Oak, —­, black, —­, pin, —­, red, —­, scarlet, —­, swamp white, —­, white, —­, yellow, Oaks and chestnut, Observations about trees, general, —­ and precision, child training in, Obtuse Japanese cypress, Opposite branched trees, Orange, Osage, Oriental spruce, —­ sycamore, Osage orange, Ostrya virginiana, Outdoor lesson on trees, Oyster-shell scale,

Paper birch,
Picea canadensis,
—­ excelsa,
—­ mariana,
—­ orientalis,
—­ parryana,
—­ pungens,
Pignut hickory,
Pin oak,
Pine, Austrian,
—­, Bhotan,
—­, Mugho,
—­, red,
—­, Scotch,
—­ trees,
—­ weevil, white,
—­, white,
Pines,
Pinus Austriaca,
—­ excelsa,
—­ mughus,
—­ resinosa,
—­ rigida,
—­ strobus,
—­ sylvestris,
Pitch pine,
Pith,
Plane or sycamore tree,
Plant lice, or aphides,
—­ study, value of, for children,
—­ trees, how to,
Planting forests,
—­ forests with seedling trees,
—­ little trees, methods of,
—­, improving woodland by,
—­ new trees,
—­ trees,
—­ —­ most economical method,
—­ —­ on land unsuitable for crops,
Plants, adaptation of, to seasonal changes,
Platanus occidentalis,
—­ orientalis,
Polyporus betulinus,
Poplar, balsam,
—­, Carolina,
—­, Lombardy or Italian,
—­, silver,
—­, tulip,
—­, white,
—­, yellow,
Populus alba,
—­ balsamifera,
—­ deltoides,
—­ grandidentata,
—­ nigra,
—­ tremuloides,
Pores in wood,
—­ small or indistinct,
—­ varying in size,
Poster for private woodlands,
Precautions against fire,
Protection against fungi and insects,
Pruning forest trees,
—­ lawn trees,
—­ shade trees,
—­, tools used in,
—­, too severe,
—­ trees, fundamental principles,
—­ —­, time for,
Pussy willow,

Quaking aspen,
Quality of trees, how to judge,
Quality of wood, how to judge,
Quercus alba,
—­ palustris,
—­ platanoides,
—­ rubra,
—­ velutina,

Red cedar, —­ —­ and arbor-vitae, description of, —­ gum, —­ horsechestnut, —­ juniper, —­ maple, —­ mulberry, —­ oak, —­ pine, —­ or black oaks, —­ or sweet gum, Red spider, Redwood, Removal of dead and broken branches, —­ of trees, how to mark, Requirements of trees, Retinospora obtusa, Rhytisma acerinum, Ring-porous woods, Robinia pseudacacia, Rock maple, Roots, —­, development of, —­, protection of, from drying, Rust, apple,

Safeguarding forests,
Salix babylonica,
Salix discolor,
Saperda vestita,
Sapwood,
Sawfly,
Scale, cottony-maple,
—­, oyster-shell,
Scale-like leaves,
Scarlet oak,
Sciadopitys verticillata,
Scolytus quadrispinosus,
Scotch pine,
Screening trees,
Season, influence of,
Seasons for spraying trees,
Seedling trees, planting forests with,
Shade trees, pruning,
Shagbark hickory,
Shellbark hickory,
Silver maple,