270 MASS. EXPERIMENT STATION BULLETIN 171. 



Asparagus Stalks. 



The marketable portion of the asparagus plant consists of the young 

 stalks cut from the crowns during the spring and early summer. Their 

 constituents must be mainly derived from the reserve materials stored 

 the previous summer in the roots, and the total quantity removed in a 

 season represents the drain which the roots must be prepared to meet. 



Our first samples of young stalks were obtained from the experiment 

 field at Concord in 1910, but it was clearly evident that during the two 

 or more days which elapsed between cutting in the field and delivery at 

 the laboratory there were destructive changes taking place in the soluble 

 carbohydrates or sugar of the cells. Consequently in the spring of 1911 

 a series of samples of young stalks was gathered from the experiment 

 field at Amherst, which had been fertilized in a similar manner to the 

 field at Concord. 



Samples of stalks were cut from four different plots in the home field 

 on four different dates, beginning May 17 and ending June 14. The stalks 

 were cut as close to the crown as possible, and averaged about 10 inches 

 (25 centimeters) in length. The common practice of asparagus growers 

 in Massachusetts is to grow the crop so that most of the stalk is above 

 ground, and when trimmed to the standard length of 8 inches (20 centi- 

 meters) it is nearly all green. The material used in our investigation rep- 

 resented the crop as cut from the crowns before it is bunched and 

 trimmed. Each plot sample consisted of all the stalks which were tall 

 enough to be marketable on the day of cutting. 



Immediately after the samples were cut they were taken to the labora- 

 tory, where the stalks were wiped with a dry cloth to free them from 

 adhering soil, after which the samples were weighed. The stalks were then 

 broken into short pieces and spread on a tray which was placed in the 

 steam-heated drying oven at a temperature of 55° to 60° C. 



In preparing asparagus stalks for analysis it was found necessary to 

 avoid a large amount of cut or broken surface, since the contents of the 

 ruptured cells changed rapidly during the early drjdng stage by a process 

 of fermentation with a loss of soluble sugar. Too high a temperature 

 would soften the tender tips or buds of the stalks and cause them to stick 

 to the tray. Pieces of stalks about 3 inches (7.5 centimeters) in length 

 withered quickly in a temperature of 55° to 60° C, and at the end of 

 twent3^-four hours the largest butts were split in half, longitudinally, to 

 promote further rapid drying. Samples dried in this manner were subse- 

 quently found to have retained their sugar unchanged, or at least under 

 such conditions there was obtained the maximum proportion of sugar. 



Composite samples from all plots represented each date of cutting, 

 in order to determine the rate of change in their composition as the season 

 advanced. The following table shows this composition; — 



