hybrids now in production. All new lines and new 
hybrids are thoroughly tested for a number of years 
before they are placed in production. If they do not 
prove in these tests that they are superior producers for 
a given area, they are discarded. 
Complete and accurate records are kept on each new 
line as it is grown from year to year. These records in¬ 
clude a complete history of the line, along with its reac¬ 
tions to various insects, diseases, and weather conditions. 
Similar records are kept on new hybrids in tests, in 
addition to accurate measurements of yielding ability. 
Thus, the breeding behind every Keystone Hybrid is on 
a completely modern and scientific basis. 
Growing: The actual growing or crossing of hybrid 
corn is one of the most important phases of its produc¬ 
tion. Extreme care must be used in planting, detasseling, 
and harvesting the corn, to prevent any mixture of stock 
seed at planting time, mixture by improper pollination 
or mixture of seed ears at harvest time. Careless methods 
of detasseling result in impure seed. 
Keystone Hybrids are produced by growers who have 
proven themselves to be qualified producers. Each 
grower is an experienced hybrid corn producer. He has 
been taught by Corneli’s agronomists and through years 
of experience, the principles which are so necessary to 
the production of good seed. Each field producing Key¬ 
stone Hybrid Seed Corn is under the direct supervision 
of trained agronomists and must pass rigid inspections 
over and over again before being accepted as fit for seed. 
Crews of experienced men go over the fields daily 
during the detasseling season and pull every tassel by 
hand. Each tassel must be pulled before it sheds any 
pollen. One shedding tassel in a field will contaminate seed 
ears for several yards in all directions, so the importance 
of thorough detasseling cannot be over-emphasized. 
Fig. 1. Taking Notes on Lodging After Heavy Rain 
and Wind. 
Extreme care is used in harvesting Keystone Hybrids 
to avoid any mixture of corn from pollen parent rows. 
Only ears from detasseled rows may be used for seed. 
Keystone Hybrids are grown mainly in the fertile 
bottoms of the Missouri and Mississippi rivers. Produc- 
Fig. 2. Production Field of Keystone 38 
After Complete Detasseling. 
KcornelTjI 
KEYSTONE 
SELECTED) 
l CLEANED J 
l TESTED! J 
I SEEDS i 
TDADE MAOK 
TESTIMONIALS 
1.—at present this section is extremely dry and my other 
hybrids are firing badly. Keystone 38 has not fired 
more than lower two blades and has large single ears 
of good quality, well filled. 
Albany, Missouri. 
2.—planted one bushel of Keystone 38 and gathered 520 
bushels of good, sound ear corn. This is extra good 
yield for this country and am highly pleased with 
the results. 
Grenada, Mississippi. 
