There is something about ferns that makes them special. With their curled fronds, diverse colors, and shapes, ferns are unlike many other plants. What is it that makes ferns so special?
Short Sum-Up: Ferns, among Earth’s oldest plant families, reproduce via spores, possess adept toxin-filtering abilities, and thrive in diverse environments. They also contributed to fossil fuel formation, served as craft materials for weaving, and are praised for their medicinal value.
Let’s dive into a bit of fern history and knowledge to appreciate the uniqueness of these green fellows that populate vast regions of our planet.
Fern Facts: Unique Traits That Make Ferns Special
The unique traits that ferns come with are plenty. Here is a short overview of what makes ferns special:
- Evolutionary age: Ferns are among the oldest plant families on this planet.
- Second-biggest plant group: More than 10’000 fern species live on Earth today.
- Spores: Ferns reproduce through spores, not through seeds and flowers.
- Filtering capacities: Ferns clean toxins out of the air and the soil.
- Ecological savviness: Ferns evolved to fill a lot of environmental niches.
- Medicinal properties: Indigenous people as well as nowadays scientists appreciate ferns’ medicinal uses.
- Natural gas provider: The fossilized ferns of the Carboniferous age are the major component of today’s fossil fuel deposits.
- Craft resource: Many types of ferns were traditionally used for artisanal crafts such as weaving
Now, it definitely needs some further explanation on all of these facts and how ferns acquired such uniqueness.
Living Fossils: Ferns Are More Than 400 Million Years Old
Ferns are among the oldest plant species on planet Earth. They have evolved through millions of years of a changing planet since the middle Devonian age, with our modern ferns starting to evolve around 65 million years ago. Current fossil findings estimate the first ferns appeared on this planet almost 400 million years ago.
Rest assured that the Devonian age of Planet Earth was not as favorable for today’s living beings as the environment we have now. In the early Devonian age, the land masses were still divided into the two massive continents Gondwana and Euramerica. The atmosphere resembled a huge planetary greenhouse, generally very warm and arid with average ocean temperatures of about 86 °F (30 °C) (Science Direct, Volume 222, 2021).
It was the period in Earth’s history when the first green algae moved from marine to terrestrial environments, and when the growing mass of plants locked so much carbon dioxide in the soil that the planet started cooling down a couple of degrees, enabling plants to grow bigger without overheating.
According to current scientific studies, among the first plants to grow leaves in the late Devonian age were the ancestors of the modern ferns we live with today (American Fern Society).
Even though those ancient fern species from 400 million years ago have all gone extinct until today, our modern ferns are related to them. The fern family has been around since shortly after the beginning of life inhabiting the terrestrial zones with the first algae migrating to land.
Interesting fact: Many of the ancient ferns used to grow tall and big like trees in a forest. Some such tree fern species can still be found today, for example in New Zealand. Walking through a tree fern forest made me feel like I was back in the age of dinosaurs and got me imagining the landscapes of 400 million years ago. There is something very ancient and other-worldly about these plants.
The Weight of Numbers: An Estimated 10-15’000 Fern Species Live on Earth Today
Today’s plant world is dominated by vascular plants. Ferns make up the second-biggest plant group of vascular plants on this planet, right after the group of flowering plants (angiosperms). Given that about 80 % of our world’s plants are vascular plants, and ferns being the second-biggest group among them, we are literally surrounded by ferns.
What are vascular plants? Vascular plants are made up of a xylem and a phloem. Vascular refers to the vessels contained in the plant tissue. The xylem vascular tissue is mainly responsible for transporting water and the phloem vascular tissue for transporting nutrients and sugars within the plant.
These transporting vessels are what differentiates them from non-vascular plants. Non-vascular plants, often collectively referred to as bryophytes, include mosses, liverworts, or hornworts. It is assumed that vascular plants evolved out of earlier non-vascular plants.
There are an estimated 10-15’000 known species of fern today, classified in more than 40 different families. Most fern species today live in tropical or subtropical areas. New species are still being found in unexplored areas, hence the total number of fern species on this planet is assumed to be much higher.
Fossilized Swamps: How Ferns Fuel Your Car
As the American Fern Society states, ferns were growing abundantly in the ancient swamps and forests of the Carboniferous age about 300 million years ago. When these huge ferns as well as any other plants died, they sank into the anoxic swamps at their base and fossilized.
These fossilized swamps are the greatest natural gas and coal deposits on Earth today. So, whenever you are using your car, think of how the ancient ferns are fueling it!
Ecological Opportunists: Why the Fern Species Come in All Shapes, Sizes, and Habitats
Due to their old evolutionary age, ferns come in a varied diversity of shapes, sizes, and morphologies and live in a wide range of habitats. Some ferns do not look at all like what we imagine to be a fern, such as the Kidney Fern (Hymenophyllum nephrophyllum) that is native to New Zealand.
Ferns are diverse and different from any other plants in terms of their habitat, form, and reproductive methods. When the newly evolved flowering plants (angiosperms) rapidly took over the world about 100 million years ago, ferns, with their specific ways of living, were able to successfully exploit the many niches left out by the flowering plants.
Hence, ferns can be considered pro-ecological opportunists, being able to fill the niches and live in even extreme environments successfully.
Reproduction Through Spores: No Flowers on Ferns
As opposed to flowering plants, ferns reproduce by spores which they produce through meiosis (cell division). Ferns do not need seeds, flowers, or pollination to reproduce.
There are other plants using spores, such as mosses, but the reproduction system of ferns is unique in that it has two living stages that are completely independent of each other. The Mother Plant, also called the sporophyte plant, produces spores that fly away in the wind. The ferny plants we see are hence the spore-producing living stage of ferns.
Once the spore lands and starts growing somewhere, this plant life cycle is called the gametophyte. As Racusen describes it, “the fern gametophyte is a small plant that exists as a prolonged intermediate in the fern life cycle, between the germination of a spore and the mature sporophyte” (Ann. Bot., 2002). The gametophyte will transition eventually into another sporophyte plant.
What makes gametophytes of ferns unique is that they can live independently from their sporophyte plant. All other plants that use spores for reproduction have gametophytes that depend on their sporophyte mother plants until they become a sporophytes themselves.
Interesting fact: Gametophytes do not look yet like the ferny sporophytes they will become. As they can live independently, there have been found fern gametophytes of which no one knows what the mature plant looks like.
Phytoremediation: Ferns Filter Toxins Out Of the Air and Soil
Ferns are important in their role in phytoremediation practices. Phytoremediation is a scientific field in which plants are used to filter pollutants out of our environment such as heavy metals or other toxins.
Ferns such as the Boston Fern or the Blue Star Fern have shown the ability to extract heavy metal arsenic from the soil and absorb it into their leaves. By doing so, the soil can be cleansed, capturing all arsenic in the plant itself.
From the air, ferns can filter out harmful volatile organic compounds (VOCs) such as formaldehyde, xylene, and tulol.
Medicinal Properties: How Ferns Help the Human Body
Ferns have been medicinally used by indigenous groups for hundreds of years. A wide range of illnesses was cured with leaf extracts, such as rheumatism, cough, menstrual pain, intestinal issues, and many more.
In search of new cures and medicaments, also current scientific pharmacological research is investigating the potential of ferns as a medicine.
Craft Resource: Making Baskets Out Of Ferns
Various types of ferns have also been used for artisanal crafting, such as for weaving. The strong and elastic fibers of fern stems can be dried and then weaved into the desired shape. Specifically Vietnam is known for its elaborate woven baskets.
Why Do Ferns Live In Moist Environments?
Most species of ferns today grow in the tropics or subtropics in rather moist environments. As ferns reproduce by spores, a humid and moist environment is preferable.
Spores sit on the leaf undersides exposed to the environment. A moist environment prevents the spores from drying out and water is necessary for the sexual reproduction of the spores.
Furthermore, a lot of ferns live as epiphytes on trees and other surfaces. The only way they can reach water is through rain or humidity. A tropical humid climate is more suitable for an epiphytic lifestyle than arid, dry regions.
Why Are Ferns So Difficult As Houseplants?
If ferns have survived so many evolutionary changes on this planet, how come they succumb to inadequate human treatment as houseplants so fast? Shouldn’t they be the pro-survivalists even indoors?
As I mentioned above, ferns are indeed ecological opportunists that grow in even extreme habitats. However, they survived exactly because they evolved to fit niches that no other plant fits in. The sensitive ferns can’t compete with the competitive tree-climber plants striving for light such as Monsteras, Pothos, or Philodendrons.
With ferns being specialized in very specific niche climates, it is difficult for them to feel well in any other type of habitat. They are not all-rounders growing anywhere happily.
You don’t have to start with the trickiest of ferns for your plant collection! There are a few that can do well with less humidity as well. Here are two fern species that are very common indoor plants and are not the most sensitive:
- Blue Star Fern: The Blue Star Fern (Phlebodium aureum) can do well with standard indoor humidity but likes to have it a little brighter than other ferns.
- Boston Fern: The Boston Fern (Nephrolepsis exaltata) is a common guest in many households. It is not super sensitive concerning the humidity and it does well in half-shade up to bright indirect light.
Nevertheless, ferns are fast forgiven for their tricky attitude as they add a beautiful and serene atmosphere to any room and should not be missing from your indoor plant jungle. Who wouldn’t want an ancient plant dinosaur in their home who has been around for longer than we can imagine?
There is also a sense of achievement in keeping a fern happy. If you manage to keep a fern alive in your home, know that you have certainly gained a master skill level and can be a proud plant parent!