2 BULLETIN 806, U. S. DEPARTMENT OF AGRICULTURE. 
data, which show the-distribution on a tree basis, are reduced in these 
maps to an acre basis for convenience of expression. As in figure 1, 
nectarines, which are grouped with peaches, are of such small impor- 
tance as to be without substantial effect on the peach data. 
ESTIMATED PRODUCTION OF PEACHES. 
The estimates of the annual production of peaches for the years 
1900 to 1919, inclusive, appear in Table L. 
The estimates for the years 1900 to 1908 are based on the census re- 
port for the crop of 1899, while for the years 1910 to 1919, inclusive, 
they are based on the census figures for the crop of 1909. : 
The variation in the size of the peach crop from year to year is 
shown in figure 4. While al! census data as well as estimates based 
MILLIONS OF ACRES FRUIT MILLIONS OF DOLLARS 
3 2 ! C10Meeeo Oman 
ES ELS APPLES 
—— PEACHES & NECTARINES 
GRAPES 
STRAWBERRIES 
ORANGES 
PLUMS & PRUNES 
PEARS 
CHERRIES 
LEMONS 
APRICOTS 
POMELOS 
CRANBERRIES ~ 
Fic. 1.—Diagram showing the relative importance, acreage, and crop values of the 
principal fruits of the United States for the year 1909, based on the report of the 
Thirteenth Census. (From the Yearbook of the Department of Agriculture for 1915.) 
on those data are expressed in terms of the total crop, including both 
home consumption and the commercial crop, the annual variation in- 
dicated suggests also the fluctuating character of that portion of the 
crop which enters into commerce. 
Climatic conditions doubtless are the most potent causes of large 
annual variation in the size of the crop. Most important of these 
are adverse winter temperatures and the occurrence of spring frosts 
during the blossoming period. In addition, warm periods during the 
winter often cause the fruit buds to start enough to become tender. 
In this condition they are likely to be killed later, even by tempera- 
tures that are not unseasonable. On the other hand, the effect of a 
frost during the blossoming period is not always in proportion to its 
severity, but depends to some extent upon the strength and vigor of 
the blossoms themselves. 
