( \ PRESS AND JUNIPER TREES OF ROCKY MOUNTAIN REGION. 3 



Naturally the ranges of the better known and more useful trees 

 are more complete than those of the smaller, relatively unimportant 

 ones. Altogether, however, our present knowledge of the geographic, 

 distribution of Rocky Mountain cypresses and junipers is still incom- 

 plete. It is hoped, therefore, that the publication of range data now 

 available will stimulate the collection of further information. 



A key for the identification of junipers is provided on page 36. 

 One for the cypresses is deemed unnecessary, because the two species 

 considered are so strikingly different that they can be quickly identi- 

 fied by consulting the descriptions. 



In this connection the writer wishes to say that trees, as is the 

 case with other plants, can be satisfactorily identified only by first 

 becoming familiar with the character and appearance of their foliage, 

 flowers, fruits, bark of the trunk and branches, wood, and habit of 

 growth. Knowledge also of their natural habitat and associates is 

 helpful and an essential part of the life history. Naturally such 

 information can be obtained best by studying trees where they grow. 

 Representative specimens of the different parts of the tree are useful 

 for further study, and should be collected whenever possible. Merely 

 a few sprigs hastily taken in passing a tree will not be a sufficient 

 means of determining and knowing the species. 



CLASS AND FAMILY RELATIONSHIP OF CYPRESSES AND JUNIPERS. 



The cypresses and junipers belong to a class of plants technically 

 known as Gymnosperms, which are distinguished by their resinous 

 wood and in the fact that their ovules (destined to become seeds) 

 are borne naked or without the usual covering peculiar to the other 

 great class of seed-bearing trees called Angiosperms. Familiar 

 examples of the Gymnosperms are the pines, spruces, firs, etc., while 

 the Angiosperms include the oaks, walnuts, hickories, etc., which 

 do not have resinous wood. Gymnosperms produce wood which is 

 formed in concentric layers or rings of growth, one ring being laid 

 on each year and outside of the preceding one and just beneath the 

 bark. The age of Gymnosperms can, therefore, be accurately told 

 by counting the rings shown on a cross section of the stem cut off 

 at the ground just above where the root is given off. 



According to the character of their fruits, Gymnosperms are divided 

 into two families — (1) Coniferse, trees which bear cone fruits (pines, 

 etc.), and (2) Taxacese, trees which bear an olivelike fruit (the seed 

 inclosed in a fleshy sack), as in the yew trees. 



Because their fruits are true cones, cypress and juniper trees belong 

 to the family Conif erse. Other generic groups of this family are the 

 pines (Pinus), spruces (Picea), larches or true tamaracks (Larix), 

 hemlocks (Tsuga), false or bastard hemlocks (Pseudotsuga), firs or 



