What a Plant Type Actually Means
Plant classification can be scientific or general. The botanical one relies on species' genetics, evolutionary history, and reproductive structures. The general one defines the types based on different factors — how the plant grows, what it looks like, and how it functions.
The key general types include flowers, trees, succulents, ferns, grasses, shrubs, vines, aquatics, carnivorous species, cycads, and mosses. For example, a tree is any plant with a single woody trunk that grows 16 feet (5 meters) tall, regardless of its family.
Shrubs and vines are also defined by their physical structure. Succulents and aquatics are defined by the environments to which they are adapted. Ferns and mosses are classified based on their reproductive features, as they reproduce without flowers or seeds.
Cycads are defined by producing cones instead of flowers. Carnivorous species are characterized by their unique feeding habits.
Plant Species by the Numbers
All types of plants combined account for 374,000 known species. But that distribution isn’t even.
These numbers aren’t final. Professional and citizen scientists discover around 2,000 new species every year.
Overlapping Types: Why a Single Plant Can Belong to Many Groups?
A type can be defined by a structure, reproductive system, and growth form. A single species can meet the criteria of a few such types at the same time.
For example, Giant Bamboo is a grass by its biology, but it can also be considered a tree by its structure. The Swamp Pitcher Plant is both a carnivorous species and a climbing vine.
The Hiddenfruit Bladderwort belongs to the three categories at the same time — it’s a carnivorous, aquatic, and flowering species.
The Age Gap Between Different Types of Plants
The main types have different evolutionary ages:
- Liverworts — the oldest type, emerged 470 million years ago and are still alive today.
- Ferns — appeared in the late Devonian around 360 million years ago.
- Mosses — first unambiguous fossils emerged around 300 million years ago.
- Cycads — appeared 280 million years ago before dinosaurs, dominated ecosystems during the Jurassic.
- Flowering species — appeared only 125-130 million years ago.
Though the flowering group arrived last, they now make up roughly 80% of all known plants on Earth.