How Does a Pine Tree Reproduce?

Pine trees carry two types of cones--large "woody" female cones and the smaller grainy male cones. The female cones are formed at the upper half of the foliage while the males grow on the lower branches. Most pines are considered monoecious because of their hermaphroditic nature and proportionate dispersion of both types of cones. However, some species produce a lopsided amount of one cone type and for that reason are classified as sub-dioecious.

The male cones are composed of small, pollen-filled grains covering the cone. At maturity, the light pollen "sacks" break away from the cones and drift through the air with the goal of reaching the core of the female cone.

The female cone begins like a flower bud. In the spring time, the cone opens up its wooden petals and then it falls to the ground. The opening of the cone renders the female ready to receives the airborne pollen from the males.

The pollen grains are received into the open coned and then closed to commence fertilization--the cone won't reopen until at least the next spring. The pollen injects a tube into the ovules around the core of the cone and the two structures fuse to form seeds.

When the cones finally reopen--some take years and others never open--the seeds are equipped with a paper-like wing. The wing allow the seed to carry through the air and spread the seeds away from the tree.

Resources

• Types of Pine Trees