This hands-on lesson teaches students how precision agriculture uses geographic information systems (GIS) to help farmers and manufacturers make smart, efficient, and responsible decisions about how and when they plant, grow, irrigate, harvest, and transport crops. Grades 6-8

acre: a unit of area equal to 43,560 square feet (about the size of a football field)

bushel: a unit of measurement used in US agriculture that is equivalent to a volume of 64 pints, but is generally standardized by weight for different products; a bushel of wheat weighs 60 lbs, a bushel of corn weighs 56 lbs

finite resources: resources that do not renew themselves at a sufficient rate (nonrenewable)

Global Positioning System (GPS): a space-based satellite navigation system that provides location and time information in all weather conditions, anywhere on or near the Earth

irrigation: artificial application of water to the land or soil to assist plant growth

pivot: equipment used to irrigate fields (large sprinkler)

section: one square mile of land (640 acres)

variable rate irrigation: applies exactly the right amount of water to each foot/meter of the field

water use efficiency (WUE): the ratio of water used in plant metabolism to water lost by the plant through transpiration)

yield: measure of grains or seeds generated from a unit of land (agricultural output)

How many people will inhabit the world in 2050?  About 9.2 billion-- up from the 7 billion here today! And to make sure that everyone has enough to eat, global food production will need to increase by 70 percent.  So how exactly will this be done? Precision agriculture is the answer! 

Agriculture has changed dramatically throughout the past years.  In the past, almost everyone was a farmer.  These farmers produced a variety of crops and livestock that they fed to their immediate families.  Today, only 2% of the population is involved in production agriculture.  These farmers have specialized operations and feed 155 people (Prax, 2010).   

Key STEM IDEAS

Engineering allows us to define and solve real-world problems. Engineering concepts are changing agriculture by applying technology to improve food production. New equipment allows farmers to put in less labor to achieve larger yields. Precision agriculture is a farming management concept based on observing, measuring, and responding to inter- and intra-field variability in crops. Variable rate irrigation is a type of precision agriculture that involves applying water at a variable rate along the center pivot rather than one uniform rate along the entire length of the system. Variable rate irrigation has many uses for applying water at different rates to wet areas, different soil types, and overlapping pivots.   

Connections to Agriculture

Variable rate irrigation is made possible by the use of the GPS, field computer, rate controller, telematics, and a meter. GPS is used by farmers to create field maps to determine a field’s boundaries. Field computers allow farmers to control the application of fertilizers, herbicides, and pesticides through automated delivery systems. Farmers are able to monitor yields and moisture using computers. Rate controllers make it possible for farmers to control how much irrigation, fertilizer, etc. is applied in a field. Telematics allows information collected in a field to be transferred in the internet. 

Water use efficiency is calculated by determining the difference between irrigated yield and dryland yield and dividing that by the irrigation in inches. By performing these calculations, farmers will discover how much they should irrigate a section in order to increase yields and save water. 

1. Ask students if they know the current population of the world. (approximately 7 billion)
2. Ask, "Is our population increasing or decreasing?" (increasing) Inform students that it is estimated that we will have 9 billion people by the year 2050.  Farmers will need to grow as much food in the next 50 years as they did in the past 10,000 years combined.¹  
3. Ask students, "What necessities will we need more of in order to accommodate 2 billion additional people on the earth?" (food, water, energy, goods, and medical technologies, etc.)
4. Explain that we will need to find solutions to feed a growing population.  With limited resources (arable land, water, plant nutrients, etc.), we must do more with less without degrading our natural world.  Precision agriculture is the answer to increasing yields without increasing resources.  Inform students that they will be learning what precision agriculture is and how engineers develop these technologies.

Activity 1: Introduction

1. Following the Interest Approach students should begin to have an idea of the significance of the projected population growth in our world. Ask students to begin thinking about the overall impact of population growth as they watch the video, Agriculture is Under Pressure. 
2. Following the video, ask the class what the overall message is or what stuck out to them. Lead the discussion to conclude that farmers need to produce more food using the same resources.
3. Introduce the word efficiency. Discuss the definition and give real-life examples of efficiency that students will relate to. Point out that farmers will need to be more and more efficient to keep up with the demand for food. 
4. Ask students what type of resources farmers need in order to produce our food. As you discuss the following resources, point out that they are limited. We can't obtain more. Therefore, we need to be more efficient in our use of them.
   • Open space to grow crops or raise livestock
   • Water
   • Arable soil (soil containing adequate nutrients, a proper growing climate, and appropriate soil texture for plant growth)
5. Point out that farmers have become more efficient in previous years through the use of technology. Ask students, "What are some examples of technology that farmers are using today?" (Students may discuss GPS, maps, cell phones, automated irrigation systems, computers, large machinery (tractors) with automated features, etc.)
6. Introduce the concept of precision agriculture. Explain that precision agriculture implements various technological instruments to make agriculture more precise and efficient. As an example show the video clip Kinze Autonomy Project: Harvesting System. As the video clip plays ask students what they notice is different about the tractor (there isn't a driver.) Explain that this tractor is operated using robot and GPS technology. This allows a single worker to harvest an entire field. 
7. Introduce a second example of precision agriculture, variable rate application or (VRA). With VRA, different rates of an input such as water, seed, or fertilizer can be applied to a field to match the needs of each specific area. Show the video clip, Precision VRI: Make Every Drop Count to explain and illustrate the detailed technology that can be used to manage irration systems. 
8. Following the video, summarize why farmers would want to use variable rate irrigation.
   • Increase crop yields. Too much or too little water decreases plant health and crop yield.
   • Conserve water.
   • Provide exact and precise watering for each soil type and slope within a field. (Soil type can vary within a field. Clay soil holds high amounts of water which allows the roots to soak in the water for a longer time. In sandy soils, water can quickly run through the soil without penetrating the roots).
     • Use slide 2 of the Increasing Production with Precision Agriculture PowerPoint to give clarification on how soil type affects water holding capacity.
     • Use slide 3 to show a picture of a field being watered uniformly. Ask students if they can see a section of the field that needs more water.
9. Use slides 4-7 to summarize key points in preparation for the next activity.

Activity 2: Calculating WUE and Building a VRI System

1. Give each student one copy of the Increasing Production with Precision Agriculture student handout.
2. Complete "Part 1" of the handout. This section can be completed as a class, in groups, or individually. Slides 9-19 walk through the worksheet step-by-step.
3. Move on to "Part 2" of the handout. Guide students through the instructions for the variable rate irrigation activity in the student handout. Using slides 20-25, explain to students that they will build a device to vary water flow (just like in variable rate irrigation). Their goal is to build a system to divide 16oz of water into three cups with 2 oz., 6 oz., and 8 oz. of water in each.
4. Form students into groups of three. Distribute a 16 oz. water bottle, 3 cups, scissors, and a choice of straws or other materials to each group.
5. Using slide 25, discuss the engineering design process with students and have them complete page 4 of the handout.
6. Give students 10 minutes to construct a device to simultaneously divide the water into 3 different amounts. Allow students to test their design and share it with the class.
7. After their designs have been tested, instruct students to complete page 5 of their handout.

Encourage students to reflect on the activity using class discussion by asking the following reflection questions:

• Was your design successful?
• What could you do to improve your design?
• What career could you choose that uses these skills to develop instruments used in precision agriculture?
• Why is precision agriculture important?

Summarize the lesson with the following key points:

• Technology has developed and improved through time. It helps farmers/ranchers provide more food to more people.
• Using technology in agriculture decreases negative environmental impacts in our world.

1. http://www.un.org/en/development/desa/news/population/un-report-world-population-projected-to-reach-9-6-billion-by-2050.html
2. http://www.fao.org/news/story/en/item/35571/icode/
3. Producing Fruits: The Technology of Farming, 2013 

• Agricultural Drones
• Agricultural Engineering Video
• Crop Cards
• Crop Intensity Maps
• Dirt to Dinner
• Eat Happy Project video series
• Esri GIS for Agriculture
• Fighting Weeds: Can we reduce, or even eliminate herbicides by utilizing robotics and AI?
• Precision Agriculture Technologies and Factors Affecting Their Adoption
• SupraSensor Could be Super Tool for Precision Agriculture
• The Future of Farming & Agriculture video
• The Most Magnificent Thing
• What Happens When Farming Goes High-Tech?