Target Grade Level / Age Range:

Middle School

Estimated Time:

90 minutes

Virtual Learning

Use this document to convert the lesson into a virtual learning module for your students. Use the steps outlined to create the different elements of a Google Classroom or other online learning platform. You can also send the steps directly to students in a PDF, present them in a virtual meeting, or plug them into any other virtual learning module system.


Identify careers in the agricultural industry that help farmers manage pests – specifically soybean aphids – and how to address them.


  • Printed copies of page 28 of Soybean Aphid Field Guide – one per student
  • Printed copy of Soybean leaves aphid count document
  • Tape
  • Career cards (printed front to back)

Essential Files (maps, charts, pictures, or documents)

Vocabulary (with definitions)

  • Soybean – also called soja bean or soya bean, annual legume of the pea family (Fabaceae) and its edible seed. The soybean is economically the most important bean in the world, providing vegetable protein for millions of people and ingredients for hundreds of chemical products
  • Aphid – small sap-sucking insects and members of the superfamily
  • Economic threshold – In integrated pest management, the economic threshold is the density of a pest at which a control treatment will provide an economic return. An economic threshold is the insect's population level or extent of crop damage at which the value of the crop destroyed exceeds the cost of controlling the pest. Economic thresholds can be expressed in a variety of ways including the number of insects per plant or per square meter, the amount of leaf surface damage, etc.
  • Yield – the amount of a given agricultural product produced
  • Bushel – a measure of capacity equal to 64 US pints (equivalent to 35.2 liters), used for dry goods. A bushel of soybeans weighs 60 pounds
  • Hectare - a metric unit of square measure, equal to 2.471 acres or 10,000 square meters.

Background – Agricultural Connections (what would a teacher need to know to be able to teach this content)

The soybean aphid, Aphis glycines Matsumura, is the only aphid known to extensively colonize soybean fields in North America. This pest is a potential threat to virtually all soybeans grown in the US and Canada. However, some states are more at risk of economic infestations than others. In addition to geographical considerations, soybean fields at highest risk include those planted late and those that experience hot, dry weather that stresses the crop. Because soybean aphid populations can increase rapidly, growers should scout regularly, monitor population levels and be prepared to treat if necessary. Soybean aphids have many natural insect enemies such as lady beetles and their larvae that can help keep moderate populations in check. Fungal diseases are also emerging as important factors in aphid population regulation.

Interest Approach – Engagement (what will you do to engage students at the beginning of the lesson)

Aphid count on soybeans is used to determine if/when to spray insecticides to control the aphids. Soybean aphids have been a problem since they were first introduced between 2000 and 2004. Play the video Soybean Aphids from AgPhD Present slides 2-6 in the PowerPoint – Managing the threat.


  1. Hand out the career cards to the class – preferably one per student. Have each student read their card silently to themselves. Organize students into a large circle in the classroom. Go around the circle and have each student explain their career to the class. Encourage questions and discuss each career. Students can go in order. But preferably they listen for their career in the previous explanation and that will indicate the order in which the careers are discussed.
    1. Farmer – I own 330 acres of land and raise corn and soybeans. I rotate my crops every year planting half in corn and half in soybeans. They next year I rotate the acres. I sell my grain to local elevators and the corn and soybeans get turned into many different food and industrial products. In 2006 I started to see a decreased yield in my soybean fields because of insects. I asked a crop scout to come and help me identify the problem.
    2. Crop Scout – I send most of the summer months outside working on my tan (farmer’s tan that is). I drive around the countryside and then walk corn and soybean fields to help farmers identify problems. Sometimes I use drones to monitor big fields. Other times I just walk them. I swing nets to capture flying insects. I inspect individual plants to find other insect, fungus, or other disease damage. I then work with an agronomist to help recommend a course of treatment to keep the plants healthy.
    3. Agronomist – I help identify the best course of treatment to keep plants healthy and growing well. If the field is affected by a fungus I might recommend a fungicide. If the field is affected by weeds I might recommend a herbicide. But if the field is affected by insects I will recommend an insecticide to treat them. I work with an entomologist specializing in invasive species to identify what insect is affecting the crop.
    4. Invasiv e species entomologist – I work with insects that have been introduced to the United States from other countries. The soybean aphid was introduced from China. I study how the insects have spread and try to figure out management strategies. Sometimes management strategies include integrated pest management and so I work with my other entomologist colleagues.
    5. Integrate d pest management entomologist – I help identify natural predators to invasive species. Integrate pest management means that we use many different approaches to combat pests like insects. We try strategies like prevention, crop rotation, and tillage. Some pests like aphids have natural predators (ladybugs) that will help control them. But sometimes the ladybugs can’t keep up and so we have to spray insecticides. I work with a chemical applicator to determine the best insecticide.
    6. Chemica l applicator – I help farmers spray their fields with fertilizer, herbicides, and insecticides when needed. I am always safe around chemicals and wear proper protective clothing. I want the chemical to be applied directly to the plant so that it doesn’t drift away and cause problems in other fields. I use special nozzles that have been developed by an engineer to help direct the flow of the chemical spray.
    7. Engineer – I design spray nozzles and other component parts that might be fitted onto a tractor or implement used in farming. I’ve been working on a sprayer lately that will change the size of the water droplets, the width of the spray, the direction of the spray, and the rate of the spray. All of these modifications will help apply just the right amount of chemical to a field when needed. But the chemical mix is all controlled by a computer, so I need to work with a computer programmer.
    8. Compute r programmer – I write code for computers in modern tractors and implements. My programs tell the machines how much water to mix with each chemical and will regulate the mixes. I can also program the computer and tractor to only spray the chemical on the field where it is needed. This prevents using too much chemical and wasting money spraying where it isn’t needed. To stay safe, I use proper mixing rates that are set by regulators.
    9. Regulator – I work for the Environmental Protection Agency and help determine the safe levels of pesticide application. I look at all of the scientific research and help decide the correct dosage that can be applied to fields. I work closely with chemists at crop science companies to set these regulations.
    10. Chemist – I work for a crop chemical company and study the chemistry of insecticides. There are a lot of ingredients in every single pesticide we put out on market. I want to ensure they are effective at killing insects, but safe for plants, animals, and humans. Once we determine the correct dosage we make sure it is clearly labeled on the container and work with a graphic artist.
    11. Graphi c artist – I design the labels that might be on a container of insecticide. It is important to communicate the brand, so I might design a specific logo for each insecticide. But it is also important to make sure people are aware of proper usage procedures and any potential risks. I include all of those in the label design. Farmers need to learn about how to properly use the chemicals and so sometimes I’ll work with a videographer to help communicate those messages.
    12. Videographer – I create TV advertisements, how-to videos, and other video segments to help explain the insecticides to farmers and consumers. I help explain why it is important to manage soybean aphids and how the insecticide will help do that. Sometimes I interview botanists to get a better understanding of how it all works.
    13. Botanist – I study plants and how they grow. This includes understanding how fertilizers make them healthier and how insects and diseases might weaken them causing lower yield. For example, aphids will not only pierce the soybean plant and suck out fluids that it needs, but by doing so they create a wound in the soybean plant can be susceptible to diseases getting into the plant. I work with plant breeders to help make plants like soybeans hardier.
    14. Plan t breeder – Some plants are naturally resistant or more tolerant to diseases and insects. But those plants don’t always produce the best fruit or seeds. I work to find naturally resistant variety of plants and cross them with plants that have a high yield to create hybrid vigor. But sometimes natural crosses don’t always work. I work with geneticists to determine if any of these traits are ideal for biotechnology research.
    15. Geneticist – I look at the genetic makeup of plants to try and make them better. I’m looking at genes that may make soybeans resistant to aphids. The gene might make the plant smell bad to the aphid. Or it may produce a toxin that would kill the aphid if the aphid tried to eat the soybean plant. But my research is only just beginning. It will be at least 5-7 years before we see results. Then it might another 10-15 years before the crop is ready for farmers. We want to make sure it is safe and there aren’t any unintended consequences. I work with college professors and other researchers to conduct these field safety trials.
    16. College professor – Part of my job involves research and I am currently testing different varieties of soybeans to see how they grow in this climate. Once we identify a variety that is ideal for this climate and soil type I will share my findings with seed processors.
    17. See d processor – I contract with farmers to grow seeds that other farmers will then plant for their crops. I make sure the seed is sorted, cleaned, treated, weighed, and is high quality for planting. I ensure that it is certified weed free and ready for next year’s growing season. I work with the local cooperative manager and seed salesman to ensure they have what they need.
    18. Cooperative manager / seed salesman – I help get farmers the type of seed they need to plant each year. I help them decide what seeds are best for their soil, their climate, and their farm. To by seeds, fertilizer, and chemicals, sometimes farmers need loans. I can also connect them with bank lenders to secure loans.
    19. Agricultura l Lender – I work at a local bank but I specialize in helping farmers get the capital (money) they need for their operation. I might grant them a loan to buy inputs (like seed, fertilizer, or chemicals) or even things like machinery or more land. I work with them to ensure they pay back their loan over time. I work with the farmer and their accountant to help ensure that the business is stable and will continue to grow.
    20. Accountant – I am the accountant and bookkeeper, but I’m also a family member! Farms are often incorporated which is a type business structure to help manage risk. But our incorporated business is still just run by family members. I ensure the books are accurate and up-to-date. When I’m not managing the financial side of the business, I’m in the field helping the farmer with planting, harvest, and other chores.
  2. Diagnosing the problem, identifying the threshold
    1. Explain to students that all of the different careers will be working together as a team to try and identify whether or not the field should be treated.
    2. Play the following scouting video to help students understand the procedure of crop scouting and counting aphids: OR use slides 7-8 of the Managing the threat PowerPoint.
    3. Prior to class, past the printed soybean leaves (from soybean leaves aphid count.pptx) around the classroom. Pass out copies of the soybean aphid field guide to each student. Explain to students that each leaf that is placed around the room represents a random sample of a much larger field. Each leaf is 30 rows or paces from the next plant.
  3. Have students follow the instructions on the Speed Scouting for Soybean Aphids worksheet to collect their data. Directions for Speed Scouting:
    1. Go to a plant at random and start counting aphids. If less than 40 aphids are on the ENTIRE plant, mark a minus [-] for that non-infested plant. If you reach 40 aphids, STOP COUNTING (this is the speedy part!) and mark a plus [+] for that infested plant.
    2. Walk 30 rows or paces at random to find the next plant. Repeat Step #1 until 11 plants are sampled in different areas of the field. Total the number of infested plants [+] to make a treatment decision.
    3. If you must ‘CONTINUE SAMPLING’ (7-10 plants with a [+]), sample 5 more plants and use the new total number of plants to make a decision.
    4. If no decision is reached, sample additional sets of 5 plants until 31 plants are sampled. Remember, always use the total number of infested plants [+] to make a decision. If no decision can be made after sampling 31 plants, resample the same field in 3-4 days.
    5. A ‘TREAT’ decision must be confirmed a second time 3-4 days later. If confirmed, apply an insecticide in 3-4 days.
  4. After all students have gathered their individual data, bring the class back together and have them discuss whether or not they should treat the field or not. NOTE: Based on data collected, some students may decide that the field should not be treated. But, most students will likely discover that the field should be treated based on their counts. Lead a discussion on how students arrived at different answers. Facilitate a discussion until the group can reach a consensus.

Did You Know? (Ag facts)

  • As many as 31 states have seen soybean aphids in fields. Eight states around the Great Lakes and upper Midwest are at highest risk for infestation. These include Illinois, Indiana, Iowa, Michigan, New York, Ohio, Pennsylvania, and Wisconsin.
  • S oybean aphids are wingless in their colony-building phase. They later form wings and can migrate.
  • Common soybean aphid natural enemies include: a) multicolor Asian lady beetle, b) green lacewing, c) insidious flower bug, d) spined soldier bug, e) parasitoid wasp. 

Extension Activities (how students can carry this beyond the classroom)

  • Have students pick one of the careers that they discussed during the lesson. Have them conduct research about the career to learn more. If possible, have them interview a person who currently has that job.  

Suggested Companion Resources (books and websites)


Management Recommendations for Soybean Aphid (Hemiptera: Aphididae) in the United States

Author(s) (your name)

  • Will Fett

Organization Affiliation (your organization)

Iowa Agriculture Literacy Foundation

Agriculture Literacy Outcomes

  • T3.6-8.f. Identify the careers in food production, processing, and nutrition that are essential for a healthy food supply.
  • T4.6-8.f. Explain the harmful and beneficial impacts of various organisms related to agricultural production and processing (e.g., harmful bacteria/beneficial bacteria, harmful/beneficial insects) and the technology developed to influence these organisms.
  • T4.6-8.g. Identify science careers related to both producers and consumers of agricultural products
  • T4.6-8.i. Provide examples of science and technology used in agricultural systems (e.g., GPS, artificial insemination, biotechnology, soil testing, ethanol production, etc.); explain how they meet our basic needs; and detail their social, economic, and environmental impacts
  • T5.6-8.b. Distinguish between careers in production (farmers and ranchers) with those that directly involve consumers (business and nutrition)

Iowa Core Standards

  • MS-ESS3-3. Apply scientific principles to design a method for monitoring and minimizing a human impact on the environment.*
  • MS-ETS1-1. Define the criteria and constraints of a design problem with sufficient precision to ensure a successful solution, taking into account relevant scientific principles and potential impacts on people and the natural environment that may limit possible solutions.
  • 21.6-8.ES.1. Communicate and work productively with others, considering different perspectives, and cultural views to increase the quality of work.
  • 21.6-8.ES.2. Adapt and adjust to various roles and responsibilities in an environment of change.
  • 21.6-8.ES.3. Demonstrate leadership, integrity, ethical behavior, and social responsibility in all environments.

Creative Commons License

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