2.  Osage orange (Toxylon pomiferum)

    Very hardy.  Plant close.

3.  English hawthorn (Crataegus oxyacantha)

    Flowers beautifully and grows in compact masses.  Plant close.

4.  Lombardy poplar (Populus nigra var. italica)

    Forms a tall screen and grows under the most unfavorable conditions. 
    Plant 8 to 12 feet apart.

Quality of trees:  Trees grown in a nursery are preferable for
    transplanting to trees grown in the forest.  Nursery-grown trees
    possess a well-developed root system with numerous fibrous rootlets,
    a straight stem, a symmetrical crown, and a well-defined leader. 
    Trees grown in neighboring nurseries are preferable to those grown
    at great distances, because they will be better adapted to local
    climatic and soil conditions.  The short distances over which they
    must be transported also will entail less danger to the roots
    through drying.  For lawn planting, the branches should reach low to
    the ground, while for street purposes the branches should start at
    about seven feet from the ground.  For street planting, it is also
    important that the stem should be perfectly straight and about two
    inches in diameter.  For woodland planting, the form of the tree is
    of minor consideration, though it is well to have the leader well
    defined here as well as in the other cases.  See Fig. 95.

When and how to procure the trees:  The trees should be selected in the
    nursery personally.  Some persons prefer to seal the more valuable
    specimens with leaden seals.  Fall is the best time to make the
    selection, because at that time one can have a wider choice of
    material.  Selecting thus early will also prevent delay in delivery
    at the time when it is desired to plant.

When to plant:  The best time to plant trees is early spring, just before
    growth begins, and after the frost is out of the ground.  From the
    latter part of March to the early part of May is generally the
    planting period in the Eastern States.

    Where one has to plant both coniferous and deciduous trees, it is
    best to get the deciduous in first, and then the conifers.

How to plant:  The location of the trees with relation to each other
    should be carefully considered.  On the lawn, they should be
    separated far enough to allow for the full spread of the tree.  On
    streets, trees should be planted thirty to thirty-five feet apart
    and in case of the elm, forty to fifty feet.  In woodlands, it is
    well to plant as close as six feet apart where small seedlings are
    used and about twelve feet apart in the case of trees an inch or
    more in diameter.  An abundance of good soil (one to two cubic yards)
    is essential with each tree where the specimens used are an inch or
    two in diameter.  A rich mellow loam, such as one finds on the
    surface of a well-tilled farm, is the ideal soil.  Manure should
    never be placed in direct contact with the roots or stem of the
    tree.