Regardless of yard size, trees are destined to be part of our landscape. I'll write later about shade trees that are more suited to our climate, soils and other environmental factors. Right now, you should be aware of the hazards of choosing trees you consider to be dual-purpose - trees that will provide you with needed shade plus a bountiful fruit crop.

Generally speaking, you should not consider a fruit tree as the source to shade the west side of the house, cool a patio or cover the children's play area. A fruit tree for gardeners needs to be kept to the size where it can be easily picked, pruned and applied with pest control sprays. Commercial orchards are in a different category.Apples are the most widely planted fruit tree in our location. You can choose from scores of varieties in hues of yellow, red or green with ripening times from July to November.

For a list of recommended fruit and nut varieties, send a long envelope with your name and two stamps on it to USU Extension Service, 2001 S. State St., Rm. S1200, Salt Lake City, UT 84190-3350. Ask for "Guide to a Successful Backyard Garden in Utah."

You put a lot of thought into choosing which variety, but few folks properly consider the other half of the tree. After all, the roots are out of sight under the ground. An orchardist wouldn't think of planting a tree on an unknown rootstock. The hobbyist should be aware that the root onto which the desired variety is grafted has a tremendous influence on tree performance. Many nursery outlets themselves don't know which specific root they sell. You are told a tree size rating: standard (full size), semi-dwarf or dwarf. The latter two are relative depending on a lot of factors over which you have no control. It's the tree that turns out dwarfed, not the fruit.

For that limited area in which you want food to grow on trees, the dwarf apple is the best choice. Yellow Delicious seems to be well-suited to dwarfing rootstocks and is a very popular apple that does well here. If you can specify, M26 is a rootstock that should produce an 8-to-14-foot tree. M27 or M9 root will allow a tree to grow only 6 feet or so tall. These roots lack vigor and you should support them with a stake or trellis. Space can be more fully utilized by special training techniques such as espalier.

You can grow apples along a fence if you have dedication to detailed pruning during the entire year, not just in the spring. If that approach to tree fruits appeals to you, I'd suggest you learn more about it in either the HP Book "Western Fruits, Berries and Nuts" or the Ortho Book "All About Growing Fruits & Berries."

The M7a is the most popular semi-dwarf rootstock. The final size of the tree is about 12-16 feet. The ultimate height of the tree depends not only on the rootstock but also on the variety, soil conditions and tree care.

MM106 or 111 are less dwarfing and will be about 70-75 percent the size of a standard tree.

I get quite a few calls each year from people wanting to save an apple variety where the mature tree is dying or has to be removed for some reason. Apples don't grow well from cuttings and seed doesn't produce fruit the same as the parent tree. Grafting a twig (scion) to another tree is the best solution. A small scion doesn't compete well in a large established tree. Most nurseries don't carry rootstocks, so until recently, I had to recommend buying an apple tree and removing its top to graft on the valuable variety.

Now there are nurseries that cater to supplying rootstocks for the hobby fruit grower. I have catalogs from Raintree Nursery, 391 Butts Road, Morton, WA 98356 and Northwoods Nursery, 28696 S. Cramer Road, Molalla, OR 97038. They have rootstocks that you can purchase to do your own grafting. The list includes M26, M7a, M27 for apples plus pear, plum and cherry rootstocks.

I'm spending some time in the dead of winter talking fruit trees for a couple of reasons:

1. You may have to shop around to get the combination of variety and size controlling rootstock for your family's need. The shopping may include mail order catalogs if you can't find what you want at local nurseries. The earlier you get your bare root trees planted after the soil can be prepared, the better will be their chance for survival.

2. If you're going to do some grafting, gather the scion wood this month. Cut 12- to 18-inch lengths from vigorous twigs that grew in 1988. Slightly larger than pencil diameter is about right. Wrap them in moist toweling, put them in a plastic bag and store them at 32-40 degrees. The vegetable bin of the refrigerator is about right. We'll talk more about grafting when the time nears to do the job. Apples graft easily.

Apples are the most suitable tree for dwarfing. Pears dwarfed on quince root have some problems but are readily available. A more compatible alternative is Old Home X Farmingdale, but it is not as widely used as yet. You can buy them from the above nurseries.

Stone fruits are offered as dwarf trees in nurseries and catalogs. Peaches can be kept in bounds with proper pruning so a special root is not needed. Plums and prunes are somewhat larger but still can be managed.

Cherries and apricots are the largest of our fruit trees and aren't suited completely to the small yard. Dwarf selections may be purchased, but past experience has shown that poor growth and graft incompatibility are common.

There is no need to grow fruit that can't be harvested in good condition. The tree should be pruned from the same ladder from which you pick so you'll be able to reach the fruit.

1. Fruit trees can be managed with proper pruning. We'll have three demonstrations in March to show those techniques. Refer to last week's column or watch this space for their location. They're free.

2. Without braving the outside weather, our Tree Fruit Workshop will illustrate correct growing and pruning practices. It will be Feb. 21 at the Granger Bishop's Storehouse, 3628 W. 72nd South at 7 p.m. On Feb. 22, choose from a 2 or 7 p.m. session at the Extension Service Training Room S1007, 2001 S. State St. Free.

3. Learn how to do your own grafting to have suited varieties on known rootstocks. March 21, 2 or 7 p.m. Extension Service Training Room listed above. $2 material fee. Call 468-3170 to reserve a place.

The KSL Greenhouse has started for the year. KSL Radio, 1160 on the AM dial, each Saturday morning, 8:36. Larry Sagers co-hosts with garden experts as guests.

KTKK "Growing Concerns" continues at 8 every Saturday morning. Duane Hatch answers phoned-in questions. 630 on the AM dial.

KUTV, Ch. 2 - Duane Hatch presents gardening tips during the noon news each Monday and Friday

Last week's column omitted the Lawn Care Workshop in our series. It will be on March 28 and 29, just before "More Vegetables" on April 4 and 5.