A-Birding on a Bronco contains the author's notes taken at Twin Oaks in Southern California in spring and summer of 1889 and 1894. During her rides she met more than 50 different bird species. She recalls her daily routine as follows: 'Every morning, right after breakfast, my horse was brought to the door and I set out to make the rounds of the valley. I rode till dinner time, getting acquainted with the migrants as they came from the south, and calling at the more distant nests on the way. After dinner I would take my camp-stool and stroll through the oaks at the head of the valley, for a quiet study of the nearer nests. Then once more my horse would be brought up for me to take a run before sunset; and at night I would identify my new birds and write up the notes of the day. What more could observer crave?'