Cucumber flower, 133.

  Cultivation. 
    (See After-cultivation.)

  Denitrification, 147.
    conditions favoring, 147.

  Denitrifying germs, 144, 147.

  Draft ring of plow, 93.

  Draining, need of, 235.

  Drains, 158-239.
    and capillary water, 237.
    covered, 237.

  Drains, effect on film water, 237.
    effect on plant food, 238.
    effect on soil temperature, 238.
    effect on soil water, 237.
    grade of, 239.
    lateral, 239.
    location of, 238.
    main, 239.
    open ditch, 237.
    surface, 237.
    tile, 239.

  Dried blood, 194.
    as a fertilizer, 194.
    nitrogen in, 194.

  Early crops, soils for, 27, 28.

  Egg experiments to show osmose, 18, 19.

  Egg plant, soil for, 28.

  Elements in plants, 66.

  Elm tree leaf beetle, 117.

  Endosperm, 78.
    use of, 79.

  Epicotyl, 78.

  Essential organs of flowers, 131.

  Evaporation, loss of water by, 54.
    loss of heat by, 59.

  Excursion,
    to examine soils, 24.
    to see plow cutting roots, 14.
    to study roots, 11.
    to study leaves, 108.
    to study stems, 120.
    to visit farm, 4.

  Experiment to show,
    air necessary for germination, 73.
    amount of transpiration, 110.
    capillarity, 49.
    capacity of soils for film water, 51.
    checking loss of water by evaporation, 55.
    chlorophyl necessary for starch making, 113.
    effect of soil mulch, 55.
    depth of planting seeds, 81.
    effect of lime on clay soil, 42.
    effect of working soil when wet, 26, 45.
    exclusion of oxygen by leaf, 113.
    film water, 50.
    growth in length of roots, 16.
    heat necessary for germination, 73.
    how food and water get into the root, 18, 19.
    how soils are warmed, 58.
    how soils lose heat, 59.
    importance of roots, 7.
    moisture necessary for germination, 71.
    no starch formed in dark, 112.
    osmose, 18, 19.
    plants contain albuminoids, 64.
    plants contain ashes, 65.
    plants contain cellulose, 63.
    plants contain gum, 64.
    plants contain oil, 64.
    plants contain starch, 64.
    plants contain sugar, 64.
    plants contain water, 65.
    power of soils to absorb rain, 40.
    power of soils to hold water, 44, 45.
    power of soils to pump water, 43.
    roots absorb moisture, 9.
    roots take food from soil, 9.
    roots produce new plants, 10.
    roots need air, 21.
    soil characteristics, 24, 25.
    soil temperature, 57, 60.
    starch in leaf, 111.
    stems carry sap, 122.
    stems store food, 124.
    transpiration, the fact, 109.
    transpiration, amount, 111.
    use of cotyledons, 79.
    what becomes of water taken by roots, 39.