Bayou-Diversity (25 March 2018) For the past several days I have been witness to an orgy, the likes of which would have titillated the goddess Aphrodite had she understood it. This reproductive frenzy is botanical in nature and is revealed by the clouds of breeze-borne pollen that blanket every horizontal surface.
Pollen is a powder-like substance containing the male sexual cells of flowering plants. Even in a small meadow or patch of woods, billions and billions of pollen grains are released for the sole purpose of procreation. For this to occur, pollen must come in contact with the female part of a flower of the same species. Barring compatibility problems, fertilization occurs and seeds are produced. Life goes on. In some species, the plant uses the pollen from its own flowers to fertilize itself. Other types must be cross-pollinated; that is, pollen from the flower of one plant must be transferred to the flower of another plant of the same species for fertilization to be successful.
Depending on the type of plant, pollen is usually transported either by the wind or by insects. Plants with large or showy flowers that attract insects often depend on them for pollination. Species with small plain flowers produce light, dry pollen grains ideal for wind transport. At least a quarter of a million plants use the wind for pollination. Herein lies the source of misery for untold numbers of allergy sufferers. The random flight of airborne pollen often ends in warm, moist human throats and noses triggering an allergic reaction known as hay fever. The chemical composition of pollen determines whether it is likely to cause problems. For example, pine trees in Louisiana are among the most prolific producers of pollen, yet the chemical makeup appears to make it less allergic than most. Local trees that do produce allergenic pollen include elm, ash, oak, hickory and pecan. Among grasses, Johnson grass and Bermuda are culprits. Those plants commonly referred to as weeds beget most allergenic pollen. Ragweed is infamous, but others of importance are pigweed, lamb's quarters, and plantain. Keep in mind that the wind commonly carries pollen for many miles so chopping down the pecan tree in the front yard is a waste of time, effort and pecans.
Pollen from different plants occurs at different times of the year in the various parts of the country. In bayou country, most trees produce pollen from January through March. Grasses reproduce from April through November, and weeds peak in the summer and early fall. Only December is relatively pollen free.
The local media often report daily pollen counts. This count is a measure of the concentration of pollen in the air at a specific time. Counts are usually highest on warm, dry mornings and lowest during chilly, wet periods. At best, counts are only indicators of the best time to stay indoors. As a diversion from the effects of a spontaneous sneezing fit, allergy sufferers should consider the sensuous nature of the pollen that caused it. (adapted from Bayou-Diversity: Nature & People in the Louisiana Bayou Country, LSU Press; photo by USGS)