VIL TREE RECORDS: GEOGRAPHICAL DISTRIBUTION 



The understanding of any special distribution of ring characters 

 over great areas is increased by personal acquaintance with the region. 

 So, in addition to much travel in the Southwest, both within and with- 

 out the State of Arizona, the writer has made two special trips in the 

 study of geographical distribution of tree-growth. 



WESTERN CIRCUIT, 1925 



This trip was made easterly from Tucson to the Rio Grande Valley, 

 thence up-stream to Albuquerque and east again to Santa Fe, where 

 the SF group had been collected in 1922; thence through the pine- 

 covered mountains to Las Vegas. Halfway between these cities we 

 passed Pecos, where the "L" group of four trees had been obtained, by 

 aid of the Forest Ranger. However, only one of these proved suitable 

 for dating, and so this is not retained as a group. The next day car- 

 ried us over the wide elevated plains of northeastern New Mexico to 

 Raton, whose mountain pass through the Rockies is high enough to be 

 pine-covered. Three of the trees near the road were bored, but only one 

 could be dated reliably, and as we already had a group from Cloudcroft, 

 New Mexico (CC group), this single tree is omitted. Later we went 

 along the eastern base of the mountains to Fort Collins, Colorado, 

 and Laramie, Wyoming. In the low hills between these two places, 

 the group LW (Laramie, Wyoming) was collected near the road. 



The eastern face of the Rocky Mountains, extending north and 

 south for many hundreds of miles, is a striking feature of western 

 contours, and the groups in New Mexico, Colorado, and Wyoming 

 along this line and partly also the small Yellowstone group from 

 Specimen Ridge in the northeast corner of the park (collected in 1920) 

 give certain interesting characters which will be referred to later. 



The next stop for collecting was 60 miles northwest of Baker, 

 Oregon. At a point where pine trees border the road as it passes over 

 the Blue Mountains, the BO (Baker, Oregon) group of 8 was collected. 

 On the eastern slopes of the hills near the road at The Dalles are more 

 yellow pines, of which a small collection was made, known here as the 

 DL (Dalles) group. In the low coast hills 25 miles northwest of Port- 

 land, a large group of Douglas firs was collected in 1912, as described 

 in Volume I. It now appears that this group, called OC (Oregon 

 Coast), does not cross-identify with the other western groups, probably 

 because its location close to the coast gives a very different climatic 

 environment. 



The primeval forests of the State of Washington were extensively 

 cut along the settlement-line marked by the highway between Port- 

 land and Seattle. Much of the land was burnt over and the huge 



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