Is There a World's Smallest Tree Species?

Some people claim that the title "World's Smallest Tree" should go to a tiny plant that grows in the coldest regions of the Northern Hemisphere.

Salix herbacea, or dwarf willow, is described by some internet sources as the very smallest tree in the world. It is also known as the least willow or the snowbed willow.

Others see the "tree" as a woody shrub that does not meet the definition of a tree accepted by botanists and foresters.

Definition of a Tree

The definition of a tree that most tree scholars recognize is "a woody plant with a single erect perennial trunk that reaches at least 3 inches in diameter at breast height (DBH) when mature."

That certainly does not fit the dwarf willow, although the plant is a willow family member.

Dwarf Willow

Dwarf Willow or Salix herbacea is one of the smallest woody plants in the world. It typically grows to only 1 centimeter to 6 centimeters in height and has round, shiny green leaves 1 centimeters to 2 centimeters long and broad.

Like all members of genus Salix, dwarf willow has both male and female catkins but on separate plants. The female catkins are red, while the male catkins are yellow.

Bonsai

If you don't buy into the dwarf willow being a tree, then perhaps the tiny bonsai crossed your mind.

While bonsai do, indeed, meet the definition of trees, they are not a species, as they alterations of larger trees, and can be made from different species. A person will take a cutting from a larger tree to make the miniature bonsai, which then must be carefully maintained and watered to keep its structure.

Real (Short) Trees

So how about a list of actual plants that meet the definition of trees that can mature at less than 10 feet tall?

Crape Myrtle: This small tree comes in a variety of sizes. It can be as short as 3 feet when fully grown, making it one of the shortest trees in the world, though some can reach 25 feet. It can grow quite fast, which is why it is vital to keep in mind its mature growth size when choosing a tree. They come in a variety of brilliant colors. 

‘Viridis’ Japanese maple: The Japanese maple grows only 4 feet to 6 feet tall, but spreads out like a bush. Its vivid green leaves turn to gold and crimson in the fall.

Weeping redbud: The Weeping redbud usually grows only 4 feet to 6 feet. They have a small trunk but will "weep" a flowing canopy back to the ground if not pruned.

Pygmy date palm: A dwarf palm tree, this species grows 6 feet to 12 feet tall, and can be kept in a container. Native to southeast Asia, it is relatively drought-tolerant, but can't stand temperatures below 26-degrees Fahrenheit.

Henry Anise: With its particularly dense evergreen broadleaf, Henry anise usually grows to be between 5 to 8 feet in a pyramid shape. It is known for its brilliant pink flowers and anise-scented leaves. It makes an excellent hedge.   

Japanese maple: Japanese maple can grow between 6 to 30 feet tall. It grows one to two feet per year. Native to Eastern Asia and southeast Russia, this plant comes in a variety of vibrant, eye-catching colors, such as red, pink, yellow and orange. 

 ‘Twisted Growth’ deodar cedar: This tree grows between 8 to 15 feet tall. The named comes from the twists in the limbs. The trees also have a droopy appearance.

Windmill palm: This tree typically grows 10 feet to 20 feet tall. The tree is native to portions of China, Japan, Myanmar, and India. It has no cold hardiness and is only cultivated in the United States in the extreme southern states and Hawaii or along the West Coast up to Washington and the most extreme southern tip of Alaska.

Lollipop crabapple: These trees grow to 10 feet to 15 feet and produce bushy, white flowers. The name comes from the fact that the tree looks like a lollypop with a small trunk like a lollypop stick and a big round bush of branches like the lollypop itself.

Blackhaw viburnum: This tree grows 10 feet to 15 feet tall, producing cream-colored flowers in spring and plum-colored leaves in fall. It is native to North America. It produces a fruit that can be made into preserves.

Hibiscus syriacus: This tree grows from 8 feet to 10 feet tall, and produces lavender flowers in the spring. It is native to parts of China but has been distributed throughout the world where it has various common names. In the United States, it is known as Rose of Sharon.