THE QUADRAT METHOD IN TEACHING ECOLOGY 2G9 



imperative. Unfortunately, because of the usual arrangement 

 of the school year into semesters, field work by most students 

 can be carried on advantageously only for a few weeks in the 

 spring and fall. However, the accurate plotting of even one or 

 two quadrats always teaches a great deal to the student about 

 vegetation. Some of the more frequent lessons are: (1)' the large 

 number of species often represented in a single square meter, 

 (2) the surprising number of individual plants growing in so 

 small a space and the severe competition that must result, (3) 

 something of the life histories of species, gained by seeing indi- 

 viduals of the same species in different stages of development, 

 and (4) the necessity of knowing a plant, not only at the time of 

 anthesis or at maturity, but in all stages of its development, a 

 fact which invariably leads to closer observation on the part of 

 the student. But in spite of these gains such a procedure 

 frequently leaves the student with no knowledge of the greater 

 values of such a quadrat and with the impression that vegetation 

 is after all quite static. Could he visit these areas repeatedly 

 from year to year and rechart these quadrats, further values 

 would be gained. Among these would be: (1) the high mor- 

 tality among certain individuals and the general difficulty of 

 ecesis in rather stabilized areas, (2) the ephemeral nature of cer- 

 tain species as contrasted with the stability of others and (3) 

 hence the variations from year to year, (4) the value of scientific 

 accuracy in the use of the quadrat method, and especially would 

 he profit by (5) the dynamic view of vegetation which such an 

 investigation affords. 



In order that students pursuing ecology for even a single year 

 might derive many of the advantages of repeated yearly visits to 

 the field the following plan of the employment of permanent quad- 

 rats of various types, in prairie, salt flats, woodland, and ruderal 

 areas has been followed for the past three or four years. The 

 results, from both a pedagogical and a scientific standpoint have 

 been most gratifymg and it is felt that it might be worth while 

 presenting some of these data here. These data collected ahnost 

 entirely by students have in every case been checked bj^ a second 

 student and the writer vouches for their general accuracy. 



