Two good books, one about tulips and the other about the 182 outstanding species of trees in America, have been published recently.

"The Book of Tulips," by Tom Lodewijk, edited by Ruth Buchan (Vendome Press, distributed by Viking Press, 128 printed pages, $14.95).

This is mostly a history of the tulip, with descriptions of the many important varieties including photographs in full color. There are also easy-to-follow driections on how to care for them both in the garden and in the home.

We know the tulip originated thousands of years ago in an area that stretches from the coasts of the mediterranean well past the borders of China, says the author, but we know very little about its journey from a wildflower in China to a cultivated one in Constantinople.

The first tulips that came to the Netherlands, now the real home of the tulip, he says, were not wild flowers: they were highly cultivated, where the result of experimentation, expertise and experience.

It was during this period (1494 to 1566) that the bulb was tamed and cultivated for its shape and color, to give pleasure to the sultan and his entourage. At that time Constantinople had the reputation of being the most beautiful city in the world.

New varieties of tulips can come about as chance mutations (sports) or be created through the efforts of a bulb grower or horticulturist.

The breeder takes pollen from the anther of one variety and carefully implants it in the ovary of another, using tweezers or a small paintbrush. As soon as the seeds begin to swell, they are removed and planted with the utmost care and precision in small containers.

Once these modern procedures were established, the number of new tulip varieties increased dramatically.

At first the tulip was prized as a natural curiosity, but in later years it became a hobby for the extremely rich, who were able to maintain large gardens where they could experiment with exotic plants.

During the height of tulipomania in the 17th century, some tulip bulbs still in the ground sold literally for a fortune -- thousand of dollars each.

Bulbs need a very well-drained soil, the author says. They should be planted at least 5 or 6 inches deep, depending on the kind and size of the bulb.

Those that are planted much deeper -- up to 12 inches -- will continue to bloom for several years more than those planted at a more shallow depth.

There is another reason for deep planting. Mice and other rodents are particularly fond of tulip bulbs. The deeper the bulbs, the less available they are to the chipmunks, moles and mice.

One more reason for deep planting is that it permits the planting of spring and summer flowering plants over the tulips.

The dead tulip flowers should be cut off to prevent the forming of seeds, which would deplete the energy in the bulb. The tulip foliage must be allowed to die before being cut off. This gives the bulb food for next season's bloom.

The danger of deep planting is that the bulbs will rot if the soil is poorly drained.

It is best not to plant tulips in the same bed year after year. Most of the nourishment of the soil will have been used up.

Lodewijk, the author, is said to be one of Holland's leading experts on tulips. Buchan, the editor, for many years was editor-in-chief of Doubleday's Garden Guide.

"Knowing Your Trees," by G. H. Collingwood and Warren d. Brush, revised and edited by Devereux Butcher (The American Foresty Assn., distributed by Scribner's, 387 printed pages, $14.95).

This is a revised and enlarged edition of a book first printed in 1937.

Each of the 182 outstanding trees' characteristics and contributions to society are described, focusing on the botanical features, the range, the uses and economic importance of each tree so that you will be able to recognize the forest and the trees.

The simple but comprehensive text is augmented with more than 900 illustrations and photographs of each sample tree's summer silhouette, as well as its leaf, bark, flower and fruit; in addition, winter silhouettes are included for all deciduous trees. A map showing where each kind of tree grows provides geographic orientation.