LUTHER BURBANK 
ter-inch or at most a half-inch in diameter. Thus 
placed, they will begin bearing in from two to 
four years; whereas if placed upon the large 
branches a much longer period would be required. 
By this method I have tested as many as 526 
varieties by actual count at the same time upon a 
single tree. 
Thus twenty thousand or more varieties may 
be tested at once on a single acre. The same trees 
may serve in this way over and over indefinitely. 
It would be well if fruit growers in each geo- 
graphical section would raise and test new seed- 
lings, and also introduce and experiment with 
new varieties produced elsewhere, aiming always 
to select those best adapted to the requirements 
of the particular locality. In this way many lo- 
calities where the apple cannot be grown today 
might produce thriving orchards. 
MAKING Harpy APPLES 
The apple is relatively hardy, but improve- 
ment is still possible in the way of producing va- 
rieties that will stand the excessive cold of our 
northern winters. The work of crossing hardy 
Russian apples and also the hardy American crab 
with the better varieties of apples is now being 
carried on quite extensively, especially in Iowa. 
By this means some good varieties have been pro- 
duced that are especially acapted to withstand the 
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