Soils, 5, 23.
    adobe, 30.
    alfalfa, 29.
    and the farmer, 5.
    attitude of toward water, 40.
    cabbage, 28, 161.
    canteloupe, 28, 161.
    capacity for film water, 51.
    cauliflower, 28.
    classified, 26.
    clay, 29.
    cloddy, 38.
    close, 38.
    coarse, 38.
    compact, 38.
    corn, 28, 29, 30, 161.
    cotton, 28, 29, 161.
    effect of working when wet, 26, 41.
    egg plant, 28.
    fine, 38.
    forest, 29.
    fruit, 27, 29.
    general farming, 28, 29.
    grain, 28, 162.
    grass, 28, 29, 162.
    gravelly, 29.
    hard, 38.
    hay, 29, 30.
    heavy, 38.
    how made, 30.
    humus, 27, 38.
    leachy, 38.
    loamy, 28.
    loose, 38.
    lose heat, 59.
    light, 38.
    lime in, 67, 149.
    loss of water from, 53, 153.
    lumpy, 38.
    mellow, 38.
    oat, 29.
    open, 38.
    organic matter in, 220.
    pasture, 30.
    pea, 28.
    peat, 30.
    peppers, 28.
    plant food in, 63.
    potato, 28, 29, 161.
    porous, 38.
    relation of to water, 39, 46.
    relation of to plants, 23.
    retentive, 38.
    rhubarb, 28.
    sandy, 27.
    small fruit, 28, 29.
    soft, 38.
    sorghum, 162.
    stiff, 38.
    stony, 29.
    strawberry, 28.
    swamp, 30.
    testing, 162, 215.
    tobacco, 27.
    tomato, 28, 161.
    truck, 27, 28, 29, 161.
    vegetable, 28.
    water-absorbing power of, 40, 43, 46, 142.
    water-holding power of, 44, 142.
    watermelon, 28, 161.
    wheat, 29, 30.

  Soil water, 150, 151.
    amount of used by plants, 40.
    and farm operations, 156.
    control of, 53.
    form of, 48, 153.
    greatest factor in growth of crop, 46.
    importance of, 39, 151.
    loss of, 53, 155, 157, 164.
    loss of by evaporation, 54.
    loss of by weeds, 54, 165.
    loss of by surface wash, 53.
    necessity for, 151.
    not enough, 154.
    saving, 165.
    sources of, 40, 153.
    too much, 154.

  Soil water influenced,
    by cropping, 159.
    by harrowing, 101, 103, 158.
    by humus, 42, 43, 44, 45, 220.
    by plowing, 91, 156.
    by ridging, 98, 158.
    by rolling, 106, 158.

  Sorghum soils, 162.

  Soy-bean, as a green manure crop, 189.
    growth of roots, 12.

  Spade, 90.

  Spading, 90.

  Spading-fork, 90.

  Spike-toothed harrows, 102, 104.

  Spraying, 118.

  Spring plowing, 98.

  Spring-toothed harrows, 102, 103.

  Squash flowers, 133.

  Stable manure, 171, 173.

  Stamen, 129.
    function of, 131.

  Staminate flowers, 133.