364 READINGS IN BIOLOGICAL SCIENCE 



nose-tickling pollen. But ragweed is the most important. We can pin this 

 statement down with a dollar sign, because commercial drug houses make 

 up their autumn "treatment kits" with ragweed. 



The pollen trapping idea of Dr. Blackley was a smart one. Today, pollen 

 catchers furnish advance notice of what is in the air. They measure the 

 amount of trouble on the way and identify the agent causing it. There is a 

 battery of pollen spotters, employed by specialists in allergy — some of 

 them in cooperation with the U.S. Weather Bureau. They learn which 

 weeds are coming into pollen-shedding season. They report that weeds 

 have their preference as to soil, rainfall, and climate, and chart the geo- 

 graphical distribution and trends of the various kinds. Today we have de- 

 tailed hay fever maps for each type of pollinosis. Spotters reach high up into 

 the air. Even in Blackley's time, he used tandem kites to make exposures 

 of his greased plates. The highest exposure was at 1500 feet. Fifty years 

 later airplanes were used to make pollen concentration studies. Today there 

 is an elaborate network of aids to allergists throughout the United States. 



Ragweed is high in the index of our national pollen count, but so are 

 grasses. Grasses are so much a matter of everyday life that most people 

 do not think of them as a possible source of trouble. Trees are possible 

 sources of trouble. Male and female trees may be miles apart. Nature has 

 made it imperative that enormous amounts of pollen be shed to make sure 

 air borne messages may reach the lady. 



But it is never the grass, or the tree, or the flower that makes the trouble. 

 It is that ole debbil pollen riding the wind and reaping a whirlwind of 

 sneezes. 



Pollen granules are formed in the male organs of plants. Their function 

 is to fertilize the seed. Not a single fertile seed can form in any one of our 

 flowering plants unless a grain of pollen has carried the spark of life to the 

 undeveloped seed.* 



It is the drab, uncolored plant, which the allergic person has probably 

 passed by unnoticed, that produces unbelievable amounts of light, dry 

 pollen. The bee snubs it, too. Ragweed has to depend upon the wind to 

 deliver its pollen, and the wind carries it high and scatters it far and wide. 



When you consider the hit or miss method of sending pollen grains in 

 the air for fertilizing eggs, the reason for the high rate of overproduction 

 is apparent. Even in an ordinary ragweed patch, enough pollen has to be 

 poured out to hit a mark the size of a needle point twenty blocks away. 

 Nature's office of production management runs her air force on a scale 

 that puts humans to shame. There are no bottlenecks. 



A single well-developed short ragweed plant has been watched and 

 found to produce one million 7Jiillion polleti grains. Under observation, a 

 giant ragweed produced about eight billion pollen grains in five hours. 



* The pollen grains contain the male sex cells or sperms which fertilize the egg in 

 the young seed, — EcJ. 



