A CHEMICAL STUDY OF THE ASPARAGUS PLANT. 287 



draws continuously tlirough its roots on the soil for its required mineral 

 matter while building up its organic matter in its green branches. There 

 has been probably but little transfer of sugars and proteins to the roots 

 during this growing time, and it seemed as if any effect of the fertilizers 

 on the formation of those constituents should be perceptible at this season. 



The material for this study was gathered from the experiment field at 

 Concord by the selection of samples of tops from eight of the fertilizer 

 plots, which represented wide variations in the method of fertilization. 

 In order to disturb the subsequent growth of these plots as Uttle as possible, 

 not more than one stalk was removed from any plant. Each sample con- 

 sisted of six stalks selected from as many typical plants on a plot. The 

 samples were weighed immediately after being gathered, and were then 

 packed in burlap sacks for shipment to the laboratory at Amherst. The 

 samples were gathered on Aug. 13, 1912, and were deUvered at the labora- 

 tory forty-eight hours later. 



On the arrival of the samples at the laboratory they were again weighed 

 and were found to have lost 13 per cent, of their field weight, of which loss 

 a large part must have been due to respiration and the consequent destruc- 

 tion of sugars. The branches were cut from the main stalks, and the 

 latter broken in short pieces to facilitate drying, which was carried out by 

 spreading the samples on benches in the greenhouse. It was not possible 

 to dry all the samples simultaneously in the oven, so the greenhouse was 

 selected as providing uniform conditions for them. At the end of five 

 days each sample was cut into short lengths by a fodder cutter, after 

 which a small subsample was separated by quartering. 



The small samples were next dried in the oven until they were in a 

 condition to be easily ground, when they were pulverized and passed 

 through a millimeter sieve. 



Weights of Samples of Green Tops (Pounds) . 



Plot 1 5.25 



Plot 5 6.60 



Plot 9 6.25 



Plot 11 6.75 



Plot 31, 6.25 



Plot 32 6.25 



Plot 34, 6.15 



Plot 35 5. 65 



The absence of nitrogen on plot 1 and of potash on plot 9 was accom- 

 panied by the Hghtest weights of samples. Plots 11 and 34 received equal 

 amounts of the complete fertilizer in the spring, and their samples ex- 

 ceeded in weight those of 1 and 9. The absence of phosphoric acid from 

 plot 5 did not affect the weight. 



Just before the needles had dropped in the faU was selected as another 

 stage at which to study the effect of the fertilizers on the composition of 

 the tops and on the development of reserve material. For tliis purpose 

 Mr. Prescott was asked to procure some samples from the Concord field. 



