Cupressaceae
Monoecious or dioecious, evergreen trees or shrubs; leaves in opposite pairs in whorls of 3, scale-like or lance-like, mature female cones leathery, or woody, or berry-like of fused scales.
Monoecious tree; mature female cone leathery or woody.
Cones globose, the scales not overlapping....................................................Chamaecyparis
Cones cylindric, the scales overlapping...........................................................................Thuja
Dioecious tree or shrub; mature female cone berry-like, of fused scales.................Juneriperus
CHAMAECYPARIS
THUJA
JUNERIPERUS
Shrub; leaves in whorls of 3, flattened, subulate with upturned edges, a white line on upper surface; berry-like female cones 6-10 mm in diameter maturing second year................................................................................J. communis
Tree; leaves short scales in close-set, alternating, overlapping pairs, forming 4-sided twigs, except in juveniles, where leaves are longer, flat, pointed, more distant, and in whorls of 3; berry-like cones less than 6 mm in diameter and maturing first year.
Female cones 5-6 mm long; male cones 3-4 mm long............................................J. virginiana
Female cones 3-4 mm long; male cones 5-6 mm long............................................J. silicicola
Monoecious tree; mature female cone leathery or woody.
Cones globose, the scales not overlapping....................................................Chamaecyparis
Cones cylindric, the scales overlapping...........................................................................Thuja
Dioecious tree or shrub; mature female cone berry-like, of fused scales.................Juneriperus
CHAMAECYPARIS
THUJA
JUNERIPERUS
Shrub; leaves in whorls of 3, flattened, subulate with upturned edges, a white line on upper surface; berry-like female cones 6-10 mm in diameter maturing second year................................................................................J. communis
Tree; leaves short scales in close-set, alternating, overlapping pairs, forming 4-sided twigs, except in juveniles, where leaves are longer, flat, pointed, more distant, and in whorls of 3; berry-like cones less than 6 mm in diameter and maturing first year.
Female cones 5-6 mm long; male cones 3-4 mm long............................................J. virginiana
Female cones 3-4 mm long; male cones 5-6 mm long............................................J. silicicola