IN THE AVOCADO GROVES OF QUERETARO. 
(Persea americana Mill . See S. P. I. No. 46984.) 
The canyada, a narrow valley in the suburbs of the city of Queretaro, is 
one of the greatest avocado regions of Mexico. For a length of 2 
miles it is completely filled with avocado trees. Many of them are 
extremely old and large, but even the oldest produce fruit regularly. 
The cultural conditions under which they exist can be seen in this 
illustration. Water is turned over the soil every two or three weeks 
from small irrigating canals which run through the valley. The 
trees are all seedlings of the hardy Mexican race. (Photographed 
by Wilson Popenoe, Queretaro, Mexico, July 23, 1918; P17532FS.) 
