THE PLANTS OF MICHIGAN Division PINOPHYTAâ€”The Gymnosperms

THE PLANTS OF MICHIGAN Division PINOPHYTA—The Gymnosperms TAXACEAE, The Yew Family Dioecious evergreen shrubs, with spirally arranged, linear leaves. Male cones small; seeds solitary, on axillary branches and covered with fleshy red tissue, resembling a berry. One species in Michigan, a low shrub with ascending branches (to 2 m high)—Ground-hemlock, Taxus canadensis PINACEAE, The Pine Family Monoecious trees, usually evergreen, with needle-like leaves either spirally arranged (appearing to be alternate) or in clusters (fascicles). Male cones small, not woody; female cones larger and often woody, the seeds in pairs on spirally arranged scales. 1a. Leaves grouped in fascicles—2 1b. Leaves alternate, not in fascicles—5 2a. Leaves mostly in fascicles of ten or more, on short lateral wart-like branches, deciduous each autumn; often in bogs (to 20 m high)—Tama- rack, Larix laricina 2b. Leaves in fascicles of two or five (Pinus spp., Pine)—3 3a. Leaves in fascicles of five (to 70 m high)—White Pine, Pinus strobus 3b. Leaves in fascicles of two—4 93 Pinus strobus, the white pine, is the Michigan state tree. At one time significant areas of the Upper Peninsula and the northern Lower Peninsula were covered with immense specimens (150–200 feet high) of this species. From 1870–1890 Michigan led the nation in lumber production, much of which was white pine. Most had been logged by the early 1900s, at which time the fungus Cronartium ribicola, the causal agent of white pine blister rust, was introduced from Europe. Although white pine was subsequently planted on state lands, this disease made production of lumber-quality trees infeasible. A remnant of the original majestic forest survives in Hartwick Pines State Park, near Grayling. 4a. Leaves 8–15 cm long (to 40 m high)—Red Pine, Pinus resinosa 4b. Leaves 2–4 cm long (to 20 m high)—Jack Pine, Pinus banksiana

THE PLANTS OF MICHIGAN Division PINOPHYTAâ€”The Gymnosperms

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