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EVERGLADES
National Park
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PLANT-AND-ANIMAL COMMUNITIES (continued)

Willow Head

Willows pioneer new territories and create an environment that enables other plants to gain a foothold. Their windblown seeds usually root in sunny land opened by fire and agriculture. Since these trees require a great quantity of water, the solution holes in the glades are favorable sites. Seedlings grow, leaves fall, and stems and twigs die and drop—contributing to the formation of peat. When this builds up close to or above the surface of the water, it provides a habitat for other trees such as sweet bay and cocoplum; with enough of these the willow head changes character and becomes a bayhead.


WILLOW HEAD. Willow head with alligator holes typically have a doughnut shape—the gator hole representing the hole in the doughnut. (click on image for an enlargement in a new window)

Years ago, when alligators were plentiful, they weeded the willow-bordered solution holes, keeping them open. Consequently, the willow heads were typically donut-shaped. Today, however, alligators are scarce and many of the willow heads have no gators. The solution holes fill with muck and peat; relatively tall willows rise out of the deep, peat-filled centers, with increasingly smaller ones toward the less fertile edges, and the willow heads take on the characteristic dome-shaped profile but not nearly the height of the cypress domes. They have a clumpy, brushy appearance, seeming to grow right out of the marsh without trunks.


POMACEA SNAIL. The sole food of the everglade kite.

Willow heads that do have alligator holes have a seasonal concentration of aquatic animals and the birds and mammals that prey upon them. They rarely support orchids or bromeliads, for the bark of the southern willow is too smooth to provide anchorage for the seedlings of these plants.

During drought periods willow heads, like bayheads, are vulnerable to the fires that sometimes burn over the glades.


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Last Modified: Sat, Nov 4 2006 10:00:00 pm PST
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