
Number of Type la--Intermittent areas. 
potholes Type lb--Temporary marshes, 
Type 3--Shallow marshes. 
300 I-A Type }--Deep marshes. eee 





Type 5=-Open water. i950 
250 






250 
200 200 
150 150 
100 100 
50 50 
wre ws 
Sen So 
0 0 
400-4 400 
350 350 
300 300 
250 250 
200 200 
150 150 
100 100 
50 50 
Bis ue oy é - at 2 S eels 
r¢) Pe ae 2 rae he AE Sew , 6 
Apre 10 May 10 June 9 July 9 Aug. 8 Sept. 7 Oct. 7 Nov. 6 
Figure 9.--VARIATION IN NUMBER OF POTHOLES WITH WATER, WAUBAY STUDY 
AREA, BY PERIODS, 1950 AND 1951 
18 
