POACEAE (Grass family)

                                                           
                                                            
 
Grass family botanically known as Poaceae, it contains about 10,000 species of which 1,200 occur in North America. This family is ecologically the most dominant and economically by far the most important in the world.
 
FLOWERING  
In the temperate zone grasses flower predominantly during the summer months, although a number begin flowering in the spring and some extend well into autumn.
  POLLEN MORPHOLOGY  
Pollen grains are spheroidal to ovoidal sometimes ellipsoidal to subellipsoidal. Monoporate, the pore usually circular to ovoidal, occasionally transversely ellipsoidal surrounded by a thickened protruding (annulus), and covered by an operculum that either smooth or granular, the pore margin smooth or wavy, with the largest grains provided with the largest pore. Ovoidal grains usually have the pore at the broader end.
 
AEROBIOLOGY AND ALLERGENICITY
 
Grass pollens can be reported from the ambient air as well as indoor air during aerobiological survey especially during the pollen session. Grass pollinosis is important in North America it is usually second only in significance to late summer effects of ragweed allergenicity. Some common genera include bahia grass, barley, beachgrass, bluegrass, buffalo grass, corn, couchgrass, maize, reedgrass etc.