FRANK C. GATES 
seedlings, growing unprotected in the open sun in an area cleared 
during the preceding winter (1914-15). In this same area three at- 
mometers were started in 19 16. The second year had allowed the 
brambles to encroach upon the fireweeds — clothing the ground with a 
dense covering of vegetation. The maple seedlings were likewise one 
year older and their vigor was positive proof that they were amply 
and easily meeting conditions. The introduction of cattle into the 
area in the middle of the summer necessitated the withdrawal of the 
atmometers. The healthy condition of the seedlings in the fall, 
however, was evidence that these seedlings could withstand even such 
an extremely dry summer as that of 1916. 
I0== Boe- SERIES: I9I6. ~ lo 
East Joint Series. Reese's Bog Series. /' \ 
27. Edge of dune. 31 .Clearing. / \ 
2?, Very dense part of bog. 33.Pense^ -no grecTi plaTita. / ^ 
30. Densest part, no green 34. Marginal foss, / \ 
plants. 35. Thuja seedling I71 dense part. / ^ 
41. Beach (One week), ^ \ 
37.Sla3ht pog east of Douglas Lake. / \ 
Fig. 4. Diagram showing the daily rate of evaporation in cc. for the intervals 
between readings from certain bog stations, 1916. The daily precipitation is shown 
on the same scale in cm. 
In 1915, atmometers No. 4 and No. 5 (Fig. 7) were run near maple 
seedlings in an area cleared in the winter of 1913-14. Weeds and 
brambles were also present. Atmometer No. 3 was run by maple 
seedlings in an open place in a thicket-tree growth — long since cut and 
lightly burnt — into which brambles have entered thickly. Atmometer 
No. 8, the last of this series, was run on Pine Point in a mixture of hard- 
wood and cedar in which all the large Thujas had been cut out. 
