Vol. XXII 

 1905 



1 Wood & Frothingham, Birds of An Sable Valley. A.I 



Mr. Gale and the writer started on a second trip from the town 

 of Roscommon, August 8, and floated the length of the Au Sable 

 River, — about three hundred miles, making the trip in fifteen days. 

 Kirtland's Warbler was not seen on this trip, although the localities 

 where it had previously been were carefully searched. 1 



The Au Sable River rises in the southwest corner of Otsego 

 County. It flows almost due south to Grayling, whence it bends 

 to the east. It receives two large tributaries in Crawford County, 

 viz.: the South Branch, rising in Roscommon County, some twenty 

 miles east of Roscommon, and the North Branch, whose head is 

 in Otsego Lake, Otsego County. Big Creek enters from the south 

 in Oscoda County, and the Lower South Branch in Iosco County, 

 and this completes the number of larger tributaries. The stream 

 drains a topography of glacial origin, and as a consequence fre- 

 quently cuts through morainal ridges, which give the river its steep 

 bare bluffs of sand or clay. These bluffs are usually crowned 

 with a thin turf bearing stunted jack pines and thick mats of sweet 

 fern. The bluffs alternate with areas of low land, known respec- 

 tively as cedar and hardwood swamps. The former consist of 

 thick stands of white cedar, balsam, spruce, tamarack, and birches, 

 in varying proportions. In the hardwood swamps white elms 

 predominate, associated with basswood, white and black ash, and 

 red maple. The banks are lined for long stretches with bushy 

 alders. At other places the bank vegetation is of saw-grass, wild 

 rice, milkweeds, golden-rod, cardinal flower, and sour dock, with 

 arrowhead, spatterdock, eel grass, and pickerel weed growing in 



1 During the summer of 1904 I made the following observations with regard 

 to the occurrence of Kirtland's Warbler in Crawford County. On July 21, 

 a male was heard and seen on the top of a high, sandy ridge, a mile north of 

 Higgins Lake. This ridge was covered w r ith an open sprout growth of red, 

 white and scarlet oaks, red maple, black cheery, june-berry, and prairie willow, 

 not over eight feet high. A heavy undergrowth of brake, sweet fern, and 

 huckleberry bushes completely concealed the ground. A pair of these birds 

 was observed at the same locality on successive days for at least a week, but 

 though they were seen with insects in their bills and gave every indication of 

 nesting, I was unable to find the nest. A second pair was observed July 22, 

 about a half mile from the above location, but these birds apparently were not 

 nesting. 



