NOTES ON THE PLANT DISTRIBUTION OF MT. 

 WASHINGTON, N.H. 



By John I. and Alice R. Northrop 



In the course of a week's botanizing on the summit of Mt. Washing- 

 ton in the early summer of 1889 (July 2-9), a fairly complete collec- 

 tion of its flora was made, largely with the view of ascertaining the 

 distribution of the plants in relation to altitude. The respective 

 elevations were determined by means of an aneroid barometer. The 

 following pages give a brief resume of the results obtained. 



The base of the mountain, where the cog railway begins, was made 

 out to be approximately 2500 feet. Here the flora was about the 

 same as in the valley. During the first five hundred feet of elevation the 

 mountain ash (Pyrus sitchensis (Roem.) Piper), Acer spicatum Lam., 

 Acer pennsylvanicum L., Prunus pennsylvanica L. f., Picea mariana 

 (Mill.) B. S. P., and Ahies halsamea (L.) Mill, were noted. Of these 

 the striped maple {Acer pennsylvanicum) was not seen above 3000 feet 

 of elevation, Betula lutea Mich, f., and Acer spicatum were infrequent 

 in the second five hundred feet and did not reach the 3500 limit, while 

 Prunus pennsylvanica w3iS abundant up to 3500, but was entirely want- 

 ing above 4000 feet altitude. Pyrus sitchensis, at first very plentiful, 

 was much less common at 4000 feet, and at 4300 feet was noted only 

 as a straggling bush. A single specimen was found at an altitude of 

 5700 feet near the trail leading into Tuckerman's Ravine. Betula 

 alba L., var. papyri/era, was abundant from 3500 to 4000 feet, but was 

 much less frequently met with beyond the 4300 limit, and higher up was 

 replaced by the variety minor (Tuckerm.) Fernald. This, as a low 

 straggling bush, held its own far above the timber line, while about 

 the summit it in turn gave way to Betula glandulosa Michx. 



The two conifers, Picea mariana and Abies balsamea, were con- 

 spicuous throughout, and from 4300 feet upward were almost the only 

 woody plants to be found. They grew as stunted shrubs, two or 

 three feet in height, at an altitude of 5000 feet, and even above that a 

 s 255 



