When teaching about concrete items such as plants, laboratory exercises can be very fruitful. Most students have a preferred modality, usually visual, and the lecture-style presentations of most classes do not provide the best learning for visual and kinestetic learners. Laboratory exercises can prove very beneficial to both. This section will offer ideas and exercises for forage-related lab and field trip activities.

The activities are presented under the subject (weeds, hay, species identification, fencing). Each activity will include: objective, materials, procedure, lab report ideas, and educational strategies.

Subject: Yield

Objective: To help students determine yields; comparing estimation with square foot calculations

Materials needed: Outdoor pasture area, rulers or yardsticks, scissors, oven, bags (lunchbags),pencils, paper for notes, calculators, rising plate stick.

Procedures:

Introduction: Ask how much forage is in the pasture? How can we determine what is available for livestock? Brainstorm on how you might go about answering that question. Do you guess?

Input:

Not all the forage growing here is available to livestock. The lips, teeth, tongue, and jaws of the animals will determine how closely the animal can eat to the ground. Most cannot get closer than 1-2 inches and we should not want that. There are three main ways to determine how much forage is available for livestock. Some people take an estimation by how high the grass is to the boot. Write down your estimation. This may help determine when to rotate livestock but is not an accurate method for determining yield. Determining the yield of random square feet provides a more accurate yield. Select a square foot and clip the forage to 2 inches above the soil. Collect the cut forage in the bag. Repeat this for 3-4 squares. Dry the bags of forage clippings in an oven overnight at 300 degrees. Weigh an empty bag in grams. Weigh the bags of clippings. Subtract the weight of the bag to determine the dry matter weight of the forage for each sample. Average your results. Multiply the weight by the number of square feet in an acre, 43,560 square feet per acre. Convert the grams to to pound to tons. This will provide the available dry matter of an acre. Use the rising plate meter and other commercial devices to determine yield to show other, more accurate methods of determining yield.

Lab report ideas:

Laboratory reports provide the opportunity for students to apply what they have seen and done in the exercises to forage management decisions and place knowledge and skills into long-term memory. Present a few more opportunities to do the calculations on the lab report to shift the learning into long-term memory. The lab report may also include: List your estimated yield and your calculated yield. List the advantages and disadvantages of devices such as a rising plate meter. How can GIS capabilities help in determining yield? Research which animals can harvest feed closest to the ground. Discuss other considerations that should be included when determining yield (trampling, fouling, pugging).

Strategies:

This lab exercise may highlight weaknesses in calculations of some students. Observe the comfort level of the math portions of the exercise. Do several examples of the calculations visually and auditorially. A discussion on determining averages and cross canceling may need to be included. Help students memorize 43,560 square feet/acre since it will prove helpful in many forage-related calculations. All students should become aware that estimation is not the best way to determine yield. Compare and contrast the findings of various methods visually. Discuss the applications to livestock grazing, winter rations, hay and silage making.