Fall means pears, and Saveur just posted a great guide to the most common varieties, accompanied (of course) by some lovely photos.
As Russ Parsons describes elsewhere (specifically, in his great book How to Pick a Peach), the first sign of pear season are “Bartletts, or summer, pears, and although they are the first fruit on the market, they are rarely the best.” For other varieties, including what to expect from an Anjou versus a Bosc versus a Comice, head to the Saveur tasting notes and, if you feel like hitting the kitchen, their favorite pear recipes.
Also, check out this post from the Oregon State University Extension on when to pick a pear from its tree and how to tell when it’s ready to eat. They’ve got some nice science-y stuff in the post, along with practical advice like the following:
How do you tell when a pear is ripened to perfection? “Hold the pear gently but firmly in the palm of your hand, as a baseball pitcher might hold the ball while studying signs from the catcher,” recommended [botany professor David] Sugar. “Apply the thumb of that same hand to the pear flesh just below the point where the stem joins the fruit. When the flesh beneath your thumb yields evenly to gentle pressure, it is time to eat your pear. If you have to push more than slightly, it is not ready yet.”
Finally, if you find yourself wanting to store pears past the end of the season, check out this nice info sheet (PDF) from Utah State University Extension on freezing and canning pears.