TWENTY-SIXTH SESSION. 
51 
Similar differences may be discovered in the trees of an apple or a pear 
orchard. I will give you the yields from three Winesap apple trees since 
1895. The trees stand together, resemble each other closely and have always 
received similar treatment. They differ chiefly in their fruitfulness. 
The trees may be numbered one, two and three. The figures represent the 
percentage of the total amount of fruit produced annually by each tree: 
No. 1. 
No. 2. 
No. 3. 
1895 
. . . 46 
21 
32 
1896 
. .. 48 
17 
35 
1897 
. . . 47 
9 
44 
1898 
. . . 41 
10 
49 
Average 
. . . 45.5 
14 
47 
A number of interesting things 
are indicated by 
these 
figures. First it is 
seen that trees 1 and 3 are uniformly heavy bearers and that tree 2 is a uni- 
formly light bearer. It is seen also that tree No. 1 is- approximately stable, 
varying not more than 7 per cent in four years, tree No. 3 is increasing in 
fruitfulness, while tree No. 2 has been decreasing in fruitfulness. These 
figures indicate that the individuality of a tree can be established only by 
recording its behavior for a number of years. The practical question is are 
these differences attributable to individuality, or to some unknown physical 
cause and will the bearing tendency of these trees be transmitted through 
their buds? 
Throughout the South the Le Conte pear is notorious for the variability of 
its individual trees which are grown from cuttings. The variations have 
therefore arisen as cutting or bud variations. At the Florida Experiment 
Station there are two distinct strains In the same orchard, one a prolific, the 
other a light bearer. Professor Rolfs, formerly at the Florida Station, informs 
me that light and heavy bearing strains are common in the Le Conte orchards 
throughout the South. A similar condition is equally true of the Kieffer 
orchards in the east. 
A Spitzenburg apple orchard has been under my observation for many 
years. Under intensive cultivation, fertilization, and spraying, it had produced 
ten consecutive crops of fruit up to 1898, when on account of continuous 
rains in the spring, the orchard could not be sprayed. The apple-scab fungus 
swept through the orchard and blasted the fruit in the blossom on every tree 
but one, which bore a large crop. The foliage was injured so severely that 
no fruit buds were formed for the crop of 1899 except on this one tree, which 
is again filled with apples. Here is a striking case of strongly marked indi- 
viduality in a single tree. The practical point is, could this tree be used as 
the starting point for the development of a strain of Spitzenburg apples less 
susceptible to the apple scab? 
Let us see what bearing these isolated cases have upon the discussion. 
They establish first of all this important fact, that the plants or trees of a 
given variety present endless variations, some of which may be useful in the 
highest degree to the fruit grower. 
The query that naturally follows is, Are these differences hereditary? For 
if they are, a basis is established on which the systematic improvement of a 
given variety may proceed. For all of organic nature has evolved by the 
accumulation of beneficial differences in successive generations. 
