Dichotomous Key/Pinales

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The order Pinales is composed of

Incertae sedis

1: Trees produce cones or arils.

2: Leaves alternate or in fascicles or clusters (not opposite or whorled), needle-like,
(scale-like leaves often present on fruiting branches of Taxodium); fruit a cone.
3: Leaves in fascicles of 2-5 leaves or mostly in clusters of many leaves on
spur-like branches.
4: Leaves in fascicles of 2-5 leaves, persistent.........................Pinus
4: Leaves mostly in clusters of many leaves on the ends of spur-like branches,
deciduous............................................................................Larix
3: Leaves scattered, alternate.
5: Ultimate twigs very slender, greenish and mostly deciduous; leaves deciduous, yellowish-green,
much flattened and in two ranks; bark fibrous; cones with several wedge-shaped
woody scales......................................................................Taxodium
5: Ultimate twigs not deciduous; leaves persistent, not yellowish-green above;
bark not fibrous.
6: Branchlets roughened by the persistent leaf bases; leaves deciduous when dry; cones pendulous, the bracts shorter than the cone scales.
7: Leaves sessile, mostly four-sided, often sharp-pointed................Picea
7: Leaves stalked, flattened, blunt......................................Tsuga
6: Branchlets not roughened by persistent leaf bases.
8: Leaves sessile, flattened, (seldom four-sided); leaf-scars orbicular, not decurrent;
cones erect, the scales deciduous.......................................Abies
8: Leaves stalked, flattened; leaf-scars decurrent.
9: Leaves mostly with obtuse tips and with two white lines on the lower surface;
cones pendulous, the scales persistent in the axils of long exserted bracts.........Pseudotsuga
9: Leaves with acute tips, yellow-green on the lower surface; "fruit" drupe-like........Taxus
2: Leaves opposite or whorled, often of two kinds, scale-like, awl-shaped, or linear.