Under the North Star, by Ted Hughes. New York: The Viking Press. 46 pp. $ 14.95.

This stunningly illustrated book of poems offers an armchair journey into the wildest reaches of the north woods. Moose, wolves, bears, and even the lowly mosquito are among its subjects. Described with vivid and sometimes harsh imagery and appropriate sounds, the animals almost leave the printed page and take on shapes of their own.

It's difficult to read ''The Black Bear,'' for instance, without conjuring up the vision of a great somber beast lumbering its way through the wild. ''The Bear's black bulk/ Is solid sulk,'' Hughes writes. ''He mopes with his nose/Between his toes.''

There is more than a touch of awe in these poems that celebrate even the cruelest or most laughable aspects of the natural world. Often complex subjects are treated with an unflinching eye, and older children will enjoy the poetry more than the very young.

Leonard Baskin's handsomely colored drawings are a fine complement.