Loamy soils, 28.

  London purple, 117.

  Loss of soil water, 53, 155.

  Lucern, 13.
    roots, 13.

  Magnesium in plants, 66.

  Maintenance of fertility, 150.

  Materials composing soils, 26.

  Mallow family, 86.

  Manures, barn, 171, 173.
    application of, 177.
    care of, 173.
    checking losses from, 176.
    effect on soil texture, 172.
    effect on soil water, 159.
    functions of, 171.
    losses from leaching, 173.
    losses from heating, 174.

  Many things the farmer deals with, 5.

  Marigold, 6.

  Marl, 201.

  Melon flower, 133.

  Miami sand, 28.

  Microscopic organisms, 5.

  Mixed fertilizers, 202.
    inflating the guarantee, 204.
    low grade, 204, 207.
    many brands, 202.
    valuation of, 205.

  Morning-glory, 129.

  Most important factor in the raising of crops, 151.

  Mould board of plow, 94.

  Muck, swamp, 30.

  Mulch, soil, 56.
    how made, 56.
    to save water, 56.

  Muriate of potash, 199.

  Mustard, family, 86.
    flower, 129, 130.

  Muskmelon soils, 161.

  Night shade family, 86.

  Nitrates, what they are, 146.
    availability of, 146, 193.
    solubility of, 146.

  Nitrate of soda, 193.
    nitrogen, 193.

  Nitric acid in soil, 146.

  Nitrification, 146.
    aided by plowing, 146.
    aided by lime, 146.
    conditions favorable to, 146.

  Nitrifying germs, 144, 145.

  Nitrogen, 66.
    added to the soil by legumes, 68.
    grown on the farm, 68.
    in humus, 167.
    in soils, 67, 148.
    in plants, 66, 67.
    in fertilizers, 192.
    loss of, 67.
    sources of, 171.

  Nitrogen-fixing germs, 144.

  Non-leguminous green manure-crops, 191.

  Norfolk sand, 28.

  Oats, soil for, 29.

  Object of this book, 3.

  Odorless phosphate, 198.

  Oil in plants, 64, 66.

  One-crop system, 221.
    effect on fertility, 221.

  Onion, 6.

  Organic matter,
    in soils, 32, 62, 220.
    value of, 61.

  Osmose, 18.

  Ovary of flower, 130.

  Ovules, 130.

  Oxygen in plants, 66.

  Paris green to destroy chewing insects, 117.

  Parsley family, 86.

  Parsnip root, depth of growth, 13.

  Parsnips, 4.

  Pasture, soils for, 30.

  Pea family, 86.
    soils, 28.

  Peach borer, 127.
    flower, 130.

  Peanuts, 5.

  Peat, 30.

  Peppers, soil for, 28.