Apr. i, 1921 
Growth and Sap Concentration 
9 i 
Taking account of the moisture factor thus reduces the coefficient from 
— 0.628 to —0.525. 
SAP CONCENTRATION IN APICAL AND BASAL REGIONS OF APRICOT 
SHOOTS 
Determinations of sap concentration were made at weekly intervals 
between June 12 and December 4 in the leaves and stems of a 10-cm. zone 
at both base and apex of apricot shoots. The concentration, as deter¬ 
mined by the lowering of the freezing point, is shown graphically in 
figure 5. 
It will be seen that the sap in the apical portion of the stem was more 
concentrated than that in the basal region. Increases or decreases in the 
Fig. 5.—Graph showing seasonal variations in sap concentration in apricot shoots. 
0 = sap concentration of apical io cm. of stems. 
A* 5 sap concentration of basal io cm. of stems. 
□=*sap concentration of leaves from io-cm. zone at apex. 
+=sap concentration of leaves from io-cm. zone at base. 
one are approximately parallel to increases or decreases in the other. The 
greater divergence in the last observations is probably due to the dry 
condition of the samples and to the possibility of error in one or both 
determinations. In general, the differences between results were suffi¬ 
ciently great to indicate differences well outside the realm of experi¬ 
mental error. 
The sap concentrations of the leaves from the different regions show 
no wide nor consistent differences, though there is a tendency for them to 
vary in opposite directions—that is, when one rises the other falls, and 
vice versa. In general, the sap concentration of the leaves was well above 
that of the stems at corresponding periods, a relation which was pointed 
out by Heald (6). 
