Jody Krisky, age 9, of Staten Island, N.Y., for her question:

WHY IS IT SO HARD TO CATCH TROUT?

In summertime, when vacations are usually scheduled, many people turn their thoughts to trout fishing. There's no better way to relax and let the world go away, millions agree,

than to drop a fishing line into a river, stream or lake and wait patiently for the strike of a beautiful  and delicious  trout. Ah, that's living.

The fact that trout aren't too easy to catch, most fishermen agree, is part of what makes them so wonderful. They are classified as game fish, and being difficult to catch is part of their makeup.

Trout like to live in cool, clear waters where the bottom is gravel covered. They spawn in fall or early spring and the eggs hatch when the temperature of the water goes up late in spring. During winter some of the fish go downstream and into the open sea. This is especially true of the salmon, a fish that is closely related to true trout.

Trout fall into two main groups: the chars and the true trout.

Chars include the brook or speckled which can be found from the Appalachian regions westward to the Great Lakes and Minnesota, in Canada from Labrador to the Saskatchewan River and in lakes and streams of the Upper Mississippi Valley and the Western States. Largest ever caught weighed almost 15 pounds and was from the north shore of Lake Superior.

Lake trout are also chars. They're much larger than the brook trout. They often weigh in between 15 and 20 pounds with an occasional fish coming in at 100 pounds.

True trout include the rainbows of western North America. They are especially hard to catch, and often an angler must change lines, hooks and bait to get the right combination. Also, they often fight hard and long for their freedom once they have been hooked.

Another true trout is the cutthroat. Much like the rainbow trout, it is a good fighter and excellent to eat. It has a brilliant red streak on each side of his jaw and can be found along the northwestern coast and throughout the Rocky Mountain region.

In California, the golden trout is the official state fish. It can be found in mountain waters through much of the western part of the United States.

Another true trout  and one that is as hard to catch as most of its relatives  is called the brown trout. It is actually a native of Europe but was brought to the streams and lakes of the United States and parts of Canada. Some fishermen like the brown trout while others do not rate him as high as other North American trout.