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Pollen grains of pine mg- nay lever. nuss is conifer pollen. If you park near pines you’ve probably seen it by now — a film of light-yellow, resinous dust that appears on your car overnight. Billions of pollen grains are produced by conifers during a few days in the spring, and then it’s all over.
What exactly is pollen
and what does it do?
Pollen grains are characteristic of all seed plants and can be found in geologic strata dating back to the Devonian. They can be identified by size, shape and various marks produced on the outside wall. Pine pollen is rather funny-looking with noticeable bladders like Mickey Mouse ears. Ragweed pollen looks more formidable with hundreds of little spikes on the outer wall.
BotanicaUy, pollen grains are not spores, seeds or gametes, but tiny multicellular male plants called gametophytes. Each has the % job of producing male gametes and hopeful- * ly fathering offspring.
In pines they are formed in clustered cones on lower branches of the tree. Separate ovulate (female) cones are formed at the same time, usually at shoot tips toward the top of the tree. Some wind-borne pollen grains fall on the female cone, where they lodge inside to await the development of female gametophytes. These females take a year to grow inside ovules, and after fertilization
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