"The unvarnished truth is that a trained dog is a perishable commodity. Few things are so subject to deterioration. It is almost as hard—and it takes almost as good a hunter—to keep a dog good as to make one as good. Eternal vigilance is the price of a good bird dog, regardless of who you are, or where and how virtuously you live."
"I Went to See a Man About a Dog"
Tales of Quails and Such, 1951