The Plants of Michigan Part 23

THE PLANTS OF MICHIGAN

PINACEAE, the Pine Family

Trees or shrubs, usually evergreen, with needle-like or scale-like leaves; fruit a cone or berry.

1a. Leaves in cl.u.s.ters of 2-5 --2.

1b. Leaves mostly in cl.u.s.ters of 10 or more, on short lateral wart-like branches, deciduous each autumn =Tamarack, Larix laricina.=

 

1c. Leaves not in cl.u.s.ters --4.

2a. Leaves in cl.u.s.ters of 5 =White Pine, Pinus strobus.=

2b. Leaves in cl.u.s.ters of 2 or 3 --3.

3a. Leaves 8-15 cm. long =Norway Pine, Pinus resinosa.=

3b. Leaves 2-4 cm. long =Jack Pine, Pinus banksiana.=

4a. Leaves alternate or scattered --5.

4b. Leaves opposite or whorled --8.

5a. Leaves four-sided --6.

5b. Leaves flattened --7.

6a. Leaves 6-12 mm. long =Black Spruce, Picea mariana.=

6b. Leaves 15-25 mm. long =White Spruce, Picea canadensis.=

7a. Leaves short-stalked, 15 mm. long or less =Hemlock, Tsuga canadensis.=

7b. Leaves sessile, 15-30 mm. long =Balsam, Abies balsamea.=

8a. Leafy twigs soft and flattened =White Cedar, Thuja occidentalis.=

8b. Leafy twigs not distinctly flattened --9.

9a. Leaves opposite --10.

9b. Leaves in whorls of three --11.

10a. Erect shrub or tree =Red Cedar, Juniperus virginiana.=

10b. Prostrate or spreading shrub =Creeping Cedar, Juniperus horizontalis.=

11a. Erect shrub or small tree =Juniper, Juniperus communis.=

11b. Spreading or ascending shrub, growing in dense mats =Low Juniper, Juniperus communis var. depressa.=

TAXACEAE, the Yew Family

Shrubs, with needle-like evergreen leaves; fruit red and berry-like.

One species in Michigan; straggling shrub 1-3 m. high =Ground Hemlock, Taxus canadensis.=

TYPHACEAE, the Cat-tail Family

Erect plants 1-2 m. high, with linear leaves and terminal spikes of brown flowers, appearing in summer.

1a. Staminate and pistillate portions of the flower-spike contiguous, the latter 2.5 cm. in diameter =Common Cat-tail, Typha latifolia.=

1b. Staminate and pistillate portions of the spike separated, the latter 2 cm. or less in diameter =Narrow-leaved Cat-tail, Typha angustifolia.=

SPARGANIACEAE, the Bur-reed Family

Marsh plants with linear leaves and spherical heads of inconspicuous greenish flowers, appearing in summer.

About 5 species occur in Michigan, of which the commonest is =Bur-reed, Sparganium eurycarpum.=

NAJADACEAE, the Pondweed Family

Aquatic plants with submerged or floating leaves and inconspicuous flowers in summer.

1a. Leaves opposite or whorled --2.

1b. Leaves alternate --2c.