A walker on a woodland trail notices a lost black glove stuck to an oak, and that small odd sight seems to open his eyes. Suddenly the trees have faces: pot-bellied maples, big oaks with limbs thrown wide. The speaker works out what they are. They were left standing in an old pasture to shade the cattle, and now the field around them is filling in with young timber and a haze of baby white pines.
The mood is quiet, curious, and a little humorous. There's no sadness about the farm disappearing; the speaker seems more amused and fascinated by how the land takes itself back. The final image is the best part. The pasture climbs "toward the bovine clouds," as if the grazing animals have drifted off into the sky. The title, "Cow Heaven," fits that idea: the cattle are gone, but the place still feels shaped by them, and the forest slowly rises into something like their afterlife.