Allergic to Pollen?

Plants with drab or small, insignificant flowers, like sedges, grasses, trees and some herbs are dependent on the wind to spread their pollen to other like individuals. Wind-pollinated plants usually produce copious amounts of pollen, effectively spread on dry, windy days. It is reported that one ragweed plant can produce 1 billion grains of pollen!

Hay fever is the result of the body's production of immunoglobulin and histamine on exposure to triggers. The eyes and the nose may be sensitive to the barbs on the pollen grains triggering the reaction. There is some seasonality to the reactions, coinciding with the release of pollen by specific types of plants.

Winter and early spring see the pollen release on the conifers: spruce, pine, cedar, larch and fir. These are followed by the broad-leaved trees in the northeast: willow, poplar, birch, maple, ash, beech and oak, all producing pollen in April and May.

For those whose misery does not begin until May and June, grasses may be your trigger. This includes lawn and turf grass, in addition to sedges and other narrow-leaved similar plants. Mowing lawns may require a mask, or a helper!

Late summer and fall belongs to the ragweed, the scourge of the continent for most sufferers. Unfortunately, goldenrod bears the blame, an untruth as goldenrods are insect-pollinated. They just happen to be showy at the same time, that the messy green ragweed appears roadside and in ditches and gardens.

Late fall and winter hay-fever may be caused by other agents, but if you use evergreens in your house during the holiday season, wreaths and boughs may be covered in pollen, long after ragweed as died down for winter.

Outside plant allergies are difficult to avoid. Following the pollen reports can inform those afflicted when to take precautions. There are several weather websites that give daily pollen reports.

Got plant questions? Join us on Twitter Tuesday May 19, 11:00-12:00 ADT for Ask a Curator hour.

Jack Pine, Pinus sylvestris, staminate flowers, photo by Martin Thomas
Pollen catkins, Poulus tremuloides,Trembling Aspen, photo by Martin Thomas
Blue-joint Grass, Calamagrostis sp. photo by Ross Hall

Ragweed, Ambrosia artemisiifolia, photo by Ross Hall

Large Goldenrod, Solidago gigantea, photo by Martin Thomas