Unit 1: Are Two Crops Better Than One?
Lesson 1: Monocroppingvs Diversifying Planting Techniques
Grade Level: Third Grade
Time Required: 45 minutes
Primary AZ State Standards:
(Cross-reference “Standards Matrix” for full listing)
Science:
S03-S3C2-01: Describe the beneficial and harmful impacts of natural events
and human activities on the environment (e.g. forest fires, flooding, pesticides).
S03-S4C3-01: Identify the living and nonliving components of an ecosystem.
Objective(s):
Students willidentify the living and nonliving components of an ecosystem.
Students will make and test predictions of which model of farming (monocropping or diversified planting) would be better for farmers and/or the environment.
Background Information:
In third grade science standards (Strand 3: Science in Personal and Social Perspective), students are encouraged to describe and think about their place in the world as consumers, decision makers, problems solvers, and planners in relation to the impact of science and technology on human activity and the environment. The question of whether or not monocropping is a sustainable system of farming, financially or environmentally, will fuel the activities for this unit of gardening curriculum in the third grade.
Monocropping is an agricultural method of farming where fields are planted with one type of crop, such as corn or alfalfa. In monocrop farms, fields are often replanted year after year with the same crop. When crops are not rotated, soils become depleted of certain nutrients which the same crops continue to use repeatedly. As a result, farmers have to add large quantities of fertilizers to replenish lost nutrients. Similarly, the soils often become contaminated by fungi and pests which will continue to negatively impact the same types of crops planted; consequently, farmers are forced to apply pesticides and fungicides to neutralize the soil. Entire fields of crops can be wiped out by a strain of fungus or bugs if they are not destroyed which means serious trouble for the farmer.
Diversified planting, on the other hand, is a different method of farming where fields or sections of fields are planted with a variety of crops. This method of farming mimics a more natural balance of biodiversity in an ecosystem. Farmers will rotate crops in different fields to help soils recover naturally since some crops are heavy feeders (use a lot of nitrogen from the soil), and some actually add nitrogen back to the soil. By diversifying plantings, farmers can reduce the need or avoid having to use artificial fertilizers, pesticides, and fungicides by not depending so heavily on one type of crop. Additionally, if a pest decides to attack a particular type of crop, the farmer’s fields will not be entirely destroyed.
So why do farmers choose to monocrop? Farmers often feel like they can get a corner on the market by specializing in a crop. A farmer can invest in just the right equipment for the job by large amounts of seed, and effectively work their way into a niche by producing a lot of one type of crop. Although diversified plantings may be viewed as a less efficient way of farming in the short run, this exercise will show that it can actually save farmers a lot of financial heartache.
Pre-lesson Preparation:
- Gather materials listed in the beginning.
Activity Instructions:
Ecosystems: Living and Nonliving Component Discussion
Whole group, small groups
10 minutes
- Ask students to explain, “Who has heard the expression, ‘Two heads are better than one?’” Explain we are going to do a group brainstorm to start our lesson, because we can get more ideas if we work together.
- Ask students to explain the word ‘ecosystem’. Ecosystem means a place where things live together. Living and nonliving components work together.
- As follow up to ecosystem definition discussion, ask student to explain the difference between living and nonliving components. Living things grow, require food, water, air, reproduce, etc. Non-living things do not “grow”, require nourishment, need shelter, etc.
- Put student in small groups. Hand out pictures in Appendix 3A: Pictures of Ecosystems. In groups, have students look at the pictures and list living and non-living components they see (or don’t see!) in the ecosystem.Living (biotic) = bugs, plants, animals, birds, bacteria, fungus. Non-living (abiotic) = sunlight, water, soil, rocks, nutrients.
- Share ideas with whole group.
- Ask students to explain how both non-living and living components work together. E.g. Non-living components such as water and sunlight are essential for plants to live.
- Reiterate, “So ecosystems are systems that are in balance with living and nonliving components, of things living together.”
- Tell students, “Today, we are going to look at some of the ways that people affect ecosystems through choices that we make about farming and gardening.”
Monocropping and Diversified Planting Discussion
Whole group
10 minutes
- Tell students, “Today is your lucky day. This class is receiving a gift of land from my very old Aunt Gertrude who decided she was getting too lonely living all the way out the woods of Vermont all by herself. Would you like to see a picture of your land?”Show students Appendix 3B – Picture of Student Vermont Land.
- Tell students, “But the catch is, all of you have to use the land for farming, or else you’ll have to pay all this extra money to the government to own your land. So, today, we are going to look at some choices you have. Take a good look at this picture before we move on. Think about what the land looked like before you decided to start farming on it. What does this ecosystem look like now?”
- Show students Appendix 3C – Monocropping and Diversified Planting pictures. Explain that monocropping means planting one type of plant every year, and diversified planting practices involve planting many different types of plants in different places in a rotation as described in the Background section.
- Ask students,
Which do you think look more natural, or more similar to the land right after Aunt Gertrude gave it to you?
Which do you think is better for the ecosystem? Why?
Which do you think is better for farmers? Why?
- Discuss advantages and disadvantages with the class as mentioned in the Background section or as students bring up ideas. Ask students to think about living and nonliving component of the ecosystem.
- Tell students, “We’re going to test some of your ideas now by playing a farming game.”
Monocrop and Diversified Planting Simulation Game
2teams
25 minutes
- Divide students into two teams. Explain the game.
One team decides to monocrop half of Aunt Gertrude’s land. The other team decides to have diversified planting.
2-3 people on each team will be farmers and the rest will be crops (make sure there is an even number of crops).
A variety of events will happen that will affect your farm ecosystem and possibly your wallet! You want your crops to survive so you can sell them at the end of the season and get more money.
Each team starts with $100. Each crop (person), at the end of the season, can be sold for $100… if it survives!
- Tell the monocrop team that they are growing corn. Give the diversified planting people choices of crops to plant. Choices include:
- Corn
- Peppers
- Squash
- Peas
- Lettuce
- Tomatoes
- Give each team $100 of play money in $10 increments. Have students designate roles (2-3 farmers, the rest crops).
- Start running through scenarios. Students follow instructions on cards.
- After going through all the cards, when someone goes bankrupt, or when all the crops die, analyze the financial consequences the two systems of farming by having students count their money. Monocropping is financially riskier in the end.
- Ask students to think about which system seemed harder on the environment, then share with students the information from the Background section. Make sure to emphasize the environmental hazards of monocropping, and the advantages of diversified plantings.
- Ask students, “So at the beginning of this lesson, we said two heads are better than one. What would you think about the statement, ‘Two crops are better than one?’”