58 PLANT LIFE IN OKLAHOMA. 



A LIST OF TREES AND SHRUBS OF OKLHAMOA. 



Trees and shrubs are plants which belong to the sub-kingdom. — 

 SPERMATOPHYTA— the seed-bearing plants. The plants of this di- 

 vision belong to two classes — the GYMNOSPERMAE, plants with naked 

 seed; and ANGIOSPERMAE, plants with protected seeds. 



CLASS I. GYMNOSPERMAE. 

 Naked Seeds. 

 The Gymnosperms are an ancient group of plants. They are found 

 among the fossils of the Silurian age, and are most numerous in Triassic 

 time. They are now represented by about 450 species of trees and shrubs. 

 They are flowering plants in which the ovules, or seed?, are not inclosed 

 in an ovary, but are borne naked upon an open scale. This scale is a 

 modified leaf. The plants have a resinous juice, and chiefly parallel- 

 veined, needle-shaped, or scale-like evergreen leaves. By far the larger 

 number of the Gymnosperms are Coniferous (Pinacae or Coniferae in- 

 cluding some shrubs) or cone-bearing trees, the fruit being called a cone 

 ■because of its form. This family of the class is the only one represented 

 in our area. 



PINE FAMILY. PINACEAE. 



Pines. Conifers. 

 Pinaceae. Coniferae. 

 The trees belonging to this family are commonly known as Ever- 

 greens, because with the exception of the Larch and the Bald Cypress 

 they do not shed their leaves during the winter. 



PINES. GENUS PINUS. 



Loblolly pine. (Old Field pine. Rosemary pine). 



Pirms Taedea. 



Yellow pine. (Short-leaf pine. North Carolina pine, Spruce pine.) 



Pinus echinata. 



Southern or Bald cypress. (Deciduous cypress.) 



Taxodkmi distKhum. 



Red cedar. (Common cedar. Juniper.) Juniper. (Ground cedar.) 



Juniperus Virginiand. Junipems communis. 



Arbor vitae. (White cedar.) 



Thuja occidientalis. 



CLASS II. ANGIOSPERMAE. 

 Enclosed Seeds. 



MAGNOLIA FAMILY. MAGNOLIACEAE. 

 Found in the extreme eastern and southeastern part of the State. 



TULIP TREE. GENUS LIRIODENDRON. 



Tulip tree. (Yellow poplar. Tulip poplar.) 

 Liriodend/ron tulipifera. 



