Pollen is male genetic substance of plant, trees, grass and weed, which is released from mature anthers during specific seasons which is lasting only several weeks of the year. Some plant species uses their own pollen sources from its flowers to fertilize itself. But in others species, it must be cross-pollinated to be successful.
This oval grains shaped pollen contained acute phase proteins which cause as allergen to certain people. Allergenic protein in pollen which caused hypersensitive reaction in our body. It enters our body through mucosal layer surfaces in skin. Due to the shape of pollen grain and its pores configuration, we can only make specifition possible under light microscopy.
Plant Pollens
Pollens that responsible for seasonal allergies are light and transported by wind. They emanate from plants with small, nondescript flowers. The “pollen season” varies by type of plant and geographic location but generally follows the order of trees, then grasses, then weeds. Pollen Airborne concentrations not only vary by weather conditions, but also with breezey condition, warm, and drybeing favored for pollen dispersal.
How pollen being distributed by plant can causing allergy to us? It is believed that pollens is disseminated in the air and accumulation in high pollen airborne concentrations in the air. Only this high concentration that will cause some allergic reactions to us. Some plants have produces a considerable amount of pollen grains that have aerodynamic properties to improve buoyancy. But there are other kind of plants (mostly flower) that are depend on insects or animal as vectors for distribute pollen, this is not pollen airborne vectors.
Pollens is calculated after accumulation in a standardized method applying machines that trap the pollen either actively on revolving arms coated with adhesive substances or with inactive wind and gravitation. Subsequently identification of the specific pollens to which the individual is sensitized, the published “pollen counts” could be a useful guide in addressing patients towards allergen avoidance and efficacious medicine utilization. Even so, the interpretation of these calculation and their relevancy to the human patient must be counted. For instance, day by day variation may be extreme, this will make interpreting for daily pollen symptom forecasting hard. Additionally, pollen symptom intensity depends upon lot of factors, so reporting of a doubling in pollen count, for example, may not be clinically relevant to an individual whose threshold level of allergen that causes symptoms has not been reached. Additionally, as someone sensitivity to exposure can vary over a season, with increased reactivity following a period by exposure, termed “priming.” In any case, knowing the patient’s particular sensitivities, the yearly timing of their pollen symptoms, the seasonal timing of pollenation, and the characteristics of local fauna will help to guide patient care.
Pollen Seasons
Pollen season are sorted as grasses, trees, and weeds. Gras pollen seasons is from late spring to mid-summer. Trees pollen seasons from late winter lasting till late spring. Weeds pollen season is from midsummer until autumn. But there are certain period of changes that is depend on geographic place location and annual weather pattern.
Tree Pollen
In north america, the beginning of tree pollen seasons (hence pollen allergy seasons) is in February to April. But in general, the fast concentration and great variety of tree pollens happen during March to May. In some area like Texas and Arkansas, tree pollen season may come as early December to January due to pollen from cedar trees (elm and red cedar). while mid- season pollinating species include poplar, birch, ash, and willow, with late-season pollination by sycamore, oak, and mulberry.
Trees that produce allergenic pollen include oak, ash, elm, hickory, pecan, box elder, and mountain cedar.
Grass Pollen
There are over a thousand of grass species in most areas on North America, but only a small percentage produce highly allergic pollen. Grass pollen season may overlap and come after tree pollen season. It is usually from May to July every year. There are cross allergic reaction and overlap among proteins from different grass pollen species. These include Bahia grass, Kentucky grass, Bermuda grass, redtop grass, orchard grass, and sweet vernal grass. The allergens in these southern grass pollens are distinguishable. In some subtropical areas Bermuda grass and other species may produce almost perennial pollination.
Weed Pollen
Weed pollen seasons commonly comes in the late summertime by October in most areas of North America. In that location there are a enormous diversity of weeds, but ragweed species (Ambrosia) are responsible to the biggest number of seasonal weed pollen allergy symptoms. A lot species of ragweed have cross-allergenic so allergic individuals may feel symptoms “out of season” once visiting a few areas wherever ragweed pollinates either perennially or in seasons away of the usual mid-August to ahead of October ragweed season, such as Coastal ragweed, which is prevalent in wintertime months in southern Florida. A different weeds responsible for substantial regional weed pollen allergy include pigweed, amaranth, marsh elder, dock, sorrel, plantain, and Russian thistle, among others.
