Rosemary Ridge Trail
Trails within the Arboretum are graded easiest, moderate, and more difficult based on terrain and length.
Trail Grade: More Difficult
This is a one-mile, winding dirt trail that crosses multiple habitats: a xeric hammock, a rosemary/oak scrub, a depression marsh and a wetland marsh, among others. There is a small, gated access trail to the Rosemary Scrub which is soft sand. No dogs are permitted on the Rosemary Scrub Trail. The deer moss is very fragile, so please avoid disturbing it. This trail connects to the Live Oak Trail via a boardwalk over a small stream.
Points of Interest
Mixed Hardwood Forest
The mixed hardwood forest community covers about 40 percent of the Arboretum. This community is found in low elevations and represents a transition zone between the drier upland areas (including xeric hammock and upland forest) and seasonally-flooded areas bordering Jones Creek. Mixed hardwood forest soil is generally very acidic and moist. Trees in the mixed hardwood forest are generally taller than the trees in the neighboring xeric hammock and the forest floor of the bottomland forest has many fern species, but few grasses. Canopy trees include the water oak (Quercus nigra), the diamond-leaf oak (Quercus laurifolia) and bald cypress (Taxodium distichum). The bald cypress is a tall tree that can grow in anoxic (low in oxygen) soils and in Jones Creek because of its special roots or knees. These knees rise out of the ground to help anchor and provide oxygen to the tree. The mid-story layer consists of shrubs, short trees, and saplings that will grow in the moist shade, such as the wax myrtle (Myrica cerifera) and swamp dogwood (Cornus foemina). The wax myrtle is characterized by its irregular-shaped leaves and pleasant aroma of its crushed leaves. This tree was used by the Timucua to ward off mosquitoes. The swamp dogwood is an important food source for many birds and is the larval host of the Spring Azure butterfly. The dense overstory of the forest provides filtered light and allows for little evaporation, which creates dappled moist conditions that are perfect for ferns and herbaceous plants. The cinnamon fern (Osmunda cinnamomea) has tall fertile fronds with spores that appear to be cinnamon-colored. The never-wet(Orontium aquaticum) which grows along the banks of the creeks, has a waxy outer layer on its leaves that causes water to bead.
The Live Oak and Rosemary Ridge Trails wind their way through xeric hammock. This habitat covers approximately 30 percent of the Arboretum and was likely much smaller a century ago when fire and fire-tolerant pine habitats, such as scrubby flatwoods and sandhills, were more prevalent in this area. Xeric Hammock only develops in areas that have been protected from fire for at least 30 years. As you walk along the trails through Xeric Hammock, you will find a thriving community of plants in the canopy, mid-story, and understory. This community grows in well-drained, sandy soils. Little water and nutrients are retained in the sandy soil, resulting an abundance of palmettos, low-growing oaks and drought-resistant shrubs. The canopy is dominated by stunted laurel (Quercus laurifolia) and live (Quercus virginiana) oaks and an occasional chapman’s oak (Quercus chapmanii). The mid- and understory layers are dominated by palmettos and shrubs in the blueberry family such as sparkleberry (Vaccinium arboretum), rusty lyonia (Lyonia ferruginea), and fetterbush (Lyonia lucida).
Lichen species abound in Xeric Hammock community. Reindeer moss (Cladonia rangiferina), named for its food source to caribou and reindeer in the north, is actually lichen which is composed of an alga and fungus in a symbiotic relationship. It forms a dense, pillow-like colony on the ground. Reindeer moss is very sensitive to trampling. If you encounter reindeer moss, please don’t disturb it as it is slow to recover. Other lichen you may see when walking on the Live Oak trail is Christmas lichen (Cryptothecia rubrocincta). Its name comes from the red and green colors seen on the sides of trees. This lichen is normally found on trees in areas of open sunlight.
Tidal Marsh Area
The northeastern portion of the Arboretum is bounded on the east by Jones Creek. This Creek flows northward through the Arboretum and into Mill Cove and the St. Johns River. The lower reaches of Jones Creek are tidal, resulting in about a 3 ½-foot change in water level twice every 24 hours. The timing of the tides changes with the moon cycles. Tides times are approximately 50 minutes later each day. For example, if high tide one day is at noon, the next day high tide will be at 12:50 p.m. Looking out across the tidal marsh, you will see two different types of vegetation. Black needle rush (Juncus roemarianus) typically grows closer to the shoreline and is darker in color. Smooth cordgrass (Spartina alterniflora) grows in the wetter areas closer to the creek and is typically lighter green in color. In the late fall and winter, these two grasses create a beautiful mosaic of greens, tans and browns. Notice the changes in color and patterns of these grasses as the seasons change. Many other plants also grow in these tidal zones. Estuarine tidal marshes are extremely valuable as they are the breeding ground for many saltwater fish, crabs and shrimp.
Rosemary Scrub Gated Access
Native rosemary (Conradina spp.) is found along the Rosemary Scrub Trail. This plant, a relative of the common rosemary used in cooking, is very drought tolerant and thus able to grow in the sandy, nutrient-poor soils of the rosemary/oak scrub. The plant has adapted to the harsh, dry environment by developing chemicals that inhibit the growth of other plants nearby. This inhibition minimizes competition from other plants for scarce resources. It also repels plant eaters. The dry sandy scrub is extremely attractive to developers, and as a result, the Florida Rosemary Scrub is one of the most endangered ecosystems in the world. Many of the species in this small area, including the Florida rosemary, are listed by state and federal agencies as endangered, or threatened, plants. Enjoy looking at the rosemary, deer lichen, and other unusual plants in this area, but please do not disturb them and stay within the trail’s boundaries.
Seasonal Pond / Depression Marsh
This saucer-shaped depression alternates between a shallow lake during wet periods and a dry grassy bowl during dry periods. The vegetation in seasonal ponds typically grows in concentric rings. These rings can be correlated to the wetness of each zone. The predominant plant species in this feature is red root (Lachnanthes caroliniana), which indicates that the marsh was destroyed recently, probably by the mining in the mid-20th century. Observe that a variety of forbs and grasses are returning to different portions of this seasonal pond. Within a hundred years or so, this marsh should recover.