1	"Leaves in a flattened 2-ranked or feather-spray arrangement"	2
1	"Leaves not 2-ranked or in feather sprays, spirally arranged or closely pressed to stem"	4
2	"Leaves stiff and more than 3 cm long, gradually tapering to a point"	Cunninghamia
2	"Leaves flexible, not spiny and less than 3 cm long"	3
3	"Leaf sprays alternate, individual leaves c. 1 mm wide"	Taxodium
3	"Leaf sprays opposite, individual leaves more than 1 mm wide"	Metasequoia
4	"Leaves more than 1 cm long, rigid, strongly ridged on the back"	5
4	"Leaves less than 1 cm long, if greater then curved and rounded on the back"	6
5	"Leaves dark blue-green; male cones clustered; female cone scales rounded, 2 seeds per scale (rarely cultivated)"	Taiwania
5	"Leaves dark green; male cones solitary; female cones with toothed scales each with 3 seeds"	Cryptomeria
6	"Leaves scale-like, incurved; mature cones ovoid, spiny (rare in cultivation)"	Athrotaxis
6	"Leaves short, spreading, more or less linear; mature cones ellipsoid, smooth"	Sequoiadendron