The golf ball-size seed pod had lodged in the leafless lilac's branches. A swift bundle of black and white feathers darted out of a nearby tree, landed in the lilac, and deftly picked seeds out of the pod. Each seed was brought back to the tree where it was quickly consumed, and the process started again.

Although it sometimes alit on the seed pod itself, the bird weighed so little that it didn't dislodge the food source. The bird adopted every imaginable stance to get at the seeds while its small black bill probed the inside of the ball for seeds. This Carolina chickadee (Poecile carolinensis) was enjoying seeds that were off-limits to most creatures.

The source of the seeds was a huge sweet gum tree. It is undoubtedly the biggest tree in our yard; a beautiful specimen. The tree rises 100 feet and leafs out into a monumental crown of bright green star-patterned leaves annually. The color display in the fall is terrific, too.

So what's not to like? The sweet gum seed balls, which number in the hundreds if not thousands annually.

It takes a tree 20 years to reach maturity, but then it becomes a prolific seed producer. The 1.5-inch diameter balls are spiky and lie nearly indestructible on the ground for months. They are painful to bare feet, lumpy under shoes, and hard as heck to rake up as they become entangled in the grass.

To the chickadee, though, that accursed spiky ball is a steady source of food until the spring buds and bugs make their appearances.

Like many, I can watch the acrobatic chickadee endlessly. The bird's habit of taking its food to a separate location to consume it means that the bird, which weighs just 0.3 ounces, is in almost constant motion when feeding. As I watched out our living room window, the bird hung upside down, ignoring the dictates of gravity, getting the seeds from underneath the ball.

In the spring, this bird will be just as agile as it clings upside down on tiny branches to get the insects clinging to the underside of leaves. Quite simply, chickadees are a lot of fun to watch.

The Carolina chickadee is a resident species in the southeastern quadrant of the United States. The northern part of its range roughly parallels the Mason Dixon line. Its close cousin, the black-capped chickadee, inhabits the regions north of that line. The two birds look almost identical and often are easiest to tell apart by geography (in New York, think black-capped; in Virginia, think Carolina), or voice. The Carolina chickadee's song and call are both higher pitched and faster than its northern cousin's.

Chickadees have black caps and bibs as well as eyes and bills. A large, white cheek patch extends to the nape. The tail and wings are dark gray with a bit of white, while the underside is pale. The bird often has a buffy patch on its sides. The white wing markings on the Carolina chickadee are muted. Those of the black-capped are more defined, but the difference is subtle and hard to use as a field identifier. In areas where the two ranges overlap, such as southcentral Pennsylvania, the two species will occasionally hybridize. For the most part, though, the birds don't mix.

Carolinas usually pair off for several seasons. The male and female become part of a small flock of eight to 12 birds in the winter, but then set up their own nesting areas in the spring. The birds produce a single brood annually. They use tree holes as nests. Sometimes they will use an abandoned woodpecker nest. Oftentimes, they will excavate their own nest hole. The mother roosts in the nest while the father plays sentinel on a nearby branch every night.

Chickadees eat a diet of both insects and vegetation, including seeds, during the winter (sweet gum seed balls fall from December to April). During the rest of the year, when insects are abundant, chickadees switch over to a diet that heavily favors fauna over flora. Spiders and insects hiding under leaves are no match for these birds, which are adept at catching a meal from any posture.

The momentary pleasure of seeing a Carolina chickadee do its aerial dance slowly stretched into uncounted minutes of enjoyable viewing. The pint-sized chickadee was eating a nutritious meal and the sweet gum, the largest organism in our yard, was having its seeds dispersed.

I found myself benefitting, too. With every seed, the chickadee pecked away at my hardened negative attitude toward those spiky gumballs. The chickadee grew from amusing to impressive the longer I watched. It may weigh just a third of an ounce, but it was playing a big role in our corner of the ecosystem and an equally large role in my psyche.