“In January one may follow a skunk track or search for bands of the chickadees, or see what young pines the deer have browsed, or what muskrat houses the mink have dug, with only an occasional and mild digression into other doings. January observation can be almost as simple and peaceful as snow, and almost as continuous as cold. There is time not only to see who has done what, but to speculate why.”

This quote introduces a central theme of the book, that of nature as teacher. By observing natural phenomena, Leopold is able to glean insights about the natural world that are not available in libraries and universities; moreover, he is able to see the connectedness of these phenomena, which is obscured within formal scientific disciplines. Finally, this quote introduces Aldo Leopold as both the author and a character who puts the importance of observing nature into practice in his own life.

“This same year 1871 brought other evidence of the march of empire: the Peshtigo Fire, which cleared a couple of counties of trees and soil, and the Chicago Fire, said to have started from the protesting kick of a cow.

In 1870 the meadow mice had already staged their march of empire they ate up the young orchards of the young state, and then died. They did not eat my oak whose bark was already too tough and thick for mice.

It was likewise in 1870 that a market gunner boasted in the American Sportsmen of killing 6000 ducks in one season near Chicago.

Rest! cries the chief sawyer, and we pause for breath.” 

Early in the book, Leopold meditates on how the rings in the trunk of a recently fallen oak tree correspond to years in American history; at the point of the passage in which this quote is found, he and another person have sawed through enough of the trunk that they’ve reached the 1870s. This rhetorical device underscores the close connection between nature and culture and the ways in which humans are parts of natural systems rather than conquerors of them: As the United States was developing, the tree was developing, too, indifferent to human projects. Finally, the comparison of the slow growth of the tree with the dizzying pace of change in the modern era gives a greater sense of urgency to the call for conservation to protect the nature that is left.