Florida's Amazing Mangroves

Florida’s Coastal Zones

There are 1,350 miles of coastline in Florida and much of the state's distinctive character lies in the beauty of its coastline. So it’s not surprising that more than 75% of Florida’s population lives in or near these coastal zones. 

Waves, currents, and tides are the main agents that shape shorelines, although wind is another major factor once the sand is above sea level. There are both high-energy and low-energy coastal areas in Florida:
- High-energy coasts are usually adjacent to the Atlantic Ocean or the Gulf of Mexico and have strong wave action that suspends and exports fine particles and leaves behind only larger, coarser particles, forming sandy beaches.
- Low-energy coasts are protected by land or plants in estuaries or bays so that they have less natural wave energy allowing the persistence of organisms such as seagrasses, salt marsh plants, oysters, and mangroves. 

Both salt marshes and mangrove forests provide critical habitat for a wide variety of marine & terrestrial wildlife, protect coastal areas from storm surges, build up peat-like soil that sequesters carbon for the long term, and keep up with sea level rise. Salt marshes dominate North Florida coastal zones (and continue much further north), while mangroves are more common in South & Central Florida coastal zones and are the topic of this article.

This mangrove poster by the Wildlife Conservation Society shows just some of the many services that mangroves provide. Read on for more details...

Tulips & Florida: my story

Tulips in Victoria, B.C. in front of the Empress Hotel

I have always loved tulips!

Tulips (Tulipa spp), spring-blooming perennials that grow from bulbs, are in the lily family, Liliaceae. There are about 75 species, but thousands of cultivars. 

Their showy flowers have what looks like 6 petals, but the inside 3 are true petals and the outside 3 are sepals, but since they look the same, they are called tepals. Quite often they have a different colored blotch at the base of the tepals. The standard tulip colors are solid, but a virus causes splotching and variegation and these “broken tulips” are highly valued.

Tulips are native to much of the Near East and Central Asia, the Persian and Turkish people were the first to cultivate tulips. They were introduced to Europe in the 16th Century as the Ottoman Empire spread and then became associated with the Netherlands, which became the major producer for world markets.

Dioecious vs Monoecious plants & more

Seed-producing plants use sexual reproduction to produce their seeds and are divided into two main groups:
- Angiosperms, the true flowering plants with enclosed ovaries where the seeds are housed in a fruit.
- Gymnosperms, with naked seeds usually housed in cones or cone-like structures.

Seed plant reproductive configurations, but many people combine homoecious (self-fertile or perfect flowers) with monoecious since each plant has both male & female flowers or flower parts.  

There are 3 arrangements or configurations of these sexual organs:
1) Dioecious where the male and female structures are housed on separate plants. The main advantage to this arrangement is that cross pollination is forced, so there is more genetic diversity, which allows the plants with the best characteristics to adapt to a changing environment. The disadvantages are that only half of the plants produce seeds and the spread into to new territories is slowed because both male & female plants must be within breeding range.
2) Monoecious where male and female structures are separate, but on the same plant. The advantage is that the male and female structures are close, but pollination still needs to take place and more cross-pollination may occur. Examples include the squash family (Cucurbitaceae) with separate male & female flowers and some grasses like corn (Zea mays) with their male flowers at the top of the plant and the female flowers tucked into leaf notches that become the ears.
3) Homoecious, hermaphroditic or self-fertile where male and female parts are housed in the same structure. For Angiosperms, this would be a "perfect flower." The advantage is that pollination is much more likely, but one disadvantage is that self-fertilization is likely, which causes less genetic diversity. Some hermaphroditic plants have adapted so they cannot fertilize themselves. The vast majority of angiosperm flowers are perfect. 

Dioecious derives from Greek meaning two houses, and as you can probably guess, monoecious means one house. Homoecious is self or the same house.

Epiphytes: Air Plants & More

Ball moss is a common epiphyte & is typical
of what most people imagine when they
think "air plant." It attaches itself to a tree
& spends its life there.
 

Epiphyte derives from Greek epi- 'upon' and phyton 'plant'. An epiphyte is a non-parasitic, organism that grows on a plant and that derives moisture & nutrition from its surrounding ecosystem. Most people associate this with the terrestrial epiphytes or "air plants" that make their living without touching the ground, but wait, there's more...

Terrestrial epiphytes

Terrestrial epiphytes are plentiful where there is frequent rain or fog such as rain forests (both tropical and temperate) and also areas like Florida, especially near wetlands, but some epiphytes are also found in drier areas. They could be vascular flowering plants such as orchids, cacti, or bromeliads including ball moss & Spanish moss. They include vascular spore-producing plants such as ferns. Almost 10% of vascular plants are epiphytic.  Non-vascular, spore-producing plants such as mosses and club mosses are frequently epiphytes. 

Since epiphytic life can be precarious, many of these plants have fine hairs or waxy surfaces to trap or keep water. Some collect water in-between their leaves, but others have adapted to water shortages by using the CAM or C4 method of photosynthesis that can take place even when all their stomata (leaf pores) are closed to conserve water.

Lichens, which are not plants, but 3-way symbiotic organisms (fungi, algae, & bacteria), are also epiphytes when attached to plants. 

Strangler figs (Ficus spp.) are a special case: they are hemi-epiphytes when they begin life as a epiphyte high in the canopy, but when their aerial roots reach the ground, they are no longer epiphytes. It's a clever strategy, especially in rain forests where there is low light on the ground and the canopy is crowded. It's in the light when its young and it often takes over its host's spot in the canopy after strangling it by wrapping its roots around it.
(See below for more on terrestrial epiphytes.)

These barnacles, sessile animals (crustaceans),
attached to a kelp stipe (stem above the holdfast),
are marine epiphytes. 

Marine epiphytes

In the marine environment, plants, such as non-vascular seaweeds and vascular, flowering seagrasses, provide surfaces where sessile organisms can settle. Marine epiphytes include algae (micro & macro), bacteria, sponges, bryozoans, ascidians, protozoa, hydroids, crustaceans, & mollusks. They make their living from the nutrients and oxygen from the surrounding water, not from the plants. Sometimes, when there are too many epiphytes, the host plant may suffer from lack of light or lack of its own gas exchange.

Perennial Peanut is not "Florida-Friendly"

In general, I agree with the "9 Florida-Friendly Principles: 1) Right Plant, Right Place; 2) Water Efficiently; 3) Fertilize Appropriately; 4) Mulch; 5) Attract Wildlife; 6) Manage Yard Pests Responsibly; 7) Recycle; 8) Reduce Storm Water Runoff; and 9) Protect the Waterfront. The overall goal is to reduce nonpoint source pollution through proper fertilization, irrigation, and pesticide use on residential and commercial landscapes."

BUT, over the years I have been critical of the "Florida-Friendly" plant list since only about half of the named plants are actually native to Florida. As a botanist and naturalist, I think that the percentage of Florida natives should be 75% or higher. In most cases, though, the non-native plants are "okay" even though they don't support native pollinators or native birds as well as natives do. 

One exception, in my opinion, is the very aggressive perennial peanut or grassnut (Arachis glabrata), which is in the bean family (Fabaceae) and like other members of this family they fix nitrogen* with the aid of their symbiotic Rhizobium bacteria, so they can grow well in poor soil. 

Coonties: Florida's only native cycad & only Atala butterfly host plant

Coontie is a popular native for parking lots
like this hospital lot in Jacksonville, because it
doesn't need trimming to maintain this height.

Coontie (Zamia integrifolia), a beautiful & unique plant native to most of Florida & some Caribbean islands, has an interesting history of over exploitation & the near extinction of the Atala butterfly (Eumaeus atala) that depends on this plant as its larval food source. Today, coontie is widely planted in all of Florida because it's attractive, drought-tolerant, salt-spray tolerant, plus it grows in poor soil & does not need trimming. 

Coontie is a Cycad

Cycads are ancient plants that have a fossil record that shows that they have not changed much in the last 68 million years. They are gymnosperms, which means naked seed. (Pines are also gymnosperms.) Angiosperms, the flowering plants with their enclosed ovaries and their pollinators such as bees & butterflies developed much later. 

Cycads bear pollen and ovaries in fleshy cone-like structures at ground level on separate male and female plants. They are pollinated by beetles and the coonties use heat in the cones at different times to attract the beetles to the male cones and then to travel to the heat in the female cones. This is called thermogenesis.

Soil: We Need to Stop Treating it Like Dirt

Gardeners can improve their soil.

Why is soil important for gardeners?

We’ve all heard about growing the right plants in the right places so they’ll survive, but without healthy soil, your plants (even the right plants) will suffer or even die. So let’s look at what’s under our feet.

 (This article is an updated version of one I wrote for a garden blog several years ago, which is no longer available online.)

Healthy soil ecosystems are a complex interaction
 between bacteria, fungi, insects, & more.

Soil: the ecosystem beneath our feet

Soil found in native habitats is a complex ecosystem of bacteria, fungi, nematodes, earthworms, ants, salamanders, toads, insect larvae, moles, and more, all living in a substrate of minerals and humus. The minerals are a mixture of rocks, sand, silt, and/or clay. The humus or organic matter consists of fully or partially digested plant and animal parts. As humus is broken down into simple compounds, it provides a living for the decomposers, and eventually yields nutrients for plants. 

One gram (about 1/5 teaspoon) of healthy, non-poisoned soil could contain one hundred million bacteria, one million actinomycetes (a filamentous bacteria), and one hundred thousand fungi; if strung together, their filaments or hyphae would measure about 16 feet (5 meters) in length. This same gram of soil could also contain hundreds of nematodes living on the damp surfaces of the soil particles and maybe a few insect eggs or larvae and some earthworm cocoons. The exact proportions of each of these organisms will depend on soil conditions such as moisture, acidity, aeration, amount of humus, and the local plant community growing in the soil. 

A Quest for a Perfect Lawn: a Case Study

This graphic makes the point about how
out-of-step people are for trying to
maintain unnatural&unsustainable lawns.

To celebrate Earth Day, this post is about rethinking the "perfect" lawns, which are maintained with applications of fungicides, insecticides, herbicides, synthetic fertilizers, and never allowed to go into seasonal dormancy. In Florida winter-dormant grasses are over-seeded with cool-weather grasses, irrigated through the dry season, & fertilized. 

Today's lawn expectations go way back to how European formal gardens & lawns around castles and manor houses were kept to show others how wealthy the owners were.

Today, lawn-"care" organizations can make lots of money by encouraging homeowners to have "perfect" lawns, but does it make sense or cents? As a botanist, naturalist, and a sustainable gardener, I would say, "NO!" 

There are so many reasons for replacing most of your lawn acreage with unpoisoned native habitat & pollinator gardens and then freeing the remainder of your lawn from all pesticides & synthetic fertilizers, mowing it less often at the highest setting, letting it go dormant in the winter & allow a variety of plants that tolerate mowing to grow there.

Measuring Climate Change

Figure 1: Weather balloon with
parachute and radiosonde.

Q: Do you believe in global warming?
A: We are Measuring it.

Guest blog post by Dr. Charlie Paxton, meterologist

We meteorologists have surface temperature measurements all over the world and with continued automation more measurements are being taken as time goes on. We must also consider what is happening above the ground. Weather balloons carry instruments called radiosondes that report temperature, moisture, wind, and pressure as they ascend into the stratosphere. Satellites, both geostationary and polar orbiting, provide a wealth of atmospheric information including global sea level measurements.

The Birds are NOT OK

What is the birds-eye view of your yard
your community?

Birds Aren’t Just Declining.
They’re Declining Faster!

Scientists studying data collected for more than three decades found accelerating losses. The steepest losses in the study, from 1987 to 2021, were seen in Florida, Texas, Louisiana and Arizona. This research offers clues about the causes. Here are links to a gift article in the NY Times that looks at this research and to a WashingtonPost gift article, which both cite the same study.

This research showed a correlation with increased use of pesticides in agricultural regions, but it also linked back to an older study showing that cats cause huge harm to our birds. I wrote about that as well and how controversial this is in this article.

This Red-shouldered Hawk provided its
opinion on how humans treat birds.

BUT...

Whatever the causes for their decline, we are NOT helpless and, as Joan Baez stated, "Action is the antidote to despair."

There are many actions we can take to make our yards and our communities more bird friendly. I've covered this topic from several different angles over the years, so I've gathered some of the most relevant articles here to make it easier for people to up their game at this critical time. The birds need us to act now more than ever.