This section is from the book "A Few Suggestions On Tree Planting", by C. S. Sargent.
When the nature of the soil will permit, shallow furrows four feet apart should be run one way across the field to be planted. This is best done during the autumn previous to planting. Then by planting in the furrows, and inserting the plants four feet apart in the rows, the whole land will be covered with plants standing four feet apart each way. Planted at this distance 2,720 plants will be required to the acre. On hilly, rocky land, which is especially recommended for the cultivation of the European larch, and where it is impossible to run furrows, it will be only necessary to open with a spade holes large enough to admit the roots of the plants, care being taken to set them as near four feet apart each way as the nature of the ground will admit. In very exposed situations on the sea-coast, it is recommended to plant as many as 5,000 trees to the acre, the plants being inserted more thickly on the outsides of the plantations in order that the young trees may furnish shelter to each other.
It is imperative to plant the Larch as early in the season as the ground can be worked. No other tree begins to grow so early, and if the operation of transplanting it is delayed until the new shoots have pushed, it is generally followed by the destruction of the plant.
The Scotch and Corsican pines can be planted up to the 1st of May.
Land in condition to grow corn or an average hay-crop is suited to produce a profitable crop of white ash. Deep, moist land, rather than that which is light and gravelly, should be selected for this tree. The land should be ploughed, harrowed, and made as mellow as possible during the autumn previous, that the trees may be planted as soon as the ground can be worked in the spring.
As soon as the frost is out mark out the field with furrows four feet apart, and insert the trees two feet apart in the rows. This will give 5,445 plants to the acre, which, at the end of ten years, must be thinned one half. These thinnings are valuable for barrel-hoops, etc.
It is recommended to cultivate between the rows for two or three years to keep down the weeds and prevent the soil from baking. At the end of that time the ground will probably be entirely shaded by the trees, and further cultivation will not be necessary.