Crossword puzzle clue "central veins of leaves"

COSTA, (Latin) a rib

AREOLA, (Latin) a small space in a network of leaf veins, also AREOLE

MIDRIB, the central vein of a leaf

DEFOLIATE, to remove the leaves from

to gather with a toothed bar on a handle

RAKE, to gather with a toothed bar on a handle

the mixture of gases breathed by people and animals, also AYRE