TREES OF MINNESOTA. 



CONIFERA.E. Fine Family. 



Trees or shrubs with resinous juice. Leaves commonly 

 needle-shaped or awl-shaped and mostly evergreen. Flowers 

 monoecious or sometimes dioecious, in catkins or cones, des- 

 titute of calyx and corolla. The pollen grains have lateral 

 air sacs which buoy them up in the air and they are occasion- 

 ally carried hundreds of miles by the wind. Fruit either a 

 woody cone with distinct scales as in the pines, spruces, 

 Arborvitae and Larch or a somewhat berry-like cone with 

 fleshy coherent scales as in the Red Cedar. 



Genus PINTTS. 



Leaves of two kinds; the primary ones, linear or scale 

 like, deciduous; the secondary forming the ordinary foliage 

 evergreen, from slender buds, in clusters of 2, 3 or 5 together, 

 each cluster surrounded by a sheath of thin membranous 

 scales. Flowers appear in the spring, monoecious; the 

 staminate in scaly catkins clustered at the base of the new 

 growth; the pistillate in scaly catkins borne on the twigs of 

 the preceding season becoming scaly cones at maturity. Each 

 scale is in the axil of a bract and bears a pair of ovules ad- 

 hering to its inner face wLich peel off as the scale expands at 

 maturity. Fruit a woody cone maturing in the autumn of the 

 second year. Cotyledons 3 to 12, linear. We have only 

 three native species in this state. 



Pinus strobus. White Pine. Weymouth Pine. 



. Leaves soft, in clusters of 5, about 3 to 4 inches long, 

 falling at the end of the second or during the third season ; 

 sheath early deciduous. Sterile catkins 5 or 6 together. 



