MICHIGAN ACADEMY OF SCIENCE. 159 



DOES THE MOVEMENT OF AIR AFFECT THE GROWTH 



OF PLANTS?^ 



BY ALMA HOLLINGER. 



There is a general opinion that plants grow better in moving air 

 than in still air. 



This opinion was tested in a series of experiments with plants. 

 The work Avas all done in a dark room. On one side there was a 

 shelf, at the end of which was an electric blower that kept a con- 

 tinual current of air moving over that shelf. On another shelf the 

 plants were kept under bell jars, thus excluded from all moving air. 



The first tests were made with seedlings, with the result that 

 after seven days the radish, lupine and buckwheat showed an 

 average gain of .23 to .93 inch in the current of air; the corn, several 

 varieties, showed an average gain of 3.9 to 5.4 inches in the still 

 air under the bell jars. 



The moisture was not controlled in these tests; the humidity 

 under the bell jars was 100% while that in the moving air was 

 much less. The temperature varied from 20° to 22° C. in the cur- 

 rent, while it was 1° to 2° C. warmer under the jars. 



In order to have the moisture conditions nearly equal, a third 

 set of seedlings was tested with the other two. These were placed 

 in a large wooden case closed, except on one side, five inches from 

 the wall. In these tests the moisture conditions were kept nearly 

 equal Avith those in the current of air. Again the greater gain was 

 in the moving air; here the corn, also, gained more in the current. 



The growth was not quite so rapid at first in the moving current 

 as in the still air, but continued for a period of two to five days 

 longer. When there was any noticeable difi'erence in the vitality, 

 it was greater in the moving air. The seedlings showed a deeper 

 yellow color, stronger stems and a little more leaf expansion. 



After a number of tests had been made with seedlings, green 

 plants were tested. Small potted Fuchsias were selected as near 

 the same size and vitality as possible. These tests were also made 

 in the dark room. One set Avas placed in the moving air, another 

 in the case and a third under the bell jars. This Avas repeated ; each 

 time the Fuchsias in the moving air gained a greater aA'erage length 



1. Abstract of papor. The papor will l>o printed in full only after the completion 

 of further investisations. 



