Growers manage pests to produce great apples

By Marcia Anderson

Working in the Office of Pesticide Programs, I was excited to learn of the progress New England fruit growers were making in using “integrated pest management” to reduce pests and pesticides in their orchards.Apples

As we go about picking and eating our apples, many of us are not aware how much New England apple growers must battle pest problems on a continual basis. Pests like moths, mites, and fungi see an apple orchard as a place to eat or reproduce. In general, they have found that integrated pest management – an environmentally friendly, common sense way of controlling pests that involves a variety of approaches – is the way to go. Because the ecology in every orchard is different, pest conditions and circumstances are different for every grower and thus solutions may vary.

Integrated Pest Management has become increasingly engrained in apple pest management in this area over the past 30 years. Most New England growers live right on their farms and have found the most effective way to control pests is by using scientifically-based IPM practices that help their orchards in the long-term.

Growers monitor their orchards weekly from early spring through the growing season to determine pest pressures. Growers and crop consultants become intimate with their location, learn about past disease and pest pressures and about the ecology of their orchards. And they learn something new every year.

Farmers who use integrated pest management can reduce their two highest bills: for pesticides and fertilizers and for fuel.

Maintenance and sanitation are key parts of preventing pests in apple orchards.

Apple scab damage on mature fruit.

Apple scab damage on mature fruit.

Farmers have learned it helps to keep the land and water as clean as possible. In the fall, growers clean the orchard floor, cutting suckers off tree trunks, and clearing weeds from under the trees. Fallen leaves, grass clippings, and winter prunings are mulched and returned to the soil. Leaves chopped small will decompose more quickly and neither the pests nor diseases will have anywhere to overwinter, reducing the pest populations in the orchard the next spring. The only thing removed are the apples.

Simply maintaining this level of sanitation successfully reduces the presence of apple scab, one of the most persistent pest problems in orchards. Apple scab comes from a fungal spore that overwinters on the ground. It normally requires a fungicide, or anti-fungal pesticide, to stop its development. Those spores make leathery-brown scabs that blemish the fruit and reduce its perceived quality and this its economic value.

Apple scab also damages trees by creating lesions on leaves that spread and interfere with photosynthesis. A bad scab infection can shut down a whole tree and spread quickly throughout the orchard.

Other pest prevention methods include planting pest-resistant varieties and replenishing nutrients. Apple trees need specific nutrients to produce quality fruit. When hundreds of bushels of apples per acre are removed annually, nutrients are removed from the soil. Soil should be monitored and nutrients added when necessary.

So why should we care about pest prevention and the appropriate use of pesticides on our apples? One reason is that apples are prevalent in the diets of our children. And they’re good for us! Using the scientifically-based best practices of integrated  pest management, northeastern apple growers can give us high quality apples at reasonable prices.

More information from EPA on Integrated Pest Management: https://www.epa.gov/managing-pests-schools/introduction-integrated-pest-management

You can see New England growers discuss using IPM to prevent pests in series of three videos by the New England Apple Association.

Editor's Note: The views expressed here are intended to explain EPA policy. They do not change anyone's rights or obligations. You may share this post. However, please do not change the title or the content, or remove EPA’s identity as the author. If you do make substantive changes, please do not attribute the edited title or content to EPA or the author.

EPA's official web site is www.epa.gov. Some links on this page may redirect users from the EPA website to specific content on a non-EPA, third-party site. In doing so, EPA is directing you only to the specific content referenced at the time of publication, not to any other content that may appear on the same webpage or elsewhere on the third-party site, or be added at a later date.

EPA is providing this link for informational purposes only. EPA cannot attest to the accuracy of non-EPA information provided by any third-party sites or any other linked site. EPA does not endorse any non-government websites, companies, internet applications or any policies or information expressed therein.

Fruit Orchard Growers Find that Disrupting Apple Pest Mating Leads to Better Fruit

Apple blossoms

Apple blossoms

By Marcia Anderson

Taking a drive in the country, I pass numerous apple orchards, the trees in full bloom, with petals falling across my windshield, like giant snowflakes when a cool spring wind blows. I am reminded of a time, a generation ago, when people were spraying pesticides by the calendar in orchards and on farms throughout the country. For instance, they would spray for a certain pest before the trees’ buds broke in the spring, then every 7–10 days thereafter. The spraying occurred whether the pests were there or not because people were not scouting their crops to assess pest levels. Growers finally realized that pests don’t carry calendars and that their emergence varies from year to year. This validated the need for pest monitoring.

Today’s growers monitor certain pests with the aid of traps designed to include a chemical to attract only one certain pest. Such traps utilize chemical lures. The lures are synthetic copies of the chemicals (pheromones) the females emit to attract the males for mating. In apple orchards, traps, such as the one pictured here, are hung in the trees. The bottom of the trap is coated with an adhesive to capture the male insects. It is very effective control tactic for San Jose scale, codling moth, and oblique banded leafroller in lieu of pesticide applications.

With regular trap monitoring, growers know exactly how many moths are out in the orchard, which is the pest pressure, which in turn, helps them to determine if and when further treatment is necessary. When a moth is caught, growers know that first generation (the overwintering generation) has flown. Then, they can calculate degree days for the first generation eggs to hatch. At that point growers make a decisions for action. Northeast apple orchard growers discuss implementing pest-specific pheromone control strategies in their second video.

2.Apple maggot damage to an apple (Photo: E.H. Glass, New York State Agricultural Experiment Station, Bugwood.org)

Apple maggot damage to an apple
(Photo: E.H. Glass, New York State Agricultural Experiment Station, Bugwood.org)

An effective use of pheromones is in conjunction with a small dose of pesticides. This is an extremely effective and low cost cultural control to disrupt insect mating of apple maggots. The apple maggot is a small fly that lays its eggs in a fruit. The maggots hatch and eat the fruit. Sometimes you do not see them until you bite into the fruit finding half a worm. UGH. Pheromone traps can trap apple maggot flies. A red plastic ball with an apple odor in the center resembles an apple hung on a tree and will visually and chemically attract the apple maggot fly. Orchard growers also use an organic insecticide on top of the fake apple. When an apple maggot lands on it, it licks the insecticide, which will cause the females to cease laying eggs and they will eventually die. In this way, the rate of insecticide needed is drastically reduced. A grower’s last resort is the application of chemicals.

Pheromone trap (Bugwood.org)

Pheromone trap (Bugwood.org)

Apple growers have now found the most effective way to control their pests is by using scientifically-based practices like Integrated Pest Management, or IPM, that have positive long-term effects on their orchard. IPM is an effective and environmentally sensitive approach to pest management that relies on a combination of common sense practices. IPM programs in apple orchards use current comprehensive information on the life cycles of pests and their interaction with the environment. This information, in combination with available pest control methods is used to manage pest damage by the most economical means, and with the least possible hazard to people, property and the environment. IPM takes advantage of all pest management options including inspection and monitoring for apple pests, the sanitation and maintenance of the orchard and trees, cultural practices like traps, and the judicious use of less risky pesticides, such as pheromone traps, first. IPM dictates that sprays are used only when needed for effective and long term control.

With IPM, you have to get to a certain pest population level, or threshold, before treatment is recommended. So, determining how to deal with pests based on thresholds is a primary step. How many of a certain kind of pest do you have? The threshold depends on the specific insect, weed, or disease.

There are a few challenges to IPM, not only in apple orchards, but with regard to controlling any pests. It is very important to rotate the modes of action of the chemicals that are used. Because with any pest population, if you use the same mode of action repeatedly, there are always a few pests that survive, creating future generations of pests who have developed pesticide resistance. The end result of resistance is that the overused pesticides lose their efficacy for pest control.

For more on apple IPM read: Apples for the Big Apple…Managing Pests to Produce Quality Apples. So the next time you eat an apple, think about your local apple growers and how they are using IPM to provide you with quality produce at reasonable prices.

 

 

About the Author: Marcia is with EPA’s Center of Expertise for School IPM in Dallas, Texas. She holds a PhD in Environmental Management from Montclair State University along with degrees in Biology, Environmental Design, Landscape Architecture, and Instruction and Curriculum. Marcia was formerly with the EPA Region 2 Pesticides Program and has been a professor of Earth and Environmental Studies, Geology, and Oceanography at several universities.

Editor's Note: The views expressed here are intended to explain EPA policy. They do not change anyone's rights or obligations. You may share this post. However, please do not change the title or the content, or remove EPA’s identity as the author. If you do make substantive changes, please do not attribute the edited title or content to EPA or the author.

EPA's official web site is www.epa.gov. Some links on this page may redirect users from the EPA website to specific content on a non-EPA, third-party site. In doing so, EPA is directing you only to the specific content referenced at the time of publication, not to any other content that may appear on the same webpage or elsewhere on the third-party site, or be added at a later date.

EPA is providing this link for informational purposes only. EPA cannot attest to the accuracy of non-EPA information provided by any third-party sites or any other linked site. EPA does not endorse any non-government websites, companies, internet applications or any policies or information expressed therein.

Apples for the Big Apple:  Northeast Growers Manage Pests to Produce Quality Apples

By Marcia Anderson

Apples are susceptible to fungal spores that can blemish the fruit and cause economic harm to the growers.

Apples are susceptible to fungal spores that can blemish the fruit and cause economic harm to the growers.

Apple growers battle pest problems on a continual basis. To pests, such as moths, mites, and fungi, an apple orchard is a place to eat or a place to reproduce. Because the ecology in every orchard is different, pest conditions and circumstances are different for every grower, so controlling pests using Integrated Pest Management (IPM) makes sense.

IPM has become more and more engrained in apple pest management in the northeast over the past 30 years because most northeastern growers live right on their farms. It is in their best interests to keep the land and water as clean as possible. Apple growers have found the most effective way to control their pests is by using scientifically-based IPM practices that have positive long-term effects on their orchards.

Growers monitor their orchards weekly from the beginning of spring through the entire growing season to determine pest pressures. The growers and crop consultants become intimate with their location, learn about past disease and pest pressures, and learn the ecology of their orchards. Admittedly, they learn something new every year.

There is also an economic impact when farmers use IPM. They stand to reduce their two highest bills – chemicals (pesticides and fertilizers) and fuel – when they follow the five components of IPM. These components are: 1) prevent pests; 2) identify the specific pests present; 3) set economic thresholds for each pest as a decision making tool; 4) monitor for pests and their damage, and; 5) use a combination of management tools.

Maintenance and sanitation are key parts of preventing pests in apple orchards. Every year, growers follow a rigorous routine in the fall by cleaning the orchard floor, cutting suckers off tree trunks and clearing weeds from under the trees. Fallen leaves, grass clippings, and winter prunings are mulched and returned to the soil. By chopping the leaves into small bits, they will decompose more quickly and neither the pests nor diseases will have anywhere to live over winter. This reduces the pest populations that will be in the orchard in the next spring. The only thing that is removed are the apples.

Just by being particular about maintaining this degree of sanitation, growers have been very successful in reducing the presence of apple scab, one of the most persistent pest problems in orchards. Apple scab comes from a fungal spore that overwinters on the ground. It normally requires a fungicide (anti-fungal pesticide) to be sprayed in order to arrest its development. Those spores go on the fruit and make leathery-brown scabs that blemish the fruit. Blemished fruit is considered to be of lower quality, so its value is reduced leading to an economic loss to the grower.

Apple scab also damages the tree because it creates lesions on the leaves that spread and interfere with photosynthesis. A bad scab infection can shut down a whole tree and spread quickly throughout the orchard. So orchard sanitation is a very important part of scab control.

Other pest prevention methods include planting pest-resistant varieties and nutrient replenishing. Just like people, apple trees need specific nutrients to keep them healthy to produce quality fruit. When hundreds of bushels of apples per acre are removed annually, it means a lot of nutrients are removed from the orchard soil. Monitoring soil nutrient levels and adding nutrients, as needed to maintain tree health, is an essential component of IPM.

Apple trees need a wide range of macro nutrients (those needed in large quantity to provide energy) including nitrogen, phosphorous and potassium. Nutrients are added either directly to the soil or by spraying on the tree leaves. Many soils in the northeast have high phosphorous levels and adequate nitrogen levels. If nitrogen is needed, it is most often applied through foliar application. Potassium is the macro nutrient (those vitamins and minerals needed in small amounts for proper plant health) that needs to be replaced on a regular basis. By running soil tests and recording the number of bushels of apples that were removed, growers can calculate how much potassium must be added back to the soil. Micronutrients, such as calcium, magnesium, zinc, boron and manganese, also need to be replenished. These are all added through foliar applications.

You can see northeastern growers discuss using IPM to prevent pests in a series of three videos by the New England Apple Association.

So why should we care about pest prevention and the appropriate use of pesticides on our apples? One reason is that apples are very prevalent in the diets of our children. They’re used to make juice and sauce, as well as eaten raw. They’re good for us! Utilizing the scientifically-based best practices of IPM, northeastern apple growers are able to provide us with high quality apples at reasonable prices.

 About the Author: About the Author: Marcia is with EPA’s Center of Expertise for School IPM in Dallas, Texas. She holds a PhD in Environmental Management from Montclair State University along with degrees in Biology, Environmental Design, Landscape Architecture, and Instruction and Curriculum. Marcia was formerly with the EPA Region 2 Pesticides Program and has been a professor of Earth and Environmental Studies, Geology, and Oceanography at several universities.

Editor's Note: The views expressed here are intended to explain EPA policy. They do not change anyone's rights or obligations. You may share this post. However, please do not change the title or the content, or remove EPA’s identity as the author. If you do make substantive changes, please do not attribute the edited title or content to EPA or the author.

EPA's official web site is www.epa.gov. Some links on this page may redirect users from the EPA website to specific content on a non-EPA, third-party site. In doing so, EPA is directing you only to the specific content referenced at the time of publication, not to any other content that may appear on the same webpage or elsewhere on the third-party site, or be added at a later date.

EPA is providing this link for informational purposes only. EPA cannot attest to the accuracy of non-EPA information provided by any third-party sites or any other linked site. EPA does not endorse any non-government websites, companies, internet applications or any policies or information expressed therein.