16 BULLETIN 1104, U. S. DEPARTMENT OF AGRICULTURE. 
A study of the data presented in Table 5 shows that there was no 
clear-cut response to the fertilizer treatment as evidenced in the 
fruit. Certain observations on the effect of these fertilizers are 
worthy of note. Each year there was a markedly higher percentage 
of sound fruit in the nitrogen plat than in any other. The percentage 
of bad tissue browning in the fruit from trees of this plat, however, 
was also highest during the first season and second only to that of 
the manure plat the second year. In checking over the individual 
tree records on this plat, the remarkable fact has developed that 
during each year the trees producing the highest percentage of fruit 
which became badly browned were in this nitrogen plat. The foliage 
and general appearance of these trees have been the best of those 
under test, and generally the fruit has been either exceptionally good 
or exceptionally bad in its tendency to brown internally. These 
phenomena will be considered further under the subject of crop yield 
and browning. 
The phosphate and check plats have had only a moderate percent- 
age of browning. There has been little sound fruit, however. Gener- 
ally, the fruit has shown traces of browning, with little entirely 
sound and little particularly bad. 
On the whole, there has been a higher average percentage of brown- 
ing in the manure plat than in any other. The percentage of sound 
fruit has been low, and there has been an abundance of bad browning, 
particularly bad core browning, in the fruit. 
In general, it may be said that the results have been negative so 
far as causing or preventing browning through fertilizers is con- 
cerned. The points brought out are of interest, however, particularly 
when viewed in the light of the relationship of browning to yield, 
discussed later in this bulletin. 
RELATION OF INTERNAL BROWNING TO THE INDIVIDUAL TREE. 
During the early investigations of this trouble it was apparent 
that there is oftentimes a very distinct variation in the extent of 
browning which appears during storage in fruit from different trees, 
even when such trees are growing adjacent to each other. Conse- 
quently, for the past six years fruit from the different trees in the 
orchards under observation has been kept separate, and the average 
performance records of a large number of trees over a period of 
several years have been obtained. Only the summaries of these 
records will be presented here. 
It was in the minds of the investigators during the first years 
in which these records were made that the tendency of the fruit 
to brown in storage is a tree characteristic and that certain trees 
tended to produce fruit year after year that was inherently sound, 
while other trees regularly produced fruit that tended to become 
