Seed seeds of leguminous trees should be scalded in order to get good results. This applies to the black, yellow and honey locust and the coffee tree. To do this successfully, the seed should be placed about one inch deep in a large milk-pan or similar vessel and hot water (130° to 160° Fahr.) poured over them, perhaps three inches deep. This should be allowed to stand until cool, when it will be found that some of the seeds have swollen. These should be picked out and the remainder treated again with hot water, and the process repeated until all have swollen. Seedlings of this class are managed in much the same way as those of ash and maple.
Seed planting (Figs. 466-469).— Seeds may be classified into three groups : (1) deciduous -tree seeds that ripen in spring and early summer ; (2) deciduous-tree seeds that ripen in autumn ; (3) coniferous-tree seeds.
Among the seeds that ripen in spring and early summer are soft and red maple, the elms, cotton woods and willows. These should be gathered as soon as ripe, and, with the exception of the red elm, should be sown in a few days or weeks, as they retain their vitality but a short time. Red elm seed will not grow until the following spring.
The thousands of seedlings of cottonwood, elm and soft maple that naturally spring up along the sand-bars and river and lake shores, show what are the best conditions for the germination of these seeds, but seeds of white elm and soft maple generally do well when sown in any good garden soil. Cottonwood seedlings can be grown by scat tering branches bearing unopened seed-pods along the furrows in moist soil and covering the seed lightly, when they will shell out ; but they are of such uncertain growth that most nurserymen depend on the sand-bars and lake shores for their supply.
Willows are seldom grown from seed, as these are difficult to raise, and the trees start easily from cuttings. Elm, soft maple and mulberry seeds generally grow well on any good moist soil, but that which is somewhat sandy is best. They should be sown thickly in drills eight inches wide and three feet apart, when they may be easily cultivated by a horse cultivator. Or they may be sown in rows sixteen inches apart and culti vated by hand. Elm and soft maple seed should be covered about three-fourths inch, mulberry about one-fourth inch and soft maple about one inch. If the weather is dry at the time the seed is sown, the soil over the seed should be thoroughly firmed, and if the weather continues dry the rows should be watered. Watering, however, is seldom necessary on good retentive land, if the soil has been prop erly packed. When watering is resorted to, it is a good plan to cover the drills lightly with some mulch or litter, or shade them with boards, but these should be removed as soon as the seed lings first appear. With proper conditions, seeds so
planted will start quickly and grow rapidly. The seedlings of soft maple and white elm will gen erally be large enough for transplanting to the young forest or windbreak the first season ; how ever, they may be allowed to grow another year in the seed-bed without injury, but should generally be transplanted before the growth of the third year begins.
The seeds of deciduous trees that ripen in autumn may be sown to advantage at that time, provided the soil is such that it will not pack too firmly, or when the seeds are not liable to be washed out or eaten by rodents or other animals. Our most successful nurserymen generally prefer to sow such seeds in autumn, and they aim to bring about the conditions that make it successful, but good results also generally follow the early sowing of such seeds in the spring. The distance between the rows, and the covering, should be the same as recommended for elm seedlings.
It is important to keep the soil loose and mellow between the seedlings, and to keep the weeds very carefully removed until at least the middle of July, after which they may sometimes be allowed to grow to advantage to afford winter protection ; but in the case of very small seedlings this protection is best given by a light mulch, put on in autumn and taken off in spring. The weeds should be kept out.
If the seeds of red cedar, black thorn, mountain ash and others that require a long time to start are sown in the spring and do not germinate, it is a good plan to cover the bed with an inch or two of hay or leaves to keep out weeds, and let this mulch remain until the following spring, when the seeds will probably be in condition to grow. The mulch should then be removed.
Quantity to sow.—The proper quantity of seeds of deciduous trees to sow in nursery rows depends very much on the kind and quality of the seeds and the soil in which they are to be sown. As a rule, thick sowing is better than thin sowing. The seeds of box-elder, ash and maple should be sown at the rate of about one good seed to the square inch; elm and birch should be sown twice as thickly. Plums and cherries sown in drills should be allowed about one inch of row for each good seed. Black walnut, butternut, hickory and similar seeds should preferably be planted three or four in a place, where they are to grow, and all but one seedling cut out when several years old. If sown in drills, they should be placed three to six inches apart. Rather thick seeding does not seem to be any great hindrance to the making of a sufficient growth by seedlings of most of our broad-leaved trees the first year, but if left thick in the seed-bed the second year they are often seriously stunted.