The family PINACEAE
This most important family, which is by far the largest in number of species, consists mainly of trees, all native in the Northern Hemisphere. The branched are characteristically whorled. The leaves are linear, spirally arranged and usually evergreen (but Larix and Pseudolarix deciduous). The strobili (cones) are unisexual: the plants monoecious. The scales of the staminate strobilus have two or more pollen sacs on the lower surface and the pollen grains are usually winged. The ovulate strobilus consists of two distinct kinds of scales spirally arranged, the ovuliferous scales, each bearing two ovules on its upper surface, and the smaller bract scales. The ripe cones are woody and the seeds are winged.
Pinaceae includes the genera:
Pinus