At Christmas time, pine cones are everywhere.
They appear on wreaths, mantelpieces, tabletop displays and on Christmas trees. We spray paint their plain brown exteriors, transforming them into glittering, exotic jewels, if only for a month or so. We dress them up like little animals or hang them, streaming with ribbons, from the chandelier.
But what are these woody, spiky, resinous things that fall from the evergreens just in time to festoon the season?
Too often we dismiss the sticky, scaly pods as nuisances. They land in the driveway or choke the gutters. The yard is full of them every couple of years, necessitating a major clean-up.
But a little appreciation for these ancient seed-bearers is called for. They have appeared in arts and crafts throughout the ages, a symbol of eternity and enlightenment. Their prominent place in Christmas décor leaves out the storied journey that brings them to rest in our homes for six weeks of the year.
When visiting my brother in South Carolina a few years ago, I filled a box with the enormous pine cones dropping from the longleaf pines in his yard. Compared to the pickings from my spruces and white pines, these were prize cones, huge enough to decorate like little trees. At the other end of the spectrum are the dainty hemlock cones, like tiny wooden flowers gathered by the handful, or the hard blueberry-like juniper cones so prized by the birds.
Sizes and Seeds
Pine cones vary in size according to the type of conifer but they are unique to gymnosperms, plants that don’t produce flowers or fruit. Instead, they produce a “naked seed,” (translation of gymnosperm), that is housed within the cone’s scales.
If you’re picking up a pinecone from the ground, you’re picking up a female cone. Males are inconspicuous, clustered and deteriorate quickly after their pollen has wafted upward to the females, located toward the top or branch tips of the tree.
Pollen floats on the wind to the tiny female cone and lands on sticky fluid near the tip of the scale. The scale tip opens slightly to let the pollen into the cone, where it rests for a year. The female cone grows through the summer into a hard green structure with the scales held tightly together with resin. Fertilization won’t occur until the next spring. Once that occurs, the female cone grows as the seeds mature, getting larger and browner.
The stem that attaches to the branch of the tree continues through the entire length of the cone and multiple scales arise along its length in a spiral pattern to create the characteristic fish scale appearance of many species. Interestingly, pinecone scales follow the Fibonacci number ratios.
When the seeds are mature, the scales begin to separate from each other, becoming brown, dry and woody. Between the scales, two seeds rest atop each scale. In some species, the cones open at maturity and the seeds are released. In others the cones remain closed for several years until opened by rotting, food-seeking animals or fire.
A pine cone will go through many cycles of opening and closing during its life span based upon moisture content; cones are usually open when dry and closed when wet.
This puzzled me on the trip back from South Carolina with my trunk full of longleaf pine cones. I gathered them up full and open, tossing them into the box with abandon.
When I arrived home to chilly Delaware, they had closed up to half their size, a process repeated as long as I left them outside. Once inside they settled into their open shape and I placed them on shelves, wrapped in lights, where they will be this year.
Article from Delaware Online.