By Joe Magazzi & Christine Menapace
From the April 2024 Issue
Like it or not, pesticide bans and restrictions are increasingly being implemented across the country. As a result, many lawn and landscape professionals worry about being left without effective tools in their toolbelt to combat pests and disease. Finding viable alternatives to these compounds will be a major challenge for our Industry. However, this article provides some advice when it comes to alternatives.
Since I wrote my last article for Turf three years ago, there have been even more advances in technologies for safer synthetic or organic pesticides — especially for grub control. The timing for these advances couldn’t be better as solutions are needed to fill these large gaps in treatment options for a rapidly growing pest problem.
(Photo: Adobe Stock / JJ Gouin)
Neonicotinoids Bans Are Expanding
In the past few years, there has been a flood of legislation passed or introduced in multiple states (federal legislation has not yet been passed, although bills have been introduced) restricting the use of neonicotinoids (neonics). Neonic pesticides include: acetamiprid, clothianidin, dinotefuran, flonicamid, imidacloprid, nitenpyram, nithiazine, thiacloprid, and thiamethoxam. Environmental groups champion these laws and point to studies showing neonicotinoids are toxic to bees, pollinators, and beneficial insects required for food production. However, many in the U.S. Green Industry defend responsible, licensed use of neonics as an EPA-approved means of protecting plants and public health. Although there are other chemical compounds and ecological factors that contribute to pollinator decline; the neonicotinoids have been the focus of much of the legislation.
In New Jersey, for instance, a bill banning neonics for outdoor applications and applications to turf and ornamentals was passed in January 2022 and took effect this past October 31, 2023. According to the New Jersey Green Industry Council (NJGIC), which fought the legislation, many popular products will no longer be available such as Merit (Envu), Arena (Valent), and Meridian (Syngenta) along with many generic options containing the same active ingredients. Tree and ornamental control products like Zylam (Valent), are also off the market.
In New Jersey, Bartlett Tree Experts in Denville is one of the companies facing Spring 2024 without neonics. “Over the course of the last twenty plus years our customers have become accustomed to the high levels of insect control we’ve been able to provide through the use of imidacloprid. One of the unknowns is how that customer base will respond to lesser results,” comments Wayne Dubin, VP/Division Manager, who opposed the New Jersey law.
Similar neonic bans affecting outdoor (nonagricultural) use by lawn and landscape companies have been enacted in Nevada and Maine. While it’s difficult to stay up-to-date on all current legislation, other states with some degree of neonic restrictions either in effect or being considered reportedly include: Arizona, California, Colorado, Connecticut, Delaware, Hawaii, Illinois, Maryland, Massachusetts, Minnesota, Missouri, Nebraska, Rhode Island, Tennessee, Vermont, and West Virginia. In many states reclassifying neonics to “restricted use,” they are still able to be utilized by licensed professionals.
Synthetic Alternatives
Currently, the leading synthetic alternative to neonicotinoids for grub control is chlorantraniliprole, with Acelepryn® being the most widely used brand for professionals. The NJGIC also recommends Tetrino®, with a similar chemistry in tetraniliprole. Many applicators already using chlorantraniliprole-containing products as their standard grub treatment regardless of bans. Chlorantraniliprole is an insecticide in the chemical class of anthranilic diamides which has a very unique mode of action. It targets an insect’s ryanodine receptors, disrupting muscle function and leading to paralysis and eventual death. Since this receptor is specific to mostly pest-type insects (e.g., white grubs), chlorantraniliprole has very limited off-target toxicity—including most pollinators.
Chlorantraniliprole does have some drawbacks; the major one being that it is only effective for preventative use with grubs. Chlorantraniliprole can’t be used much past hatch, if even that, when turf damage becomes evident to homeowners, and they reach out in desperation for treatment. There are also water proximity restrictions, in some areas, due to toxicity to aquatic invertebrates.
Curative application alternatives mentioned by the NJGIC include organophosphates such as trichlorfon (Dylox®) and carbamates such as carbaryl (Sevin®). These compounds have high off-target effects on beneficial insects and should be used with caution.
Defining Organic
Of course, in states banning neonics, organic alternatives will become more sought after. Yet regardless of legislation, organic lawn care is expected to show a growth rate of 13.7% from 2021 to 2028, according to gitnux.org, outpacing the anticipated growth grate of general lawn care.
Yet what exactly defines a product as organic? There is widespread confusion surrounding the definition of “organic” and what constitutes an organic product. The word “organic” was a very unfortunate choice: the technical definition of organic is any molecule that has carbon in it. Therefore, even glyphosate and the aforementioned neonicotinoids, which contain carbon in their structures, can technically be termed organic by the chemical definition.
Legal organic standards exist solely for food products and food production. With no legal standards regarding organic turf care, how do you judge? You’ve no doubt run across “OMRI listed” products, but what does it mean? The Organic Material Review Institute (OMRI) is a nonprofit organization that provides third-party verification for manufacturers of products used in agriculture as well as turf care. Products that meet these standards are considered OMRI Listed® and can be used for certified organic production and processing.
More turf applicators are utilizing these types of natural or OMRI-Listed products for their turf, tree, and plant health care programs. Other agencies that approve as an input for organic production include the Washington State Department of Agriculture (WSDA) and California Department of Food and Agriculture (CDFA).
Organic Solutions
BTG/grubGONE. One organic product establishing itself to be as good as that of the best-practice synthetic alternatives, including the neonicotinoids, is grubGONE!®. This bio-insecticide utilizes natural Bacillus thuringiensis galleriae (Btg, or BTG) to combat white turf grubs as well as adult beetles, rendering it effective for both curative and preventative applications. This efficacy is supported by university studies including those done by entomologists at Rutgers University, Ohio State University, University of Nebraska, and NC State University.
BTG spares bees and pollinator and does not have any off-target toxicities on beneficial nematodes and parasitic wasps which also kill grubs. This preserves nature’s own grub control system, establishing a one-two punch for maintained control. grubGONE! is OMRI-listed, exhibits at least a three-year shelf life, and remains effective even in cooler temperatures.
Beneficial nematodes. Another organic product used for grub control is the beneficial nematode Heterorhabditis bacteriophora (Hb). While Hb nematodes have demonstrated effectiveness in controlled studies, their efficacy can be limited in real field conditions primarily due to their need for constant soil moisture — a challenge during hot summer months when grubs are most active. Nematodes also have short lifespans outside their natural environment, requiring cold, dark conditions, necessitating refrigeration. Application timeframe is within a week or two, ideally conducted out of direct sunlight or even in the dark. Consequently, the effectiveness of nematodes in real field conditions may be inconsistent or unreliable.
Beyond Grubs: Cultural Practices
Back in New Jersey, where the neonic ban is now in effect, Dubin from Bartlett Tree Experts is less concerned about lawn grubs and more concerned about destructive shrub and tree pests. Given the neonic ban, “Certain wood boring insects, certain leafminers, and a handful of others will be very challenging to control,” he says.
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The strategy for 2024, he says, is one Bartlett already practices: a focus on overall tree health. “Our approach to plant health care is holistic. Good cultural practices, proper watering, removal of dead/diseased tissue, and mulching are just a few methods we employ to maintain healthy plant activity. We release beneficial or predatory mites and insects if it’s a good option and the pest population justifies it.”
He continues, “Certain OMRI certified products are extremely effective tools in the toolbox. An effective plant health care program incorporates many different techniques. A horticultural oil application in the late Winter/early Spring can reduce pest populations, but only if eggs are overwintering on the plant… My point is inspection, timing, and thresholds are all factors in decision making as to what, if any treatment to make. Organics are one tool in the toolbox. They work in some instances, but not in others… We are taking the approach that we will continue to work on improving overall plant health and vigor and we’ll see how it goes.”
Magazzi, MS, is the President and Co-founder of Green Earth Ag & Turf®, a company that provides eco-friendly products and consulting services to land care professionals. He has been involved in the research and development of microbial-based products for use in turf care for many years. Magazzi has a Master’s in genetics (with a microbiology focus) from the University of Connecticut-Storrs.
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