fairly promising, including Judo and Safari, and developed an overall whitefly management plan that growers would be able to use.

Palmer says the plan was to help growers manage whiteflies from the cutting stage, all the way to the finish, with an eye toward resistance management, as well as just being able to manage pests.

“The whitefly management program continues to guide growers in recommended chemical rotation strategies to avoid development of whitefly resistance to chemicals important to ornamental horticulture, and also important to the cotton and vegetable industries,” Schmale says. Visit to see the plan.

A New Focus On Pollinators

December’s workshop on pollinators was an entirely new type of event — not one of IR-4’s standard priority-setting workshops.

“This workshop was focused on the impact of the systemic products for pollinators as it relates to ornamental horticulture production,” Palmer says.

Like the standard workshops, there were individuals from various areas of the industry present, as well as an entomologist focused on understanding pollinators and scientists involved in analytical chemistry and understanding how to do residue analysis of products.

“Our mission is to help grow sets of tools, and if the tools need to be assessed in a different way, IR-4 can help guide people in how to assess those tools by having meetings like this workshop,” Palmer says.

She adds the workshop helped to develop a much better understanding of the risk assessment process and the types of data that are needed to go into developing risk assessment for the ornamental horticulture industry.

“One of the interesting things is that honey bees are the model pollinator for the EPA. Even though the ornamental horticulture community doesn’t use honey bees for their pollinator services, that’s the model pollinator all of the risk assessments need to be based upon,” Palmer says. “Bumble bees would be much more useful, because they’re the pollinators that might come into contact with any residues potentially coming from our crops. But, all of our studies need to be done in the context of honey bees.”

Another outcome of the workshop was the understanding that, while IR-4 can assist with the hazard side of the risk assessment equation, the exposure side is going to be trickier, because out of the thousands of crops produced by the industry, not all of them are attractive to pollinators, Palmer says.

“We need to have a better idea of the percentage of crops we produce that are attractive to pollinators, and therefore would present a risk to the bumble bees or to the pollinators in general,” she says. “That’s a number that needs to go into the equation. Right now, we don’t know what that number is.”