Pine cones are a familiar sight of winter landscapes; more correctly termed conifer cones in the botanical world, pine cones are more complex than they are given credit for at first glance. Most people are familiar with the woody appearance of the female pine cone. However, the male pine cone plays an important role in the continuation of the conifer species, despite its short life, and its less significant appearance. Female pine cones that have fallen from the tree are often used as winter time decorations for the Holidays.
Different Types of Cones in the Conifer Family
The conifer botanical division, Coniferae, is made up of eight plant families, the most familiar of which (with regard to pine cones) is the pine family, Pinaceae. However, all plant families within the Coniferae division are cone-bearing seed plants. They have similar looking spiky, needle-like leaves; examples include pine, fir, spruce, larch, juniper and yew. However, the cones (or seeds) produced by trees such as pine and fir are more woody in appearance than the cones of the juniper tree, which resemble fleshy berries. This article looks at the function and life cycle of cones produced by the Pinaceae plant family.
Function of Male Pine Cones
The Pinaceae plant family produces cones on the same plant (monoecious) unlike dioecious plants that produce separate male and female plants. Both male and female pine cones start out the same size. However, the male pine cone lasts only several weeks and, once it has released its pollen, it falls from the tree and dies. Pollen grains are formed in a pollen sac which develops on the scales of the male pine cone. When the pollen is released, the wind carries the pollen grains through the air where it might land on the scales of female pine cones.
Function of Female Pine Cones
Female pine cones develop at the same time as male pine cones but grow a lot larger; they also live for several years, as oppose to weeks. Female pine cones develop ovules on the scales of the cone. An egg cell is contained within the ovule; an embryo forms within the ovule if the egg cell is fertilized by the pollen grains of the male pine cone.
After fertilization, the ovule develops into a hard seed. The scales of the female pine cone are held tightly together by a form of resin, until the cone matures from green to brown and expands, allowing the seeds to drop. The seeds then develop into a new pine tree, given the right growing conditions.
Uses of Pine Cones After the End of Life
Female pine cones that have expanded, dropped their seeds and fallen from the tree are sometimes collected and used for Holiday decorations. Female cones from trees such as Ponderosa pine, white pine, Douglas fir and redwood, are used for Holiday tabletop decorations, gifts, wreath decorations and fragrance items. In addition, some female pine cones are converted into inventive bird and wildlife feeders. The female pine cone has a long life, even after its botanical life is over; the male pine cone is sadly forgotten in a few weeks.
References:
- Union County College website, Biology Department, Conifer Cones by Dr T Ombrello, accessed December 6, 2011
- Glendale Community College website, Gymnosperm Seed Plants – Conifer (Pine), accessed December 6, 2011
- Colorado State University Extension website, Identifying Conifers, accessed December 6, 2011
Sharon Falsetto - Sharon Falsetto is a business owner, certified clinical aromatherapist & professional writer with a life-long interest in plants.
