A ban on some uses of neonicotinoid pesticides in New Jersey will go into effect in fall 2023. With existing restrictions in five other states and at least 11 more states considering limiting use of the pesticides, it is time to look at what else is available to take their place for those providing care for trees and ornamental shrubs.

A neonicotinoid is a type of systemic agricultural insecticide resembling nicotine. Some studies have found a link between neonicotinoids, or neonics, and declining bee populations. This is a chief reason for the bans. For more on the state bans, see the article “New Jersey Neonic Ban Coming in 2023” in the January 2023 issue of TCI Magazine.

We asked key people at the TCIA corporate member companies that manufacture pest-control products to explain a little bit about the neonics issue and what alternatives are available now or may be in the works.

Rob Gorden is director of urban forestry and business development for Arborjet Inc., a 21-year TCIA corporate member company based in Woburn, Massachusetts.

“Neonics have been in use here in the U.S. since the 1980s, and have proven invaluable in our fight against crop and ornamental pests as well as tree-killing invasive pests, such as Asian longhorned beetle (ALB), where it remains one of the very few solutions to protect hundreds of thousands of at-risk trees,” says Gorden.

“Well-meaning but often emotionally driven arguments have been made to restrict and, in some states ban, the use of neonics. Also, some state legislatures have successfully limited their use, at times without the prudent input of the scientific community.

“While there are other products that currently exist, including a number we have manufactured and continue to manufacture as alternatives, few offer the broad spectrum or longevity represented by imidacloprid (which is a neonicotinoid),” says Gorden. “Products such as Azadirachtin (AzaSol) are organic in nature, working against soft-bodied pests, but offer shorter duration and are seldom effective against tree killers. Others, such as Acephate (ACE-jet), offer quick knock down of a broad list of pests, but provide limited longevity of control for insects having multiple generations per year. Our longest-duration product, TREE-äge (Emamectin benzoate) – also applied and sealed safely within a tree – offers multiple years of control against many of the same insects controlled by neonics, and is even more broadly used in tree protection.

“We have found that one of our strong-est successes in states has been that our application technology is widely seen as an alternative to banning individual control products,” says Gorden. “The Arborjet tree-injection technology places a small dose of control product directly into the tree’s vascular system through a special plug that seals the chemistry inside the tree, limiting off-target exposure, photolysis or microorganism decomposition and preventing release into the environment.

“In fact, the active ingredient of such products as IMA-jet (imidacloprid), is effectively applied with less than a teaspoon needed for an entire tree, protecting it for a year. Our technology has been used by USDA APHIS (Animal and Plant Health Inspection Service) to protect about 500,000 trees against the Asian longhorned beetle. It is the technology that makes the difference, as nothing is sprayed into the air, taken up by off-target flowering plants or run off into groundwater. States such as California have put on hold plans to ban neonics due to their outsized protective value to their crops and their economy,” says Gorden.

“Regardless of which products one uses to protect trees, shrubs or crops, proper understanding of pest life cycle, environmental considerations, risks and methodology are just common sense. We must be stewards of the environment first, while protecting plants facing growing attacks by both native and exotic pests, and under stress from climate changes,” says Gorden. “Tree injection offers many positive alternatives to products applied by spray or soil-drench applications, and has a very favorable environmental posture, regardless of the control product selected.”

Chip Doolittle is president of ArborSystems Inc., a 27-year TCIA corporate member company based in Omaha, Nebraska.

“The problem with bans like these is they are broad strokes to take out things that are perceived to be a problem,” says Doolittle. “Someone sees on TV that imidacloprid may kill bees. Even though there is no credible evidence to show that, it’s in the news. They say, ‘OK, imidacloprid is a neonicotinoid. Let’s ban all neonics, regardless of whether all neonics are toxic to bees.’

“In our case, we have an alternative neonic registered. But it is still a neonic,” says Doolittle. “Not all neonics are as toxic to bees. I attended a plant-health-care seminar with Dr. Whitney Cranshaw as the speaker. He addressed these issues and further said there are neonics that are 400 to 600 times less toxic to bees. That is why we have another neonic registered. It does not have a lot of the bee language that is present in several of the other neonics, such as imidacloprid, dinotefuran, thiomethoxam and others.

“We in the ornamental world using neonics are a very, very small slice of the neonic pie,” says Doolittle. “Does this legislation take into consideration that neonics are used in the animal-health world, such as in Advantage for dogs to get rid of fleas and ticks? How about the agriculture world? How about industrial uses, such as wood coatings to stop termites?

“We do have an alternative, which is ArborSystems’ Boxer Insecticide-Miticide for tree care, which is used to control EAB and 30 other insect pests,” says Doolittle. “But imidacloprid controls many other pests not covered by this product. We will be looking further to find other alternatives.”

Patrick Anderson is an arborologist, or regional technical director, with Rainbow Ecoscience, a 25-year TCIA corporate member company based in Minnetonka, Minnesota.

“As you know, there are a lot of insecticides registered for use on ornamental trees and landscapes that would be effective on pests that neonicotinoid products would also be effective for,” says Anderson. “The key distinction for neonicotinoids is they can be applied systemically – soil applied or tree injection – making them reduced risk for other arthropods in the environment. With the definition of a neonicotinoid alternative being an insecticide that’s effective when applied systemically, our options become greatly reduced.

“Mectinite (emamectin benzoate 4%) is effective on a variety of leaf-chewing pests that have been managed by neonicotinoids in the past. Examples include Japanese beetle and sawfly. Mectinite also is effective on a range of lepidopteran leaf feeders, such as spongy moth and bagworm, in which neonicotinoids did not provide predictable control. The neonicotinoids were often used to manage several boring insects, like two-lined chestnut borer.

“Mectinite is highly effective against boring insects, including clearwing borers, that the neonicotinoids did not control well,” says Anderson. “Mectinite will predictably control leaf-feeding insects for one full season and boring insects for two seasons. While Mectinite would not be the first choice to manage many of our piercing and sucking insects, it does control lepidopteran, including leaf-feeding caterpillars and clearwing borers, pests that the neonicotinoids did a poor job of managing.

“Lepitect and Lepitect Infusible (acephate 97.4%) are applied as a soil injection or tree injection, respectively. Lepitect is unique in that it manages a broad range of piercing and sucking insects, for example aphids, scales, etc., and chewing insects, such as beetles, sawfly and caterpillars,” says Anderson. “Lepitect also controls spider mites, which the neonicotinoid imidacloprid may encourage in some situations.

“Lepitect moves into plant tissue quickly, seven to 14 days, but only has a 30- to 45-day residual,” Anderson explains. “Application timing is crucial when using Lepitect, and multiple applications per season may need to be applied for control of insects with multiple generations or extended feeding periods.

“There are some novel, reduced-risk products available that are not systemically applied but are considered reduced risk due to their mode of action. Proxite (Pyriproxifen 11.23%) is an insect growth regulator that works extremely well on scale insects and whiteflies. The active ingredient in Proxite acts as a juvenile hormone mimic,” Anderson says. “When young insects feed on Proxite-treated plants, they are unable to molt, which causes mortality. In addition, when female insects come into contact with Proxite-treated plants, they lay nonviable eggs, or the young born from those eggs are deformed. Finally, if Proxite comes in contact with eggs, the young born from those eggs are deformed.

“Acelepryn (Chlorantraniliprole 18.4%) has low impact on beneficial insects and nontargeted organisms and works extremely well against caterpillar pests. Additionally, studies have confirmed that Acelepryn may be nonhazardous to certain bee species.”

Test and verify

Steve Martinko is owner of Contender’s Tree & Lawn Specialists, a five-year TCIA member company based in Waterford, Michigan, and owner of Banner Sales and Consulting, Inc., a third-year TCIA corporate member company providing PHC products and based in Novi, Mich.

“Banner Sales and Consulting has been and is continuing to test and verify new products that are coming into the marketplace. We have numerous ongoing trials using various manufacturers that must be qualified as proven performers in order for us to vet these new alternatives,” says Martinko.

“Our trials in the lawn and landscape industry currently range across many markets, covering low- to high-
maintenance sites and rural and urban high-temperature micro-climates, while also including those companies that are modeled around more organically conscious approaches to PHC. The last thing we want to do is cause our clients increased treatment frequencies, risking greater phytotoxicity, because property owners are not happy with results and thus demanding additional treatments.

“As the EPA and Department of Agriculture agencies determine the environmental and economic impacts, the responsibility falls on all of us, as tree care professionals, to implement protocols and best-management practices that do not result in using new technologies that provide short-term results, causing businesses to respond with greater frequency,” says Martinko. “The risk to all beneficials could result in far-worse, unintended environmental problems despite the best lab testing and field testing by certain manufacturers.

“We embrace change with cautious attention to workflow details on a grand scale, and are confident there will be proven solutions that also balance economic pressures.”

Conclusion

Martinko and others quoted here would seem to support a point made in the January TCI Magazine article on neonic bans mentioned at the start of this article. In that piece, its author, Josh Leonard, stated, “Through selective use, appropriate application and proper application timing, the alleged negative impacts of these pesticides can be reduced while allowing crops, trees and other plants to prosper.”

TCI Magazine will keep its readers apprised of relevant state and federal updates regarding neonic pesticide regulation.