656 JOURNAL OF FORESTRY 



should be made separate species. The blue Douglas fir, which Tubeuf 

 suggests be called Pscudotsuga glauca, occurs especially in the more 

 arid portions of New Mexico, Arizona, Colorado, and northward to 

 Montana and British Columbia. The green Douglas fir, which Tubeuf 

 suggests be called Pseudotsuga donglasii, occurs especially in the 

 moister regions from the island of Vancouver, in British Columbia, 

 southward through the Cascades and Sierra Nevada, as well as along 

 the Coast. 



The blue, he claims, is a mountain variety ; the green a lowland 

 variety. The former is pyramidal in shape ; the latter broad-crowned. 

 The blue is slow growing and frost-hardy ; the green is ®f rapid growth 

 but susceptible to frost. 



This form of species-mongering is to be strongly deprecated. It has 

 been carried ad nauseam by Sargent in the case of Crataegus and 

 others of less prominence have followed suit, until confusion in the 

 field of dendrology has become worse confounded. As Wiebecke once 

 said : "The botanists also have names for this tree." No, there is only 

 one Douglas fir and its scientific name (0/ patientia nostra) is Pseu- 

 dotsuga taxifolia. If we change it at all, let us call it Douglana 

 americana or some such sensible name. 



Tempted by the blue and the green Douglas fir, Tubeuf next ad- 

 dresses himself to proving (to his own if not to our satisfaction) that 

 the variety of western yellow pine, which occurs in the foothills of the 

 eastern and the southern Rockies, is a separate species— Piiius scopu- 

 lorum. This merits the same criticism as the attempt to differentiate 

 two species of Douglas fir. 



Much of what follows is a description of different kinds of mistletoe 

 on western conifers. On this subject Tubeuf is an acknowledged 

 authority. 



Tubeuf makes this interesting observation : "It struck me that in 

 the hot and arid regions, very many of the woody plants have a smooth, 

 white, light-reflecting bark, and that in such regions the blue-white 

 color of the needles of conifers is very marked. Such bark and 

 needles decrease the heat-absorption and, in the case of the needles, 

 also decreases the evaporation, in opposition to the effect of the sun, 

 which always produces strong heating and strong evaporation at the 

 same time." 



Tubeuf speaks a good word for the Fremont Experiment Station, 

 which he visited. 



