18 
BULLETIN 79. HAWAII EXPERIMENT STATION 
to 3, inclusive). Type c is typical of a good smooth-shell tree, a 
large proportion of the nuts being grade 1. What poor nuts there are 
tend to be in group 6. Type d represents an extreme example of 
this tendency. This phenomenon might be ascribed to inherited 
characteristics or to early nutritional disturbances which later dis- 
appear since the distribution in the other groups is normal. Type e 
is a typical distribution for the rough-shell type. Whereas the 
smooth-shell type normally has few nuts in grade 2 (group 4), the 
rough-shell usually has a considerable percentage. This tendency 
to underfilling appears to be a characteristic of the rough-shell type 
rather than the result of nutritional disturbances. Type f shows how 
extreme this tendency may become with the rough-shell type. 
SEASONAL CHANGES IN DISTRIBUTION 
It has been previously noted that the crop varies in quality through- 
out the season, the first nuts which drop usually being poor in quality. 
If the tree is normal and in good condition, this represents only a 
small fraction of the crop. Sometimes this poor quality continues 
throughout the season. In table 9, tree No. 4 illustrates the rapid 
improvement in quality during the season, the bulk of the crop being 
borne during the last 3 months. With tree No. 10 the crop remained 
poor in quality throughout the season. This underfilling caused a 
marked decrease in the average weight per kernel and in proportion 
of kernel from that of the previous season. 
Table 9. — Seasonal changes in distribution in specific-gravity groups, smooth- 
shell type, Waipahu, Oahu 
Percentage of kernels having a grade and specific 
gravity of— 
Tree and month of harvest 
Proportion 
of kernel 
Average 
weight 
per kernel 
Grade 1 
Grades 2 
and 3 
<0.970 
0. 970- 
0.985 
0. 985- 
1.000 
> 1.000 
Tree No. 4: 
1930 average ... ... 
Percent 
28.5 
Grams 
1.87 
Percent 
13 
Percent 
70 
Percent 
12 
Percent 
4 
1931 
June... 
27. 6 
1.34 

1 fe! 
20 
79 
July 
27.4 
1.45 
1 
9 
26 
64 
August 
27.3 
26.9 
1.63 
1 
52 
23 
24 
September. . 
1.74 
14 
fi4 
12 
10 
October 
27.7 
1.86 
24 
70 
6 

November. 
27.6 
1.77 
20 
80 


Tree No. 10: 
1930 average 
40.7 
1.91 
41 
58 

1 
1931 
July.. 
36.8 
1.45 
6 
52 
14 
28 
August. 
35.7 
1.28 
2 
28 
26 
44 
September.. 
35. 9 
1.37 
7 
25 
23 
45 
October 
36.5 
1.37 
13 
25 
18 
44 
November 
37.5 
1.44 
20 
21 
18 
41 
December 
37. 1 
1.39 
19 
27 
16 
38 
YIELD AND NUT QUALITY OP SEEDLING TREES FROM DIFFERENT LOCATIONS 
Study lias been made over a period of years of representative trees 
from a number of the commercial orchards for the purpose of deter- 
