If you're thinking about buying your first canoe, the thing to think about first is what you're going to use it for, and where.

"That's the first question I ask a new buyer," said Brad Reardon of Springriver Corporation. "Then I ask how many people the canoe will be expected to carry.

"We try to get people to focus on what they want. Do they want to use it to fish or hunt, to paddle their children up and down the C&O Canal, to take a long wilderness camping trip, or are they interested in getting into whitewater paddling?"

Reardon points out that most canoeing around Washington is on rivers and that even the placid ones are fairly rocky, making aluminum or plastic hulls generally the best choices. Rocks eat fiberglass hulls.

Royalex ABS plastic hulls, hardly heard of ten years ago, have overtaken the once- standard Grumman aluminum boats and now dominate the canoe market. Royalex is the trade name for Uniroyal's sandwich of ABS foam and vinyl, lighter than aluminum but heavier than fiberglass.

ABS is quiet, forgiving and tough. The Old Town Canoe Company advertises its ABS hulls by showing one before and after it has been wrapped around a bridge abutment and then thrown off the factory roof.

But ABS canoes are more expensive than aluminum and are vulnerable to wear and tear at bow and stern, making optional skid- plates desirable for boats that are likely to spend much time in harm's way.

The market also offers canoes made of polyethelene plastic or Kevlar; wood and wood-and-canvas boats still are made but are seldom seen around here.

Springriver sells very few fiberglass canoes except for special and limited purposes, Reardon said. "I have a little 13-foot Mansfield canoe here that is very stable and very quiet. It is a favorite of fly fishermen and marshland hunters."

Like all good fiberglass canoes, it costs upwards of $500. Good fiberglass boats are handmade, layer by layer. Cheaper fiberglass canoes, made of chopped cloth blown into molds, are a waste of money.

Aluminum Grummans are beginning to make a comeback because the prices have not gone up in recent years, while makers of plastic hulls, whose raw material is petroleum, have been at the mercy of OPEC. The top-grade aluminum canoes are made of 6061 T-4 alloy.

Both Reardon and Bob Lichtenberg of Hudson Bay Outfitters feel that the Coleman brand polyethelene plastic canoes are good starter boats. If you are willing to spend a few hours assembling it you can get a Coleman canoe kit for $330 to $390. Hudson Bay will put one together for an extra $30. Grumman's new polyethelene Eagle is designed to compete with the Colemans.

Although the superlight Kevlar boats are very popular in areas where long portages are common, they don't sell well in Washington. Kevlar is a rein-saturated cloth, similar to fiberglass but lighter, tougher and more expensive. Most local canoeists and retailers have yet to be convinced that it will stand up to our rocky rivers, although Appalachian Outfitters promotes the Sawyer Kevlar canoe as suitable for whitewater. Time will tell.

The big sellers in this area are the 16- and 17-foot models of the Old Town and Blue Hole ABS canoes, although ABS Mad Rivers and Mohawks are coming on strong. Prices run upwards of $700.

Length is not a major price factor: the difference between the 15- and 17-foot Colemans is about $50. A solo paddler can do well with a 12- or 13-foot boat, but 15 feet is about the minimum for two people. Most tandem canoes are 17-footers.

The shape of the bottom determines a canoe's stability, straight-ahead tracking and speed; they range from deep-V to flat.

All aluminum canoes have some kind of keel because it is necessary in the manufacturing, but "In today's canoes, keel is not as important as the shape of the hull," Lichtenburg said. "A canoe with a V hull will track straight and steady without any keel."

The keel line, which is different from keel, is the shape of the bottom as seen from the side. It can be straight or curved up on the ends like a rocker; the more curve, the quicker it turns but the harder it is to hold to a straight line.

Many buyers plan to add motors. "A 17- foot canoe can accomodate about a five- horsepower motor," Reardon said. "We sell a lot of motor mounts to people who want the option of using power on lakes and long flatwater stretches." He suggests that anyone who plans to use a motor more than half the time buy a square-stern canoe. Both Old Town and Grumman also offer sailing rigs.

Springriver carries Grumman, Old Town, Blue Hole and Coleman canoes, among others. Hudson Bay has Colemans, Michicraft and Mad River. Clark Brothers in Warrenton carries all these plus Mohawks.

All U.S. canoes and some from Canada were described in the December 1981 issue of Canoe Magazine. Copies may be available at canoe shops or for $2 from Canoe, Highland Mill, Camden, Maine 04834.

If you're not sure what boat you want or where you'll be using it, don't buy until you have tried several; you can rent them at local liveries. Ask experienced paddlers which ones they like and why. They love to talk about canoes and even lend them out.