Rosemary scrub

A walk along the Florida Trail in Chuluota Wilderness reminded me of the delights of Florida’s scrub, and why – especially in winter – it’s such a fascinating place to take a hike. Scrub is Florida’s own desert, the tops of ancient sand dunes where water can’t collect, sand as bright as freshly fallen snow. Its trees adapted to a lack of water. Myrtle oak, scrub oak, and Chapman’s oak form forests in miniature, a low canopy of dense lilliputian thickets that Florida scrub-jays love. Here and there you’ll see scrub holly and scrub plum, recognizable from their leaf shapes but distinctly small compared to their full-sized cousins.

In an oak scrub, sand live oaks shade out the others, creating a higher canopy where twisted branches of rusty lyonia (also known as crookedwood) add texture to the mix and puffy lichens like deer moss and British soldiers thrive. A sand pine scrub has sand pines, with soft short needles and tightly closed pine cones, forming a high canopy above.

And then there is the rosemary scrub, the rarest scrub of all. These domed, rounded shrubs, some up to ten feet tall, emit a distinctive aromatic odor, reminiscent of sagebrush. But they are not the rosemary herb used for cooking. They grow atop bald patches of sugary white sand, sometimes in a wide open space, sometimes under a loose canopy of sand live oaks or sand pines. Like sand pines, they are fire-dependent; scrub requires fire to rejuvenate. Florida rosemary releases a natural herbicide into the sand to inhibit the growth of other plants near it, including its own seedlings, which is why they generally look so evenly spaced on the forest floor. When fire sweeps through the scrub, it destroys the herbicide, allowing new growth to take root.

Around rosemary scrub, you’ll always see lichens. Deer moss – the puffy white-to-seafoam colored lichens seen so commonly in Florida scrub – are in the Cladina family and come in several shapes and colors. A soaking rain or morning dew makes them spongy, but they eventually dry out and become brittle as the sun strips the scrub of its moisture. Years ago, I was on a field trip with the Florida Native Plant Society when our leader poured a little water out of his water bottle onto a crispy-looking silvery lichen, Cladonia prostrata, and we watched it unfold and puff up.

Despite its rarity as a habitat, there are dozens of places to walk in rosemary scrub in Florida, thanks to thoughtful protection of this very unusual habitat. It tops the Lake Wales Ridge, and appears along coastal ridges on both coasts and in the Panhandle. It is downright immersive on a walk through Lyonia Preserve in Deltona. Along the Florida Trail in Chuluota Wilderness, the scrub is a magical place, with a segment of understory dominated by plump rosemary bushes and colorful lichens. It is a habitat worth slowing down for and savoring.