398 BOTANICAL GAZETTE [November 



Hartig then obtained results comparable to the present ones; 

 that is, at about the middle of June he observed that growth was 

 most advanced near the middle of the tree and decreased in both 

 directions from that point. And yet he persists in his assertion 

 that growth ceases in trees in open stand first in the youngest 

 branches. Such being the case, the only possible solution of the 

 data given above is that there must have been a marked accelera- 

 tion of growth in the apical portions after June 21 and a corre- 

 sponding decrease in the parts below. Whether the same applies 

 in the pitch pine further investigation must decide. There was an 

 increase in radial growth in the apical shoot and at the same time 

 a decrease below between June 3 and 15, but that growth ceased 

 first above cannot be deduced from the present observations. 



As regards the theory advanced by Friedrich concerning two 

 periods of maximum growth in trees, little can be said. The 



l 



second period if present in Pinus rigida must be the minor one, 

 inasmuch as the ring was on an average more than half completed 



on June 15. 



Width of the ring 



Measurements were made from sections of tree III to determine 

 the width of the ring at different heights. According to Hartig, 

 in trees in open stand the amount of wood formed increases from 



~~ a. « 1 rwvi • • - - . , • _ •*.%.*** 



may arise from 



may 



may be true. The latter, he says, is but 



sometimes 



From 



these observations it is to be expected that in Pinus rigida the ring 

 would increase perceptibly in width toward the base, inasmuch as 

 the crown is as a rule not exceptionally well developed. Such was 

 the case. At cuttings i and 4, the completed ring on February 21, 

 1910, was about the same width. At cutting 8 it was but 0.85 the 



further 



— — .„, ^^.w^, rfiiij.^ uutuing iz anuwcu. <x sun iuiuiw ^~~ — 



to o . 70. It follows that in Pinus rigida, if there is such a decrease 



from 



same applies with even greater 

 us and poorlv develooed crown. 



older 



