The Everglades National
FIU IDH 4007
Welcome to the Sunschinus State?
Journal Entry #1
Our first fieldtrip in the new semester lead us back to Anhinga Trail. It was much more crowded in the dry season, with wildlife as well as tourists. The animals need water, and the people get to watch them. A recent cold snap had killed many of the exotic cichlid fish, and numerous birds were enjoying the unexpected feast. Afterwards, we went to the Hole-in-the-Doughnut, where an exotic of another kind can be found, and it is not nearly as easily killed as the cichlids.
Brazilian-pepper (Schinus terebinthifolius), which is also known as Florida-holly even though it is neither from Florida nor a holly, grows there in abundance. This shrub or tree is one of the worst exotic pests that outcompete the native flora. It is a member of the Anacardiaceae family, which makes it a relative of poison ivy and poisonwood. The plant grows up to 13m tall and usually becomes a tangled mass with multiple trunks and branches that crisscross each other. The leaves are pinnate with 3 to 11 leaflets; their margins are sometimes toothed. Although clusters of white flowers can be observed year-round, the most intense flowering season is from September to November, and around Christmas time the shrub usually displays copious amounts of bright red berries.
The plant originally came from the coast of tropical Brazil. There, in addition to growing naturally, it is cultivated as an ornamental, a shade tree, or as a trimmed hedge. Its wood is used in construction or for stakes and posts, and twigs are made into toothpicks. A resinous extract from the bark is used to preserve fishing lines and nets, and decoctions from crushed leaves or bark are taken to relieve ailments from bronchitis to rheumatism.
Contrary to all these medicinal uses stand the facts that many people report respiratory problems when Brazilian-pepper is in bloom, and that its sap or prolonged contact with the wood can cause severe itching, rashes, or even lesions. In Florida, some domestic animals develop severe colicks after eating leaves or fruits, and while robins are crucial in spreading the seeds by eating the berries, several other bird species can die from eating too many of the fruits.
Because it is so widespread here, I had always assumed Brazilian-pepper has been growing in our area for quite some time. However, quite the opposite is the case. The first seeds were given to the USDA by plant explorer Walter T. Swingle in 1898, a mere hundred years ago! The plant was deemed to be well suited as an ornamental, and some seeds or seedlings were given to the Plant Introduction Station in Miami to be further distributed.
While the local people were not too eager about the new plant, plant lover Dr. George Stone made Brazilian-pepper popular along the west coast in the late 1920's. As late as 1944, Dr. Henry Nehrling wrote in Volume I of My Garden in Florida: [Stone] distributed these seedlings freely among his friends and plant lovers, and many were planted out along the city streets. While strolling along one of these thoroughfares the writer was struck by the unique beauty of a fine specimen in full fruit. He collected quite a number of the berries, from which all the specimens in his Naples garden have sprung ... It ought to be in every garden in Florida (qtd. in Morton, 1978, p. 354).
Mr. Nehrling certainly got his wish granted, although it is questionable whether he would actually be happy about it today. Not only did the plant lovers notice that Brazilian-pepper rather quickly outgrows its allotted space and turns into a dense tangle, it has been established that it emits chemicals that inhibit the growth of other plants (Mahendra et al. 1995). Combined with this comes an adaptability that has made the plant present in many habitats in South and Central Florida. On a global scale, it has spread to other parts of Central and South America, the Bahamas, the West Indies, North and South Africa, southern Asia, Mediterranean Europe, and several US states (Langeland & Craddock Burks 1998, p. 55).
The Hole-In-The-Doughnut project is one of the largest attempts by an agency to remove this invasive species. The "Hole" itself was an agricultural area before the Everglades National Park (ENP) was established. Since fertilization and rock plowing had increased the nutrient contents of the fields, they became highly suitable to exotic pest plant invasion while native plants, which prefer lower nutrient levels, would no longer grow there. After the park take-over the fields were left fallow, and within a few decades a dense Brazilian-pepper thicket had developed. Any native plants that "ventured" into it faced some stiff competition for sunlight and stood very little chance to reclaim the land.
This was a major concern for park biologists since such a large area represented an enormous seed source to further spread the Brazilian-pepper into nearby surroundings. Through a few studies, it was established that the best way to eradicate the plants is to remove them and the soil in which they grow, because even when the plant is killed, the seeds remaining in the soil are certain to sprout right back. Thus, the shrubs are first felled and mulched by machines, then the soil is piled into large mounds, and finally the rock is scraped. This bare rock is then left to itself, and almost miraculously the native flora returns on its own. I was delighted to see how much variety there was in a plot that had been covered by a closed canopy of Brazilian-pepper only seven months ago, and now not a single Schinus plant could be found.
While this method seems to work, it is quite intrusive, and I don't know whether it can be utilized in all habitats. However, while doing research for this paper, I also came across a website that describes a wasp species called Megastigmus transvaalensis, which feeds on the drupes of Brazilian-pepper. The insect probably came to Florida about ten years ago from Reunion or Mauritius via France in Brazilian-pepper fruits sold as spices in exotic food stores. So far, the berries have been found to be its only host in Florida, and the wasp effectively destroys between one and three quarters of the fruits so they can no longer germinate.
Although change is an integral part of Nature, our interference has already grossly distorted it from its original form. I strongly doubt that Brazilian-pepper would be in all the places it can be found if it were not for our worldwide trade. While this plant might have its benefits and uses, I personally prefer the diverse habitats we have not tried to improve or decorate yet. Thus I hope that some of our well-meaning efforts will actually preserve what is left of these areas.
K. A. Langeland, K Craddock Burks. 1998. Identification & Biology of Non-Native
Plants in Florida's Natural Areas. University Press of Florida. 164 p.
Mahendra KJ et al. 1995. Specific competitive inhibitor of secreted phospholipase
A2 from berries of Schinus terebithifolius.
Phytochemistry 39:537-47 Morton JF. 1978. Brazilian pepper,its impact on
people, animals and the environment. Econ. Bot. 32:353-59
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