- 
254 BOTANICAL GAZETTE [OCTOBER 
same hour. It is very generally recognized that girdling interferes 
with the translocation of carbohydrates, and as a result thereof 
bearing plants very frequently produce extra large fruits which 
usually ripen prematurely. The production of large premature 
fruits is also a characteristic symptom of yellows, and it therefore 
appears that the physiological behavior of a tree affected with 
yellows is the same or very similar (so far as photosynthesis and 
translocation of carbohydrates are concerned) as in a tree that 
has been girdled. In trees affected with little peach, however, 
the symptoms, so far as the fruit is concerned, are just the reverse, 
the fruit being somewhat smaller and ripening later than normally. 
This may possibly account for the fact that sections of twigs from 
trees affected with little peach showed some evidence of trans- 
location of starch, while those from trees affected with yellows did 
not show any such evidence. These differences, however, may 
have been due to other causes, such as severity of infection, age of 
trees, or other factors. 
The preceding discussion indicates that the translocation of 
starch is greatly reduced, possibly completely checked, in trees 
affected with either of these diseases; or that have been girdled 
and injured by label wires, bores, or at the collar as a result of 
freezing. In all cases the results are an accumulation of starch 
in the leaves, which may account for the leathery texture, but does 
not offer an explanation of the willowy growth of the final stage 
of the yellows. If the translocation of carbohydrates is reduced 
or prevented, however, it may have a secondary effect on the 
tree, resulting in the willowy growth. 
Furthermore, the reduction or inhibition of the translocation of 
carbohydrates may also account for the enlarged premature fruit 
which is characteristic of trees affected with yellows, or that have 
been girdled, but it does not explain the undersized fruit and 
delayed ripening which is characteristic of trees affected with 
little peach. These facts indicate that some of the symptoms of 
these diseases are due to reduced or inhibited translocation of 
carbohydrates. The cause of this condition is a question that 
remains unanswered. 
