Sex was in the air all over Pass Island and West Beach at Deception Pass State Park this weekend. Bright red female Douglas-fir cones standing tall on branch tips were calling out to the pollen-laden male cones hanging below. “Hit me with some of your dusty golden pollen,” they seemed to be saying. And with every stiff branch-shaking breeze (or human hand) the air would blaze with the pixie dust so essential to the Pseudotsuga menziesii mating ritual.
Courtship among trees is obviously a bit different than it is among more mobile species, but the basic process is the same. Sperm and egg come together, fertilization occurs, and a new member of the species begins to grow. The female, carrying the eggs, somehow has to attract the male. Plants have evolved myriad ways for this to happen, often involving third parties like insects or other animals.
Conifers are wind-pollinated. Look closely at the Douglas-fir bough. There are just a couple of red female flowers near the branch tips while there are many more males hanging down below. Since cross-pollination, mixing genes between individuals, is valuable in a long-term evolutionary sense the species has developed a mechanism to keep self-fertilized embryos from completely developing into viable seeds. I don’t understand just how that works. Try a web search on “Pseudotsuga self fertile” if you want to figure it out.
The female cones are standing upright, presumably to make it easier for the wind-borne pollen to be ensnared as it drifts by. Once the flowers are fertilized then the cones will turn downward, which is the way we usually see Doug-fir cones on the tree.
This weekend was the first time I’d noticed Douglas-fir in bloom after nearly 20 years of seeing this most common of northwest conifers. Why hadn’t I noticed it before? Probably just not in the right place at the right time. I know I’ll be looking for them in the future.
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