Early spring is one of the best times to plant and transplant deciduous trees and shrubs (those that drop their leaves in the fall). Evergreens - such as pine, spruce and hemlock - can be planted in late summer and early fall; American holly and magnolia in mid-to-late spring.

The big advantage of late summer and early fall planting of evergreens is they have a longer time in which to develop a root system in the new location before having to cope with the heat and drought of summer.

Tt also is important for them to have time enough to make some root growth before winter; otherwise they may suffer winter injury.

In areas where winter comes early, it is best to wait until spring to plant and transplant evergreens.

Many of the trees and shrubs available at nurseries today are in containers and may have been in them a year or two or longer. The roots of well-grown plants will almost entirely fill the container. There will be a clearly visible surface of roots on the root ball when it is removed from the container.

It is essential to break up such root balls before planting. Otherwise the roots will not grow outward into the adjoining soil and the plant most likely will die within two or three years, according to specialists.

Don't plant the tree deeper than it was growing before. After planting, the top of the root ball should be 2 or 3 inches above the soil level to allow for settling.

Do not mound up soil around the trunk after planting. If you do, water will run off instead of entering the soil where the roots are, and roots also will have more difficulty getting oxygen. It is best to have a depression (saucer) around the trunk to hold water when it is supplied.

Do not apply a mulch until the earth gets good and warm. The mulch would keep the soil from warming up and delay the tree in making new root growth.

Eliminate grass from a circle 10 to 12 feet in diameter around the tree if it is planted on the lawn. To grow and increase in length, the roots would have to invade soil already occupied by grass roots. There would be competition for space, moisture and nutrients.

Don't prune the young tree any more than necessary the first few years after planting. A young tree left completely unpruned, except for the removal of dead wood, will grow faster than if it is pruned at any time by any method. Even the leaves that grow along the trunk help produce food for the tree.

The newly planted tree should be watered regularly during the first three or four summers when there is less than an inch of rainfall during the week. It will take that long for it to establish a root system adequate to carry it through a period of dry weather.

Young trees should be fertilized every year unless the soil is so rich that it is unnecessary. When they are making less than 4 to 6 inches of twig growth and the foliage is thin, they should be fertilized.

The slow growing kinds, such as the oaks and some of the maples, can be stimulated by fertilizing and watering to grow almost as fast as the so-called fast-growing kinds such as silver maple, box elder and ailanthus.