THE BINDING FORCE OF ROOTS
Materials:An envelope of radish ormustardseeds from your local variety
store, florist or nursery, two papercups, abouttwo cups of rich soil.
Follow this procedure: Soak six seeds in water for several daysuntilthey
begin to sprout. (They are now called"seedlings.") Fill eachpapercup with
soil to aboutthree-quartersof itscapacity. Plantthe seedlings and let them
grow for two weeks. Careful! Waterthem sparingly.
You will observe:The extensiverootsystemsofthe seedlings. Try to pull
up ashoot. All, or most of the soil in the cups will come loose with the roots,
and the soil mass will have taken the shape of thepapercup.The rootsofplants hold down soil sothatit cannoteasily be blown away
by wind or washed away by rain orrunningwater. Thebindingforce of roots
preventserosion,the loss by wearing away of precious top soil.