272 MASS. EXPERIMENT STATION BULLETIN 171. 



the first rapid development in warm days of May, giving more time for 

 the photosjTithesis to go on. It does not seem reasonable that the drain 

 on the roots should be inversely proportional to the reserves in them. 

 The decrease in nitrogenous matter does follow the exhaustion of the 

 roots. The change in protein is a steady decrease in the amino nitrogen, 

 while the true protein remains practically constant. This points also to 

 more self-support and slower growth. 



Asparagus Tops. 



The development of reserve food material by the asparagus plant has 

 been studied by the analysis of samples of fully grown tops in midsummer 

 and ripened tops in late fall. Two series of samples were collected from 

 the fertilizer plots at Concord, — one in October, 1911, and the other in 

 August, 1912. These were taken for the purpose of ascertaining whether 

 the reserves were affected in any manner by the different fertihzers em- 

 ployed. Upon analyzing them it was noted that soluble carbohydrates 

 were very low, and the possible destruction by respiration during the 

 time required to transport the samples from Concord to Amherst led to 

 taking parallel samples at Amherst for the study of their composition at 

 the two stages of growth. 



To avoid serious injury to the crowns, representative samples for each 

 stage of growth were obtained by pulling only one stalk from a crown. 

 Seven average plants yielded in this manner an abundance of material 

 for a sample, and two parallel samples were thus selected on the different 

 dates. 



To ascertain how fast translocation of reserves was taldng place the 

 tops were divided into two portions. Each top was trimmed to a single 

 stalk and thus was formed two samples, — stalks and branches. 



The lot of tops was weighed as soon as removed from the field, then 

 divided into stalks and branches, each portion being weighed. Each 

 separate sample was now spread in the sun in the glass house for twenty- 

 four hours, and then run through a fodder cutter. The samples were 

 next dried in the large steam-heated oven until brittle enough to be ground, 

 when they were cooled in the air, weighed and pulverized for subsequent 

 analysis. 



The summer stage of growth was after blossoming was about over, 

 and the stalks chosen bore no berries. This stage was considered by 

 analogy with other crops to be the stage of maximum growth of tops, 

 and that the reserve material in the tissues would be at the maximum. 



The ripened stage was when the stalks had turned yellow and the 

 needles were falling from some of the stalks. The tops selected were 

 those wliich shed but few when handled. 



