Woods commonly used in barbecues:
Alder: A fine hardwood for smoking and barbecuing. Alder has a distinct but mild flavor. It is difficult to use too much alder. This wood is excellent for smoking or barbecuing trout, salmon, albacore, and whitefish. It is also good for beef and fowl, but may be hardly noticeable with the stronger flavored meats. Alder is a subtle smoke flavor compatible with all meats, fish and fowl.
Apple: A few dried apple twigs or trimmings make a good addition to the smoke of a fire. The flavor that apple imparts to the food is moderate in intensity. A large amount is not necessary and the flavor is pleasant.
Corncobs: Corncobs are obviously not wood, but are included here because the corncob's smoke flavor is very unique, and imparts an almost sweet taste to the food. I've heard that the corncob smoke flavor is one of the secrets to the famous Virginia smoked ham. I save the cobs from the summer sweet corn to use for smoke when cooking pork spareribs, steak, and warm smoked trout and salmon. It makes superb smoke flavoring addition for all foods.
Hickory: Many unseasoned barbecue cooks use hickory to an extreme. The flavor of hickory is very strong as woods go. Too much hickory imparts a bitter flavor to the food which may be offensive to some people. Use hickory sparingly. It is an excellent wood for cooking steaks over a hot open fire, and is very good with pork. Use sparingly for salmon, trout, and other fish. Moderation is the key to successful flavoring with hickory.
Manzanita: This wood burns very hot and relatively fast. It is rare unless you happen to live in the right area. This wood should be used like sycamore, but keep in mind that it burns much hotter. This wood is great for open fire cooking or as a basis for coals used in smoking.
Mesquite: Mesquite has a very subtle flavor suitable for most types of outdoor cooking. It generally is used in flavoring commercial charcoal, but the flavored charcoal is no substitute for the real thing. Mesquite is a versatile wood suitable for barbecuing meats or for smoking fish when used in moderate quantity.
Oak: Oak is one of the finest woods for cooking because it burns long and hot. It also has one of the finest flavors for beef, fish, and fowl. Oak flavor is mild, so it is difficult to use too much. It is an excellent wood to use as the basis of a barbecue, adding flavors from other wood to the oak before cooking.
Sycamore: Sycamore burns fast and relatively hot. It is therefore best suited for cooking hamburgers, steaks, shish kabob, short ribs of beef, and other foods which require a hot fire and cook fast. The flavor of this wood is not particularly interesting. It is good for grilling but not for smoking.