16 WOODY PLANTS 



KEY TO THE GENERA OF WOODY PLANTS 



1. Foliage evergreen. 2 



1. Foliage deciduous. 31 



FOLIAGE EVERGREEN 



2. Small yellowish-green parasites on trees. . . Phoradendron, p. 89 



2. Not as above. 3 



3. Leaves 8 mm. or less in width. 4 



3. Leaves 12 mm. or more in width. 15 



4. Leaves in fascicles of 2, 3, or 5. , . Pinus , p. 35 



4, Leaves not in fascicles. 5 



5. Leaves alternate, in spirals, linear. 6 



5. Leaves opposite, awl-shaped or scale-like. 13 



6. Leaves 3 - or 4 - angled in cross section. . . Picea, p. 33 



6. Leaves flattened. 7 



7. Stems trailing or creeping. 8 



7. Stems erect. 9 



8. Stems chaffy; leaves green on both sides. . . Gaultheria, p. 173 



8. Stems not chaffy; leaves whitened beneath. , . Vaccinium , p. 175 



9. Low sprawling shrubs. 10 



9. Trees. 12 



10. Leaves white-hairy. . . Hudsonia, p. 154 



10. Leaves glabrous. 11 



11. Leaves alternate; shrubs to 1 m. high. . . Taxus, p. 31 



11. Leaves opposite; usually less than 25 cm. high. , . Pachistima, p. 137 



12. Leaves sessile. . .Abies, p. 31 



12. Leaves jointed to short persistent sterigmata. . .Tsuga, p. 31 



13. Sprays not flattened. 14 



13. Sprays flattened. . . Thuja, p. 41 



14. Leaves opposite, scale-like. . . Chamaecyparis. p. 43 

 14. Leaves dimorphic, ternate on young growth, 



opposite on older branches. . . Juniperus, p. 43 



