If you want to catch trout 12 months of the year, all you need are a handful of dry flies and nymphs.

In southern Appalachian trout streams, various mayfly, caddis and stone hatches occur from January through December. Granted, the hatches are sparser and less frequent in the winter and summer, but trout have to eat no matter what the weather conditions are.

One of the most consistent hatches, especially in the Great Smoky Mountains National Park and surrounding streams, is the Blue-Winged Olive, a Mayfly in the same company as a Hendrickson, Sulphur, Red Quill and Pale Morning Dun.

All it takes is a little sun to activate Blue-Wings. Other year-round flies include the Elk-Hair Caddis (tan or yellow) and the stone flies, particularly the Yellow Stone.

A Woolly Booger also is an effective year-round pattern. Darker colors such as brown, black and gray work best in the colder months, and lighter patterns work well in the spring, summer and fall.

For winter fishing, carry a thermometer to check changes in water temperature. Trout are more active when the water temperature is at least 40 degrees. In the summer, choose heavily-shaded pools and runs and areas where small tributaries enter the stream.

Here's a month-by-month guide for selecting flies:

• January-Februay - As far as weather goes, these are the two roughest months of the year, a time when we get the most cold weather, snow and ice.

Trout don't move around much, nor do they feed often, especially when temperatures are at the freezing or below freezing level. Look for trout in deep pools and get nymphs down deep by adding extra weight and bump them along the bottom.

Good patterns for top water are No. 16 Dark Caddis, No. 14 Black Stone, No. 16 Blue-Winged Olive, No. 20-18 olive Midge, No. 16-14 male Adams and No. 14-12 Quill Gordon. For nymph fishing, go with a No. 10 Dark Stone, No. 10 My Pet, No. 14-12 Pheasant Tail, No. 14-10 Hare's Ear and No. 12-10 Prince.

• March - For the past few years, we've had nasty weather more typical of January and February than early spring.

Most of the flies used during January and February are still effective. Toward the end of the month, March Browns and Hendricksons begin hatching, both good patterns.

Suggested sizes are No. 14 and 16. Recommended nymph patterns are No. 10 Peeking Caddis, No. 8 Brown Stone, No. 10 Tellico, No. 10 Secret Weapon and No. 10 olive Stone.

• April-May - I've known a few trout fishers who say the only months worth fishing are April and May.

This is the time when the widest arrays of hatches come off, and trout are gorging to make up for the lean winter months.

Primary hatch patterns include No. 14 Red Quill, No. 18 Blue Quill, No. 14 Hendrickson, No. 16-14 Light Caddis, No. 16-12 Light Cahill, No. 16-14 Sulphur Dun, No. 12-10 Yellow Mayfly, No. 16-14 female Adams and No. 14 green or yellow Elk Hair Caddis. Good nymph patterns are No. 10-8 Yellow Stone, No. 10 Tellico, No. 10 Stick Bait, and No. 10-8 Yellowhammer.

In late May, watch for Green Drake hatches. Best time to fish Green Drakes is at dusk. These are large insects, so you'll need a No. 8 or 10.

• June - A lot of stone, caddis and Mayfly hatches occur during June.

In the dry-fly category, best bets are No. 16-14 little Yellow Stone, No. 16-14 Little Green Stone, No. 18-16 Light Cahill, No. 22-14 Light Quill and No. 14-12 Pink Lady.

June is typically the time to start using a variety of terrestrial patterns such as No. 10 Inchworm, No. 12-10 Beetle, No. 12 black Ant, No. 8 Hopper, No. 10 Caterpillar and No. 10 Cricket.

• July-August - Fishing generally slows down this time of the year, and trout become more selective.

Best dry-fly fishing occurs during early morning and late evening.

Nymphs work best fished deep during the middle of the day.

Suggested dry-fly patterns are No. 20-18 crème or yellow Midge, No. 10 Giant Yellow Mayfly, No. 10 Black Quill and No. 12 Adams.

In addition to terrestrial patterns, recommended nymph patterns are No. 10-8 Brown Stone, No. 10 Cahill, No. 10 Secret Weapon, No. 10 Sheep Fly, and No. 12-10 Pheasant Tail.

• September - Usually the mountains get cooler weather in September, at least at night. As a result, trout are active and hungry.

This is a good time to fish for big browns and rainbows using large terrestrials and streamers.

For top-water fishing, try No. 20-16 black and white Trico, No. 16 small white Mayfly. For nymph fishing, good bets are No. 10-8 Brown Stone, No. 8 Hellgrammite and No. 10 Yellow Jacket.

• October-November - This is the time to watch for spawning brown trout. Tributaries are prime spots fish during the fall spawn.

Use large flies such as a No. 12-10 chartreuse, olive or black Woolly Booger, a No. 10 Bitch Creek or a No. 21-10 Girdle Bug. Ideal spawning conditions are when water temperatures are between 44 and 48 degrees, and spawning can start as early as September and continue through November, since not all browns spawn at the same time.

Suggested dry-flies for October and November are No. 20-18 Blue-Winged Olive, No. 16-14 Royal Wullf, No. 16-14 Orange Palmer, No. 16-14 Red Humpy, No. 16-14 Stimulator and No. 61-14 Autumn Dun.

Effective nymph patterns include the No. 10 Secret Weapon, No. 10 Shell Back, No. 12-8 Muddler Minnow and No. 10-8 Streamer.

• December - Although hatches are common during December, nymph patterns usually are preferred.

Suggested nymph patterns are No. 10 My Pet, No. 10 Mink Hair, No. 12-10 Zug Bug, No. 8 Woolly Booger, No. 10 Girdle Bug, No. 12-10 Prince, and No. 10-8 Brown Stone. Best time to fish in the winter is the middle of the day.

You certainly won't need all the suggested patterns. Pick a few key patterns for each month, and you're pretty well guaranteed to catch trout January through December.