KEY LARGO -- When one imagines a champion tree, California's 350-foot sequoia redwoods or Colorado's 4,000-year-old bristlecone pines probably come to mind.

But, according to the National Register of Big Trees, Monroe County is home to 32 national champion trees, and 20 are on the island of Key Largo. Most, however, don't stand out in a crowd.

The reason, of course, is our unique climate. Trees such as the roughbark lignumvitae, soldierwood and the red stopper are tropical trees that have found a foothold in the subtropical climate of the Florida Keys. Though some are no taller than 40 feet, the local champions are the biggest of their species in the United States.

The National Register of Big Trees measures trees by their circumference at 4.5 feet above the ground, by the vertical height of the tree to the nearest foot and by the average diameter of the crown to the nearest foot.

One Keys champ is a red stopper located in the Crocodile Lake National Wildlife Refuge in North Key Largo.

"There is a stand of red stopper in the refuge that covers about a quarter-acre," says Steve Klett, refuge manager. "They look like pigeon plum but the leaves are much smaller. You look back there and it's hard to imagine that there's a champion there, but they are slow-growing trees. It takes them a long time to grow very big. You look at them and say 'big deal."

But to arborists and naturalists, they are a big deal.

Whit Bronaugh, in an article titled, "Land of the Little Giants," calls Key Largo a hot spot for champion trees.

"The Florida Keys have more species of native trees -- about 110 -- than any other location north of Mexico. ... In fact, only 11 states have more title holders than [Key Largo], which covers less than 30 square miles."

Last week, long-time John Pennekamp Coral Reef State Park Ranger Joseph Nemec and Lt. Bob Bodner visited some of the local champion trees in the hardwood hammocks of Pennekamp and Dagny Johnson Key Largo Botanical State Park along County Road 905.

Nemec has been responsible for finding and registering the champions in the two parks over the past dozen years.

"All 20 trees on the register I found and submitted," said Nemec.

He and Bodner said when they find a tree they think may be a champion, they measure it and submit the data to the National Register.

"They then send someone -- an arborist, I believe -- to measure the tree and determine if it really is a champ," Bodner said.

"Some of these champions don't get very big, but that's the beauty of it, you can have a tree this big around and it's a champion," he said, joining his fingers and thumbs together to form a small circle.

At Dagny Johnson park, a champion soldierwood turns out to be an inconspicuous tree nestled in with other vegetation along a trail. When the tree's seed pod opens to expel seeds it makes a sound like a pop gun.

Key West is home to a champion satinwood tree, which Carolann Sharkey, executive director of the Key West Botanical Gardens Society, describes as a "very rare tree."

"It has grown to 30 feet high, has a 35.5-foot crown and is 95 inches in girth," she said.

A potential state champion saffron plum tree is also located at the Botanical Gardens site on College Road, Stock Island, Sharkey said. She expects it to be confirmed a champion by the Oct. 1 deadline for submitting candidates.

National champion trees are measured every 10 years to update the register.

"The reason for that is these trees grow and need to be upgraded," said Bodner. "Some die from storms such as hurricanes and lightning strikes, insect infestation or they have lived out their life spans."

That is why the National Register lists several dozen types of tree as "Species Without Champs."

On that list are several trees Nemec recognizes as being found in one or the other of the parks, such as longleaf blolly, willow bustic, torchwood, wild-dilly, joewood, maidenbrush, milkbark, paradise-tree and seven-year apple.

Those who think they may have a potential champion tree in their neighborhood can view a revised list of national champion trees on the American Forest web site, www.americanforests.org/resources/bigtrees.

Who knows which yard may contain the next champ?

sgibbs@keysnews.com