4 ASSOCIATED SEEDS, INC. 
CORN 
Zea mays 
Until recent times, the development of corn varieties adapted to particular purposes 
and conditions of growth depended on natural mutation and selection by growers. 
Now, however, the new science of plant breeding has been applied to the building of 
hybrid varieties, with most satisfactory results in uniformity, yield, disease resistance, 
and adaptability to the soil and climate of definite areas, so that each season the pro- 
portion of hybrid corn is steadily increasing over that of the old open-pollinated types. 
A hybrid is defined as the first generation of a cross between strains of different 
parentage and involving one or more inbred lines or their combinations. A single 
cross hybrid is made by crossing two inbred lines, and a double cross from the 
mating of two single cross parents. A three-way cross comes from an inbred and 
a single cross. A top cross has for parents an inbred and an open-pollinated variety; 
a double top cross has a single cross and an open-pollinated variety for parents. Of 
these five types the double cross hybrids are most generally used. 
The purpose of inbreeding, that is, the fertilization of plants with their own pollen, 
is to emphasize desired characters such as size, shape, uniformity, disease-resistance, 
etc., and to eliminate those that are undesirable. Continued inbreeding of a single 
group of plants requires a high degree of skill, patiently exercised for years and with 
the possibility that it may not lead to profitable results. The next step is crossing 
by means of controlled pollination, which must be conducted with equal care. The 
first generation seed of any hybrid gives the maximum benefits from hybridization. 
The next generation, however, is not satisfactory for seed, as the hybrids are unstable 
in reproduction and begin to break up into the original and diverse lines from which 
they were developed. 
From the foregoing, three deductions follow naturally. (1) Hybrid seed must be 
procured anew each year, not saved. (2) It is bound to cost a little more, though it 
more than amply repays its cost. (3) It should be obtained only from a trustworthy 
and completely reliable source, since its value cannot be judged by its appearance. 
The following list comprises, first, a comprehensive selection of the open-pollinated 
varieties which experience has shown to be best adapted to the needs of Texas and 
other Southwestern growers, followed by six outstanding hybrids developed through 
a program of breeding, selecting and testing by the Texas Agricultural Experiment 
Station. Others are in course of production and will be announced when available. 
We confidently recommend them for trial by our customers, predicting increased 
yields and greater uniformity, easier harvesting, and improved quality of grain for 
milling and feed. 
The number of days indicated for each variety represents the average over different 
areas and different years. These figures are naturally subject to variation and are 
primarily intended for purposes of comparison. 
Varieties marked (y) have yellow kernels; those marked (w) have white. 
OPEN-POLLINATED VARIETIES 
CHISHOLM REDCOB (w) 
An old variety valued for its milling qualities and also for feed. Stalks tall 
and strong; ears have 14-16 straight rows, with ample husk coverage; kernels 
white, not hard, long, rough dent; cob dark-red. For early planting only. 
120 days 
DROUGHT RESISTER SURCROPPER (w) 
Similar to White Surcropper in ear and grain character. Grains mature com- 
pletely on a relatively low amount of moisture. Adapted to early and late 
planting to escape drought; used to some extent for early roasting ears. A 
good milling corn with relatively high shellout percentage. 115 days 
MEXICAN JUNE (w) 
Introduced from Mexico, widely adapted throughout the South and Southwest for 
very early and late planting. More prolific and productive under dry atmospheric 
conditions than other open-pollinated varieties. Responds to irrigation. Plants 
strong, sturdy, slender, often showing bluish-green color; ears medium, 12-14 
rowed with long, coarse, tight husk; kernels white, medium-sized, with a few pur- 
ple; somewhat chalky to slightly hard. Often used as a catch crop after oats and 
other spring crops. 120 days 
