Evening times-Republican. [volume] (Marshalltown, Iowa) 1890-1923, 1909-03-01

YIN order to continue to raise crops
from year to year we must propa-
gate the plants in some way.
There are two principal ways of
doing this-by seeds and by divisions
of the plant itself The most impor
tant of these is by seeds, as 1t is IN
this way that most of the ordinary
farm crops are multiplied.
In order to understand this process
we must first learn how the seeds ar
formed. The tasscl of the corn is TIL
male flower and the silk the female
Some plants, such as certain varietle
of Strawberries, have only femalf
flowers and must be planted in alter
nate rows with varieties which haM
both kinds OF blossoms. In othel
plants the male and female flowers
are combined in one. This Is the case
with the apple and many other fruits
Iii the apple the stamens, or male
parts, grow in ring around the pisti'
or female part, which is in the cente,
of the flower The top of a stamen
which is expanded, is called the an
Their. This contains a yellow dust
the pollen.
The upper portion of the pistil i.
called the stigma. From it tub;
called the style leads downward t.
the ovary. This ovary contains ont
or more egg shaped cells called ovules
Each Of these ovules Is capable of dc
yeloping into seed If fertilized witt
pollen grain. When a grain Of pol
len alights on ripe stigma 1t is hel'
by sticky substance secreted there
1t soon terminates and sends long
threadlike projection down through
the style to the ovary. This slender
projection enters the ovary, and the
resultant union Of the male and femal,
elements causes a seed to develop
One pollen grain is required for each
ovule, and each ovule develops into
separate seed. There are many thou
sand pollen grains produced by each
stamen, and as there are several sta
mems for each pistil you will see that
a great excess Of pollen is produced
This is one Of natures methods o.
making reproduction more certain.
In flowers like the apple the pollel
may sometimes fall directly on the
stigma in the same flower. More often.
however, the stamen and pistils ripen
at different times. The object of this
is to prevent self fertilization, which, II
long continued, will weaken the vitali
ty Of the coming generations. Cross
pollination-that is, the fertilization Of
the ovule of one flower by the pollen
from another plant-unites the strength
of both parents and produces larger
harder seed.
This has been proved by many exper
iments. If the tassels are pulled from
row of corn before they have time to
shed their pollen. the silks must neces
sarily be fortified by pollen from 9th
er stalks. The cross pollination viii!
cause the detasseled rows to produce
heavier and larger ears. If this proc
ess is continued from year to year the
yielding power of that particular strain
will be considerably increased.
In such plants as corn the wind car
ries the pollen for rods in every direc-
ton. The air in the cornfield is so
filled with the yellow dust that there is
seldom any danger that the silks will
fail to catch more than plenty to fer
tilize each OF the many ovules that are
to form the future kernels.
Some plants, however, are not so for
tunate in this respect. The pollen of
fruit trees is carried to some extent by
the wind, but not nearly so much so
as that Of corn. In such plants as