Do Pine Trees Reproduce Asexually?
Pine trees and other conifers are members of a group of plants collectively called gymnosperms, which translates as "naked seeds." Like other gymnosperms, pine trees reproduce by sexual reproduction.
Features
Pine trees have both male cones called pollen cones and female, or ovulate cones. The pollen cones shed pollen grains into the wind, which carries the tiny grains to ovulate cones, where they will germinate.
Function
Once an ovule in a female cone has been pollinated, the megasporocyte hidden inside will begin to divide and develop into a gametophyte and eggs. Only once the female gametophytes are fully developed will the sperm from the pollen grain fertilize the eggs inside, at which point the ovule develops into a seed. The seeds are dispersed when the scales of the pinecone separate.
- Pine trees and other conifers are members of a group of plants collectively called gymnosperms, which translates as "naked seeds."
- Only once the female gametophytes are fully developed will the sperm from the pollen grain fertilize the eggs inside, at which point the ovule develops into a seed.
Considerations
The pollen and seed-bearing cones of a pine tree are analogous to the sexual organs of a flower. Even though the life cycle of a gymnosperm and a flowering plant are very different, both types reproduce sexually through the fusion of haploid gametes.
Fir & Pine Trees?
Similar in general form, basic differences exist between fir and pine trees, including botanical name, native ranges, and cone shape. Fir species number about 50, all native to very cold or mountainous regions in the Northern Hemisphere, and grow best in similar climates. They are regarded as trees. Pines can be trees or shrubs. Fir trees have relatively short needles, almost always less than 2 inches in length and occur singly on the stem in great numbers. Pine trees are also upright, but have more of an open, rounded canopy of foliage, sometimes loosely triangular but irregular, or looking like a jagged lollipop at maturity. They fall off after they release their pollen. Pine cones, the seed-producing female kinds, are seen at branch tips and point downward or horizontally.
- The pollen and seed-bearing cones of a pine tree are analogous to the sexual organs of a flower.
- Pine cones, the seed-producing female kinds, are seen at branch tips and point downward or horizontally.
References
- "Biology"; Neil A. Campbell, Jane B. Reece, Lisa A. Urry, Michael L. Cain, Peter V. Minorsky, Steven A. Wasserman, Robert B. Jackson; 2008
- Univ. of Wisconsin: Key to Wisconsin Conifers
- Univ. of Illinois: Key to the Conifers
- "A-Z Encyclopedia of Garden Plants"; Edited by Christopher Bricknell and H. Marc Cathey; 2004
Writer Bio
Based in San Diego, John Brennan has been writing about science and the environment since 2006. His articles have appeared in "Plenty," "San Diego Reader," "Santa Barbara Independent" and "East Bay Monthly." Brennan holds a Bachelor of Science in biology from the University of California, San Diego.