WHAT IS HYBRID CORN? 
"Possibly the simplest way to give a general idea of 
what hybrid seed corn iS/ is to compare it to the mule. 
A mule is the first-generation cross between the mare 
and the ass, and partakes of the better qualities of both 
parents. It does not reproduce, but must be produced 
anew each generation, for its value is in itself, not for 
reproduction. A corn hybrid is the first-generation 
hybrid between two strains of corn. Its value is in the 
production of a crop of commercial corn. This corn will 
grow, but cannot be used for seed without a loss of 
yield in the succeeding generations. A corn hybrid, 
then, like the mule must be produced anew each genera¬ 
tion for its value in itself, not for reproduction. During 
that generation good hybrids produce larger acre 
yields of high quality corn than do most commercial 
varieties. Finally, neither all mules nor all corn hy¬ 
brids are efficient.” —U. S. D. A. Farmers’ Bulletin 
No. 1744. 
WHY KEYSTONE HYBRIDS? 
KEYSTONE FHYBRIDS are hybrids whose perform¬ 
ance, over a period of years, has definitely proved them 
to be superior producers in their respective areas of 
adaptation. They have been tested thoroughly by state 
agencies as well as in our own observation and yield 
test plots covering a wide area. Over and above these 
tests are the thousands of acres of KEYSTONE HY¬ 
BRIDS grown on individual farms, which is after all, 
the most important proving ground of all. 
The production of any good hybrid is based pri¬ 
marily on three important phases; namely, breeding, 
production, and processing. The highest possible 
standards must be maintained throughout all of these 
phases if the resultant product is to be of highest 
possible quality. Breeding must be done on a scientific 
scale, with complete and accurate records,- production 
requires the utmost in accuracy and efficiency,- and 
finally, the processing or grading must be done care¬ 
fully and thoroughly to insure that the farmer will 
secure an accurate drop and a uniform stand when the 
corn is planted. 
THE BREEDING BEHIND KEYSTONE 
HYBRID CORN 
Keystone Valley Farm, located in St. Louis County, 
Missouri, is the proving grou nd of all KEYSTONE 
SEEDS. Here, in addition to thousands of tests of 
countless varieties of garden and field seeds, is carried 
on a well organized program of corn breeding. Spe¬ 
cially trained men carry on a zealous search for new 
inbred lines which may aid in the improvement of 
KEYSTONE HYBRIDS. These new lines are crossed 
by hand in the breeding plots and the crosses thorough¬ 
ly tested in the observation and yield test plots. 
Standard inbred lines developed and released by the 
various State Experiment Stations also are used in an 
effort to find new combinations which will mean in¬ 
creased yield and more profit for the farmers who use 
KEYSTONE HYBRIDS. 
When a new hybrid looks promising in the observa¬ 
tion trials it is put in the competitive yield tests to de¬ 
termine its ability to perform in relation to hybrids 
already in production. If the new hybrid fails to per¬ 
form as well as those already in production, it is 
discarded. If it proves superior to the old hybrids, it 
is put in production and released for commercial use. 
Such a policy assures the consumer that new KEY¬ 
STONE HYBRIDS when released, are thoroughly 
tested and must be superior performers before they are 
sold for general use. 
Fig. 2. Breedins 
Plots on Keystone 
Valley Farm, where 
nearly 15,000 hand- 
pollinations are 
made annually 
ICORNEll 
KEYSTONE 
SeiECTEOl 
ClEANED 
TESTED 
i SEEDS 
i 
