BROOKLYN BOTANIC GARDEN 
LEAFLETS 
Series 1 Brooklyn, N. Y., May 7, 1913 Number 5 
THE POLLINATION OF PINES 
The making of a seed is a wonderful process, as indeed are 
all the life processes of plants. With some plants the process 
occupies a few days only, with others a few weeks, while some 
plants require over a year to complete the work. Among the 
latter class are the pines. 
It is a matter of common knowledge that all seeds contain an 
embryo plant, and the so-called “germination” of a seed is 
essentially the resumption of growth of this embryo, after a 
longer or shorter period of rest. 
As is the case with animals, all plants are developed from 
eggs, or (in some of the lower plants) from the equivalent of 
eggs; but these eggs, as is also the case with animals, must, 
with a few exceptions, first be activated or fertilized by fusion 
with a sperm. 
The egg is formed in the pistil or carpel of the flower; the 
sperm in a portion of the stamen. In some kinds of plants, such 
as the elm, lily and violet, both egg and sperm are borne by the 
same flower; but in other kinds, such as the poplar, hop, and 
willow, the egg and sperm are borne on separate individuals. In 
still other plants (Indian corn, castor-bean, begonia, and others) 
both eggs and sperms are borne on the same plant, but by differ- 
ent flowers — the eggs by pistillate flowers, the sperms by stam- 
inate flowers. 
To the latter kind belong the pines, the commonly known 
(carpellate) pine cone bearing the eggs, which gradually develop 
into embryos. The sperms are formed within the pollen grains, 
which are produced in a second kind of cones, the staminate 
cones. The staminate cones are not as commonly known as the 
seed-bearing cones, but at this season of the j T ear, and usually in 
May in this climate, the staminate cones mature and shed their 
pollen. 
In the case of the pines, the pollen, which resembles a fine 
yellow dust, is carried to the egg-producing cones by the wind. 
Each tiny grain of pollen has two little air-sacs, or balloons, 
which make it very buoyant in the air. 
