We arrived at the Homestead Entry Gate to Everglades National Park at 6:30 pm on a pitch black, late January evening. As we drove the 38 miles to our lodge accommodations, we noted some small trees just alongside the road that lit up with an eerie, gray glow from the light of the LED headlights – looking almost like apparitions. It was all quite foreboding on the desolate roadway.
The next morning, I was curious to see what type of trees were along Main Park Road that had made our entry the previous night quite spooky. They were light gray trees, ranging from a couple of feet to perhaps 20 feet in height, that did not look quite so mysterious on this dreary, overcast day. After studying them I noted that they had features of mature Bald Cypress, with rounded cones from last season, lichened bark, and buttressed bases. Some even had the start of this year’s male cones. But they were all so short. Bald Cypresses can reach heights of 150 feet. I was perplexed.
Later that day I stopped at the visitor center to ask the park rangers about a unfamiliar palm tree that I was trying to identify, and inquired about the apparent small Bald Cypresses that I had seen. They told me that they were “Dwarf Cypress”. I was only aware of two types of cypress in the Southeastern U.S., the well known Bald Cypress, and Pond Cypress, a cousin of Bald Cypress that is smaller. We went through the remainder of our stay referring to them as Dwarf Cypress. Given the tightness of our schedule on our short stay in the Everglades, I left further study and identification of these trees till I returned home.
For me the question remained whether this was a dwarf version of Bald Cypress or its cousin Pond Cypress, which I had never seen or studied. I knew that Pond Cypresses were somewhat smaller than Bald Cypresses but this size discrepancy was dramatic. The lack of leaves on the trees would also hamper more definitive identification.
Classification of the two cypresses is somewhat controversial with two schools of thought. Some believe that they are two separate species and give them two distinct scientific names: Bald Cypress – Taxodium distichum and Pond Cypress – Taxodium ascendens. Others consider Pond Cypress to be a subspecies of Bald Cypress, with the scientific name Taxodium distichum var. imbricarium. Imbricarium refers to the needles overlapping, or being “imbricate”. To me, there are such obvious differences in the leaves of the two that it would be hard to consider them the same species. The Pond Cypress leaf is scale-like and arranged linearly, along a deciduous twig. The leaves arise spirally off the twig. The Bald Cypress leaves come off horizontally from the deciduous twig, giving the branchlet a feather-like appearance.
Pond Cypress and Bald Cypress leaves – each needle is a single leaf.
Luckily, when we got home we found a few photos of leaves of a dwarf cypress that the photographer had noted along the Pa-hay-okee Overlook Trail. The tree had been recently pruned during boardwalk reconstruction and it appeared to cause premature leafing in this single specimen. One of those photos is above on the left.
So my conclusion is that the Dwarf Cypress of the Everglades are Pond Cypress. Pond Cypress, while smaller than Bald Cypress, are normally not small trees. They are often 50 to 70 feet in height when mature, but specimens to 90 feet have been noted. They usually grow in swamps or along other non-moving bodies of water. By contrast, Bald Cypress can grow to 150 feet and generally grow in areas with moving water, such as riverbanks, streams, and swamps with slow-moving water. Both species can live for over a thousand years.
The Pond Cypresses’ “dwarfness” is a fascinating ecological story. The specimens we saw ranged from a 2 to 20 feet in height and were typically widely scattered.
Despite their small size these dwarfs can be up to 150 years old. Their stunted growth and comparatively short life span is the result of the nutrient poor conditions in which they live. The plains of the Everglades are notable for a plate of subsurface limestone that prevents the trees’ roots from penetrating deeper. There is also very thin, poor soil. Other stressors would be the dry season and wildfires. So the small but aged trees take on the appearance of mature, large specimens, with pronounced buttressing at their base, and a collection of lichens on their bark.
In the afternoon we noted an unnamed boardwalk that went out into a grouping of dwarf Pond Cypress, allowing us to look at them more closely.
We could then better appreciate the wide bases and lichen on the trunks.
One common feature of both Pond and Bald Cypresses are the “knees” that arise off the horizontal roots and extend above the water line. It is thought that they play a role in respiration, and possibly in stabilizing the trees in soft, muddy soils. Perhaps because this area is only submerged during the wet season, these cypresses did not exhibit a lot of knees. Resources sometimes note that the knees of Pond Cypress are less pointy than those of Bald Cypress, but I think that there is enough variation in form for both species that it would not be a reliable identification trait. The arrow in the below photo marks one of the few knees that we saw.
Tree references note that the Pond Cypress’s bark is somewhat grayer than that of the bald cypress and perhaps that is why they had that eerie glow in the headlights at night.
So the mystery of the Dwarf Cypresses is solved and they are another chapter in the fascinating story of the Everglades. After researching this article I am confident that I have probably seen Pond Cypress before on our treks in the Florida Panhandle, but did not take the time to discern the difference in the leaves high up in the canopy. This turned out to be another life long learning adventure with nature. For additional reading I have provided a couple of useful links below.
Photos by Peggy Juengling Burns, with the exception of the Bald Cypress leaves which were noted on the iNaturalist website.
Links:
https://www.floridamuseum.ufl.edu/southflorida/habitats/cypress-swamps/flora-fauna/