Now that the Christmas trees at Rockefeller Center and on the Ellipse are lighted, it's time to discuss how to select a tree for your home.

Choosing a tree depends on many factors, including species, cost, user-friendliness and freshness.

Artificial trees are a possibility, but I'm biased. Fabric-covered wires can't capture the season the way the real deal does. Not even spraying on a pine scent can convince me that artificial should replace cut or, better yet, live Christmas trees.

Here is information about some types of trees:

* Douglas fir (Pseudotsuga menziesii): This is more closely related to hemlock than fir. It has the least tendency to shed and can often be more expensive than other varieties. If fresh and shaken to remove dead needles, Douglas fir will hold its soft needles exceptionally well, making it a clean guest in your house. If you can find a 10- to 12-foot or taller specimen with a lot of branches, it will make a magnificent, graceful display in an atrium or a house with a high ceiling. Douglas fir will almost fold into your trunk or lie flat on your car roof for easy transport from the lot. Most grow straight as an arrow and are well-balanced for easy setup.

* White fir (Abies concolor): This is my favorite. It holds its needles the best of all firs. When you cut the trunk, you'll discover another desirable trait: its pleasant citrus fragrance. Keep the base you cut from the tree; place it near heat, on foil, for a couple of days for added fragrance. When in the presence of a white fir, in nature or in someone's living room, I am compelled to pull off a needle and bruise it for its superb aroma. The tree matches the color of the blue spruce, but is soft to the touch. These trees are not as evenly branched as others, leaving you little openings, nooks and crannies for decorations. Be careful taking this one home. You might snap a few limbs putting it on your car roof or into the trunk.

* Fraser fir (Abies fraseri): This is my second-favorite Christmas tree. It is easy to handle and transport, and soft to the touch. The open habit decorates well. On some branches, you can hang trimmings all the way to the trunk. Michael Dirr writes in his Manual of Woody Landscape Plants that the fraser is the Cadillac of Christmas trees. Growers are meeting the need. On farms in North Carolina alone, Dirr estimates, there are about 75 million of them.

* Scotch pine (Pinus sylvestris): This old standard matures quickly and shears into shape easily. It is generally inexpensive. Beware of crooked trunks and lower limbs that grow up through the tree. Taking them off can ruin the shape. Before buying, look carefully. Pull branches down to see what the tree will look like pruned. This tree holds its needles relatively well. Of all pines, it has the most widely distributed native habitat. It grows in Norway, Scotland, Spain, Asia and Siberia and has naturalized in some areas of New England. Scotch pines might have been some of the earliest Christmas trees. They can have needles 1 to 3 inches long and range in color from blue-green to deep-green to an undesirable yellow-green.

* White pine (Pinus strobus): For those who like lacy, airy plants, this is the tree. It can be wide-spreading, but lights show through beautifully. It is among the most attractive pines for color, texture and habit. White pine is soft to the touch with long, thin needles. If fresh, they will hold through the holiday season. The tree is at its best aesthetically with just a few decorations and strands of small white lights that shine from the inside. It will drop some needles by New Year's Day, so keep it over a blanket or a plastic cover. The Eastern white pine is native to our region. It transplants well.

* Blue spruce (Picea pungens var. glauca): This fragrant tree has a classic Christmas-tree shape. The stiff habit holds decorations beautifully and the clear blue needles are exceedingly handsome. Wear gloves to handle it, because the needles are sharp. It doesn't hold the needles exceptionally well; they are usually dropping by New Year's Day. Rigid branches and sharp needles make a large specimen difficult to transport without a pickup truck. You will need gloves to decorate it.

If you prefer a live tree, go to a garden center. Trees are sold balled and burlapped or in a large basket or pot. I would prepare the planting hole now. Put the soil in the garage to keep it from freezing. Bring your tree in on Dec. 24; keep the root ball moist. Put the tree back in the garage as soon after Christmas as possible. Plant the first nice day after tree has been in garage for seven days.

Joel M. Lerner is president of Environmental Design in Capitol View Park, Md. His e-mail address is jml@gardenlerner.com; his web page is www.gardenlerner.com

Douglas firs grow straight, are well-balanced, do not shed much and can be costly.