Unit Title: Animals and Pollinators

Season: Spring

Possible sources of Integration: science, social studies

Key Words: Pesticide residue, integrated pest management, cover cropping, crop rotation, companion planting, pollinators

Link to Content Standards:

SCHS-S3C1-01: Evaluate how the processes of natural ecosystems affect, and are affected by, humans.

SCHS-S3C1-03: Assess how human activities can affect the potential for hazards.

SCHS-S3C3-02: Describe biotic (living) and abiotic (nonliving) factors that affect human populations.

Brief Summary of Unit (including curriculum and unit goals):

Animals and pollinators help the garden grow. It is important to be able to identify these other life forms that influence the success of the garden, and work to create habitat to invite these beneficiaries into the garden. This unit provides the students with a brief introduction to the various animals and insects who inhabit the garden. Students will understand the dangerous affects of pesticide use and learn the alternative strategies of integrated pest management. They will also learn the importance of pollinators and make a list of plants to attract more pollinators to the garden.

What enduring understandings are desired?

Students will understand:

Pesticide use not only affects the environment (land, soil and water), but it also affects our own bodies and other animals and insects consuming sprayed produce.
There are many different alternatives to using pesticides, termed integrated pest management.
Pollinators are critical to food production and need to be protected from various threats.

What essential questions will guide this unit and focus teaching and learning?

What is pesticide residue?
What is IPM?
Who are our plants pollinators?
Why are pollinators important?
What can we do to increase pollinator populations?

What key knowledge and skills will students acquire as a result of this unit?

Students will know:

Key terms: Pesticide residue, integrated pest management, cover cropping, crop rotation, companion planting, pollinators
Alternatives to pesticide use including the cultural, mechanical, and biological pest management strategies.
What plants attract which pollinators and why pollinators are important to the garden.

Students will be able to:

Research native plants and make recommendations for the garden.
Exercise greater consumer knowledge in the grocery store in the interest of their personal health.
Implement IPM strategies in their garden.

What evidence will show that students understand?

Performance Tasks (summarized)

IPM Scenario cards: Students will test their knowledge of integrated pest management and make recommendations for different scenarios.
Pollinators and Plants: Students will research native plants and make a plant list to attract pollinators to the garden.

Quizzes, Tests, Prompts, and Work Samples (summarized)

Unprompted Evidence (e.g., observations and dialogues)

Teacher observations of students during work on the performance tasks.
Participation in class discussions and reflection questions.

Supermarket Sweep

Objective:

To learn about the amount of pesticides on our foods

Standards:

SCHS-S3C1-01
SCHS-S3C1-03

Materials:

Supermarket Sweep food cards
What’s in Your Food? worksheet

Directions:

Divide the class into two teams. Each team is going to have to go shopping for a meal that they are preparing for the class. The goal is to purchase items that they think will be the healthiest meal that they could serve.
They will need to choose enough food to serve everyone. So if they want to make a pizza, they will need to choose more than one tomato card.
When they have finished shopping let each group explain their meal and why they think it is healthy.
Hand out the Pesticide Residue worksheet and have each team tally their purchases. They should record the number of items they bought in the quantity column, and multiply that by the numbers listed in the residue column. They should then add the total.
The team with the lower number wins the supermarket sweep for preparing the healthier meal. The total number represents the amount of pesticide residues (measured in parts per million) that each student ate during the meal.
What is a pesticide? What is a pesticide residue? Much of the food we buy at the supermarket has been treated with various chemicals. These chemicals leave a residue on the food that in turn we eat. Some crops have more residue than others. Hand out the What’s in Your Food? worksheet.

Discussion:

The residue levels on the worksheet are representative of the tolerance levels for pesticide residues as determined by the EPA and USDA. When a pesticide is sprayed to control a pest or disease, it is estimated that only 5% of the chemical actually meets its target. The remaining 95% is left in the soil, runs off into the watershed, or is left on the skin of the fruit or vegetable. These residue levels do not guarantee that our food is safe because they do not take into account that people eat more than one item. So while 50 parts per million of residue might be a tolerated level, in fact most people eat more than one tomato. There is evidence that these chemicals are stored in the fat cell of our bodies, and have even been found in breast milk.
In addition to ourselves eating the food, what are other harms of these chemicals? Consider the workers spraying the chemicals, in addition to the soil, water, and non-targeted insects and other animals.
Discuss the alternatives to this approach. Remind students that they have a choice in the kind of foods they are buying. Organically certified foods are those grown without chemicals. Additionally, produce purchased locally, while it may not be organic, typically has less chemical residue. For one thing, local farmers do not have to coat their produce with fumigants, which is done with produce traveling a long way to market to preserve ripeness. Moreover, it is easier to discuss these issues with a local farmer and neighbor than a farmer on the other side of the country or world.

*This activity are adapted from The Pesticide Banquet, a lesson in Sara Coblyn’s French Fries and the Food System. Boston: The Food Project, 2000.

Pesticide Residue Worksheet

Food Item / Residue / Quantity / Total
Apple Juice / 75
Apple / 100
Bell pepper / 100
Broccoli / 25
Cabbage / 25
Carrots / 50
Cheese / 100
Corn / 25
Eggplant / 50
Garlic / 25
Green beans / 50
Grapes / 100
Jelly / 75
Lettuce / 100
Butter / 25
Mayonnaise / 25
Milk / 25
Onions / 0
Peanut Butter / 200
Peach / 100
Potatoes / 100
Spinach / 100
Strawberry / 100
Squash / 50
Tomatoes / 50
Tuna Fish / 25
Whole wheat bread / 50
TOTAL:

*Residue Levels are measured in parts per million and have be rounded and estimated.
What’s in Your Food?

% with Pesticides / % with 2+ Pesticides
Peaches / 97% / 87%
Apples / 92% / 79%
Sweet Bell Peppers / 82% / 62%
Celery / 94% / 80%
Nectarines / 97% / 85%
Strawberries / 92% / 69%
Cherries / 91% / 76%
Pears / 87% / 47%
Grapes (imported) / 85% / 53%
Spinach / 70% / 31%
Lettuce / 59% / 33%
Potatoes / 81% / 18%
Carrots / 82% / 48%
Green Beans / 65% / 39%
Hot peppers / 55% / 28%
Cucumbers / 73% / 32%
Raspberries / 48% / 23%
Plums / 56% / 10%
Grapes / 61% / 22%
Oranges / 83% / 29%
Grapefruit / 62% / 23%
Tangerines / 67% / 33%
Mushrooms / 60% / 22%
Cantaloupe / 55% / 20%
Honeydew melon / 59% / 14%
Tomatoes / 47% / 14%
Sweet potatoes / 58% / 10%
Watermelon / 29% / 14%
Winter squash / 40% / 13%
Cauliflower / 72% / 8%
Blueberries / 28% / 10%
Papaya / 24% / 5%
Broccoli / 28% / 3%
Cabbage / 18% / 5%
Bananas / 42% / 2%
Kiwi / 15% / 3%
Sweet peas (frozen) / 23% / 2%
Asparagus / 7% / 21%
Mango / 7% / 1%
Pineapples / 8% / 1%
Sweet corn (frozen) / 4% / 0%
Avocado / 1% / 0%
Onions / 0% / 0%

Source: Environmental Working Group

Integrated Pest Management

Objectives:

To define integrated pest management
To learn tools of sustainable agriculture

Standards:

SCHS-S3C3-02

Materials:

Sustainable Agriculture Scenario Cards
Sustainable Agriculture Solution posters

Directions:

Engaging Question:

What are some of the problems that can occur as a result of chemical use in the garden or farm? Over only a few generations, pests can develop resistance to the chemicals and become super-pests or super-weeds. Chemicals can affect other insects and organisms that were not the intended target. For example, applying a chemical to a flowering fruit will affect the pollinators (birds, bees, butterflies, and the like) visiting that flower. These chemicals are petroleum-based, depleting a non-renewable resource. They also end up in our soils and waterways, in addition to the residue that ends up in our bodies. Moreover, this strategy is expensive.
Integrated pest management is one alternative to the use of chemicals. Has anyone heard of integrated pest management (IPM)?

Sustainable Agriculture Scenarios:

Divide class into small groups and give each group a gardening scenario card. As a group they need to come up with an integrated pest management plan to get rid of the pest without having to use chemicals. Though they do not yet know the IPM strategies, this will test their creativity.
Their plan is written on one of the solution posters that you should tape up to the blackboard. They need to decide which plan is best for their situation—there may be more than one that applies.
Give the groups a few minutes to discuss and then go around and present to the class. What until after the discussion to give the correct answers.

IMP Lecture:

Let’s break down the three words. What does integrated mean? Using many different methods together. What does pest mean? Bugs and life that cause harm to our plants. What does management mean? Controlling or handling a situation. All together this means using different methods together to control a pest problem. IPM is an ecological approach to reduce and eliminate the use of pesticides and chemicals in a garden.
Brainstorm examples of possible IPM strategies that the students might already now: cover cropping, crop rotation, physical barriers.
IPM is a customized pest management program. Instead of applying broad techniques to different problems, such as chemicals and fertilizers, IPM is specific to the problem and crop.
IPM strategies can be broken down into three categories: cultural, mechanical, and biological:

Cultural IPM Strategies:

Maintaining the health of the garden soil and plants to prevent insect problems to begin with is the first step of IPM. Plants that are under stress suffer more quickly and severely for pest infestations. How can we maintain the health of our garden?

Healthy soil and proper water drainage
Crop rotation—Moving crops around the garden each year will help to build the soil and “trick” the pests. Some crops add a certain nutrient to the soil and take another nutrient from the soil as they grow. By rotating the crops, the plants are helping on another by adding to the soil nutrients that another plant may need.

Planting appropriate varieties—crops that are adapted to a particular place will not need chemicals to support their growth.

Companion planting—this is the practice of intercropping plants that are beneficial to one another. One plant provides something the other plant needs and vice versa. For example, corn, beans, and squash are historical companions. Corn provides a natural pole for bean vines to climb. Bean vines also help stabilize the corn plants, making them less vulnerable to blowing over in the wind. Spiny squash plants also help discourage predators from approaching the corn and beans. Beans fix nitrogen on their roots, improving the overall fertility of the plot by providing nitrogen to the following years’ corn. The shallow-rooted squash vines become a living mulch, shading emerging weeds and preventing soil moisture from evaporating, thereby improving the overall crops’ chances of survival in dry years.

Keep things neat—pull weeds that are a potential source of food and habitat for pests. Clear the garden of piles of debris, which also serve as good cover and hiding places for pests.

Mechanical IPM Strategies:

Hand picking—simply spending time in the garden and hand picking any pests is one sure way to kill them. Collect these bugs in a jar and feed them to the garden chickens or neighboring birds.

Hose plants off with water—be careful, as this technique might burn some plants in the summer sun.

Spray plants with soapy water—this is particularly effective with aphids. Aphids breath through their skin. The soap reduces the surface tension of the water so that it will not bead, and effectively suffocates the aphid.

Sticky traps

Row covers—thin, polyester fabric is often used to cover plants. This allows for sun and water to pass through, but provides a barrier for insects.

Biological IPM Strategies:

Use other living creatures to control insects and pests. These creatures are either predators or parasites:

Predators—insects that eat other insects: lady bugs and green lacewings eat aphids; praying mantises eat insects in general; assassin bugs eat caterpillars
Parasites—insects that lay eggs on or within host insect and use that insect for food: parasitic wasp lays eggs in aphid eggs causing the aphids to form a stiff immobile form called a “mummy”. The Braconid wasp only lays its eggs on the hornworm. The eggs feed on the hornworm in order to hatch, and this eventually kills the pest.

IPM can also involve the use of pesticides, though this is carefully timed and controlled to maximize effectiveness and minimize risk. This does not apply for organic growing.

Discussion:

Revisit the scenario cards. Knowing what you know now, would you recommend any different strategies to the problems? What strategies can we employ in our garden?

Scenario Cards

Case #1

You are gardening at your home one day and discover that all the leaves on your tomato plants have been chewed. You search the plants for an insect and find dozens of green caterpillars called tomato horn worms on all your plants. What do you do to get rid of the pest?

Answer—hand pick, introduce beneficial wasp.

Case #2

Each year you plant potatoes in the same garden bed at your house. Each year hundreds of Colorado potato beetles attack your plants and eat the leaves, leaving you with a poor potato harvest. What can you do to get rid of the pest?

Answer—rotate the potatoes to another part of the garden next year.

Case #3

Grasshoppers are invading your garden!!! They are multiplying by the hundreds! You have tried hand-picking them, but they are too fast and hop away from you, plus there are just too many and you don’t have enough hours in the day to catch them all. What do you do to get rid of the pest?

Answer—row cover to act as a barrier between grasshopper and plant. Also introduce birds that like to eat grasshoppers into the garden.

Case #4

The corn in your garden is short and immature when your neighbor’s is ready to harvest. There is no evidence that a pest is eating the corn and it is getting enough sun and water. You determine that the problem is poor soil. What can you do to improve the soil, and as a result, improve the growth of your corn?

Answer—companion planting, plant beans to add nitrogen to the soil

Case #5

The weeds are taking over your garden beds. They are growing taller than your corn and you can keep up with weeding them all. What can you do to suppress the weed growth?

Answer—companion planting, plant squash and other like plants to suppress the weed growth, heavy mulching around plants.

COMPANION PLANTING

BENEFICAL INSECTS

PHYSICAL BARRIERS

CROP ROTATION

Animals in the Garden

Objective:

To know the animals that live in and around the garden
To understand the purpose of domesticated animals in the garden
To discuss some of the conflicts that arise between the urban and wilderness interface

Standards:

SCHS-S3C3-02

Materials:

Pollinator ID Cards
Stephen Buchmann and Gary Nabhan, “Holding the Globe in Our Hands,” in The Forgotten Pollinators (Washington, D.C.: Island Press, 1996), 131-143.
Pollinator and Plants Worksheet
Plant books

Directions:

Engaging the Question:

Brainstorm a list of wild animals that live in the area. Gophers, prairie dogs, elk, deer, foxes, snakes and birds
Discuss the relationship between the animals and the garden. What problems and benefits do these animals pose? Gophers burrow tunnels underground and damage plant roots. Snakes are natural predator to gophers. Prairie dogs also burrow tunnels, called towns, and like to munch on garden plants. They took are prey to snakes. Elk and deer also like to snack on garden foods. Foxes are generally more interested in garden animals (chickens, ducks) and tend to leave plants alone. Birds can eat fruit bearing bushes, but, like bats, birds will also eat insects.
Brainstorm a list of garden/farm animals. Chickens, turkeys, ducks, pigs, sheep, horses, cows, cats, dogs.
Discuss the ways these animals contribute to the garden’s ecosystem. What roles do they play in the garden? A chicken will eat garden insects and soil bugs and lay eggs or provide meat. As they scratch the ground for bugs, they effectively till the soil, laying valuable manure fertilizer in the soil along the way. All animal manure is of great value to the soil. Cats and dogs can serve as garden protectors, deterring and even catching gophers, mice, and other pests.

Pollinators: