“Plant” is a broad biological category, while “tree” describes a particular growth form found within the plant kingdom. A grass, fern, cactus, orchid and oak are all plants, but only some plants grow as trees.
There is no single universally accepted biological rule that separates every tree from every shrub. In general, trees are perennial woody plants with a dominant stem or trunk and a substantial height at maturity.
At a glance
| Point | Plant | Tree |
|---|---|---|
| Taxonomic level | Broad biological kingdom/category | Not one taxonomic group; trees evolved in many plant lineages |
| Stem | May be soft, herbaceous or woody | Woody stem/trunk |
| Height | Can range from tiny to enormous | Generally relatively tall at maturity |
| Lifespan | Annual, biennial or perennial | Typically perennial |
| Branching | Any growth form | Usually crown/branches above a main stem, though forms vary |
| Examples | Grass, rose, fern, moss, pine, oak | Oak, pine, baobab, maple, many palms by common usage |
Plant
A member of the plant kingdom; plants include tiny herbs, grasses, mosses, ferns, vines, shrubs and trees.
Tree
A perennial woody plant growth form, commonly characterized by a main trunk, secondary branches and continued woody growth over many years.
Tree is a growth form, not one family
Conifers, flowering plants and other lineages can independently grow as trees. That means two tree species can be less closely related to each other than one of them is to a non-tree plant.
Biologists therefore do not place all trees into a single “tree family.”
Trees produce secondary growth
Many classic trees increase trunk diameter through secondary growth produced by vascular cambia, generating wood. This gives them strength to support large crowns and live for decades or centuries.
There are exceptions and alternative structures—for example palms have a different stem anatomy from oaks—but are still commonly called trees because of their overall growth form.
Tree vs shrub
A shrub is generally shorter and often has several woody stems arising near the base, while a tree commonly has one dominant trunk. Nature does not always respect these neat categories; species and growing conditions can produce intermediate forms.
For landscaping or legal definitions, local standards may set practical height or stem criteria.
Frequently asked questions
Is a tree a plant?
Yes. Trees are plants.
Are all woody plants trees?
No. Shrubs and woody vines are also woody plants.
Are palms trees?
They are commonly called trees because of their tall trunk-like growth form, even though their internal stem structure differs from typical woody dicot trees.
Is bamboo a tree?
Bamboo is a grass. Some species grow very tall and woody-looking, but botanically they belong to the grass family.
Sources and further reading
KnowDifferences Editorial Team
Independent explanations with definitions, practical examples and references. Read our editorial approach.