Maritime forests develop under the influence of salt spray on barrier islands and near estuaries. Historically, maritime forests based on the climate in each area rimmed our coasts. Today, few examples remain as a result of coastal development.
What remains of the maritime forest on Amelia Island is part of the southeastern maritime forest that once extended from southern Virginia to Florida. More specifically, based on geomorphology, it is part of the Georgia Embayment, which extends from Cape Romain, SC, down through the Talbot Islands.
What types of trees are native to our maritime forest?
The maritime forest in our area is typically characterized by a high canopy of Live Oak and an understory dominated by Saw Palmetto. Other than these plants, the most common canopy trees in our Amelia Island maritime forest include Laurel Oak, Water Oak, Sabal (Cabbage) Palm, Hickory, Southern Magnolia, Red Cedar and several types of Pine. In areas that are more sheltered from salt spray, Red Maple and Hackberry are quite common. The understory includes: Wax Myrtle, American Holly, Yaupon Holly, Dahoon Holly, Sparkleberry and Beautyberry. The environment created by these trees requires a long time to develop.
“The maritime forest can be distinguished from the shrub forest by its clearly defined canopy. This high canopy shades out many of the shrub forest plants. Some plants are able to survive in this low light environment and make up the understory of the forest. The soil in the forest is very moist and fertile to support these large trees. It may take up to a century for these types of soil conditions to develop.” – A Guide to a Georgia Barrier Island, 1996
How does the environment shape the forest?
Salt is the primary factor determining what can and can’t survive in a maritime forest. The salt spray (“salt aerosol”) burns the leaves of the plants. For example, Live Oak has a high tolerance for salt; however, the salt burns the young leaves as they emerge above the canopy. This gives the tops of the trees the appearance of being pruned and prompts the limbs to grow horizontally, rather than vertically. Another factor that shapes the maritime forest is the periodic overwash of salt water from storms. Those trees and understory plants living near the ocean have a higher salt tolerance than those just beyond the reach of most salt spray.
Wind also shapes the maritime forest trees. We can actually identify the predominant direction of the wind by looking at the trees. Smaller trees and shrubs along the edge of the forest closest to the ocean and along the ocean-facing side of openings in the canopy demonstrate how the smaller growth helps to direct the winds up over the taller trees so that they are not damaged by wind and salt.
Sand is constantly on the move and is limited in nutrients, so this influences the formation of the forest until soil can be developed.