Usefulness of Irrigation
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Gloria T. Bond Coles School
8441 S. Yates Ave.
Chicago IL 60617
To show that water is necessary for plant growth.
To show how a dam can turn a nearly useless water way into a valuable form
Lima beans Lima beans
Dry soil Soil
Paper cups Paper cups
2 plastic straws Plywood 36 x 30
2 catch pans
2 flexible tubes
Attempt to grow the lima beans in very dry soil. After 7 days, plant some
more lima beans in very rich soil and water regularly. Compare the beans in
size and growth development. Keep a growth chart.
To construct the dam, cut pieces of 1/4 inch plywood according to following
dimensions; front piece 36 inches long, 6 inches high, 6 inches wide, cut 2
angles 9 inches from each end and 2 inches above the base. To construct the
back piece, cut 36 inches long, 12 inches high, 12 inches wide, 2 angles 8
inches from each end and 8 inches above base. Cut 2 side pieces, 30 inches
long, 12 inches high slanting from 12 inches to 6 inches. Cut 4 top pieces, 33
inches long and 10 inches wide. Nail the front, back and sides together. Caulk
joints. Cut triangle piece for dam. Drill 2 holes in the triangular piece same
size as straws. With a straight pin, punch holes along one side of each of the
two straws. Plug one end of each straw. Push the other end through the dam.
Set a pail of water on a platform behind the model. Put the 2 flexible tubes in
the pail and let water run slowly into the troughs. Water will flow right out
of the trough without a dam. A lake will form behind the dam and the irrigation
pipes will take water to dry areas for watering of the soil.
Plants must have water in order to grow. Through irrigation pipes, water
can be directed to dry areas where it is needed as long as there is a source of
water such as a dam.