The Maryland Zoo in Baltimore has more than polar bears and prairie dogs to show its visitors. Just look up!

In addition to some 1,500 animals on exhibit, the lush 135-acre compound in Druid Hill Park boasts some champion trees, such as the number one osage orange in Baltmore city, seen at right.   This giant is 76 feet tall, with a trunk that's 20 feet 1 inch around.

There's also a state champion bur oak in the African exhibit, measuring 87 feet in height and 11 feet 4 inches circumference.  Plus another city champion, a white ash, and two finalists, a towering 148-foot tulip poplar and a white oak.

The trees earned their champion or near-champion status under the state's Big Tree Program, which measures trees all over Maryland and seeks to identify and preserve the biggest and most magnificent of them - most in people's "backyards."

Though its primary focus remains on its wildlife, the zoo's decided to shine a bit of a spotlight on its arboreal splendor.  It's posting informational signs by these and some other notable trees on the grounds.  Sheryl Heydt, the zoo's curator of horticulture, is holding the osage orange sign in the picture at left. 

Other trees of interest include a Turkish filbert, which Heydt says she's been told are very rare in these parts, a sapling from the Wye oak, the venerable tree destroyed by a storm in 2002, and a beech that's showing its age - with the date 1907 carved in its trunk. Such graffiti is prohibited today, but it's a reminder that the Maryland Zoo in Baltimore is the third oldest in the country, established in 1876.  Only Philadelphia (1873) and Cincinnati (1874) have older zoos.

So stop by and check out the zoo's trees in addition to its animals. For those who want a more in-depth exposure, there's a tree identification walk on Monday, Oct. 10, where visitors can stroll through the grounds and learn to spot them by their leaf, bark, twig, and fruit characteristics.  The session is for early risers, from 8 a.m. to 10 a.m. It's free to zoo members, and registration is required. More here.

(Photo at top of osage orange courtesy Maryland Zoo in Baltimore)