Types of Trees With Thorns (Pictures and Names) – Identification Guide

Thorny trees are characterized by having large, pointed spikes or barbs growing on their trunks or stems. Trees with thorns can be dangerous because the sharp spikes can cause injury if you brush against them. Additionally, the thorns on some trees may be hidden under leaves or hard to spot growing in the joints of branches and twigs.

Some of the most well-known trees with thorns are the locust tree, acacia tree, hawthorn tree, and floss silk tree. Thorny trees, like the locust tree, have clusters of sharp spikes on their trunks. However, the silk floss tree has jagged protrusions all the way up its straight trunk. But the spiky hawthorn has thin branches with sparsely growing needle-like thorns.

Trees with thorns come in all shapes and sizes. And it’s good to know how to identify prickly trees without getting too close. This is because the sharp piercing barbs can puncture footwear and cause injury.

This article is a guide to identifying the most common thorny trees in a landscape. Pictures and descriptions of the trees’ spiky growths and other characteristics will help recognize these thorny plants.

What Are Trees With Thorns?

Thorny trees are species of tall plants with prickly bark, stems, or branches. The barbed growths can grow in small clusters giving the tree a spiky appearance. Or the sharp thorns can grow singularly along slender twigs. Trees with thorns range from the acacia with its sprawling crown to the small shrub-like hawthorn tree.

Many people may refer to trees and bushes as thorny plants if they have spiny, jagged leaves. For example, the holly tree and Oregon grape holly shrub have prickly, leathery leaves. However, this article only refers to trees that have spikes, thorns, or barbs growing on bark or twigs.

Related reading: Thorny bushes for your garden.

Thorns vs. spines vs. prickles

The terms thorns, spines, and prickles are often used interchangeably. However, there are slight differences between these jaggy growths. Thorns are modified shoots like on a honey locust or hawthorn tree. Prickles are spikes attached to the plant’s bark, like those on a rose bush. And spines grow from leaf tissues like a holly or barberry shrub.

How to Handle Thorny Trees

Maintaining thorny trees in a garden landscape can be challenging. Care is necessary when pruning trees and when walking near the prickly specimens. Therefore, you should wear appropriate footwear that protects against slipping. Also, put on heavy-duty gloves and safety goggles to stay safe from getting jagged or puncturing your skin.

How to Identify Trees With Thorns

Identifying trees with thorns involves observing the growth characteristics of the spiky tree. You should look at the shape of the crown, its height, leaf shape, and flowers. Up close, you can identify the tree by how the thorny spiky protrusions grow and their length.

Trees With Thorns (With Pictures) — Identification Guide

Let’s look in detail at 14 species of thorny trees that you may find in a landscape.

Acacia Tree (Acacia)

Many species of acacia trees have sharp thorns covering their branches. The acacia tree is typically recognized by its flat-topped, spreading crown, foliage consisting of pinnate leaves with small oval leaflets and small flowers. Typically, acacia trees growing in arid regions develop clusters of sharp spikes on branches.

Acacia trees grow between 13 to 20 ft. (4 – 6 m) tall with an umbrella-shaped canopy measuring 26 ft. (8 m) in diameter. These trees are well suited to growing in the desert because they tolerate drought and hot sunshine.

Other names for acacia trees include thorntree, mimosa, or wattle tree.

Thorny tree identification

Acacia trees are identified by their grayish-white sharp spikes growing in pairs on reddish-brown branches. Also, acacia trees have easily identifiable leaves that resemble those on a mimosa plant.

Honey Locust Tree (Gleditsia triacanthos)

The honey locust tree is a large, fast-growing deciduous tree with a trunk covered in large, sharp branched spikes. The menacing locust tree thorns can only be described as vicious. Other identifying features of locust trees are their pinnately compound leaves, long reddish-brown seed pods, and small clusters of greenish-yellow flowers.

The honey locust tree grows 60 to 80 ft. (18 – 24 m) tall and wide. The extremely sharp thorny spikes grow up to 3” (7.5 cm) long. It also has easily recognizable mimosa-like feathery leaves consisting of tiny oval leaflets. In the fall, honey locust trees turn golden yellow before dropping their leaves.

Honey locust trees are not suitable for residential landscapes. However, thornless cultivars like Gleditsia triacanthos var. inermis aren’t as dangerous as the specimen tree.

Thorny tree identification

The thorn-laden honey locust tree is identified by its stout, needle-sharp thorns, with some reaching over 8” (20 cm) long. The pinnately compound leaves are bright green in summer and yellow in the fall.

Black Locust (False Acacia) Tree (Robinia pseudoacacia)

The black locust is a medium-sized deciduous tree with small sharp thorns growing along its branches. The shrub-like tree tends to be weedy and vigorously produces suckers. The black locust has pinnately compound leaves, dangling clusters of white pea-like flowers, and reddish-brown flattened seed pods.

Black locust trees grow 30 to 50 ft. (9 – 15 m) tall and up to 35 ft. (10.5 m) wide. The pinnately compound leaves grow 8” to 14” (20 – 35 cm) long, each containing 7 to 21 leaflets. The showy, fragrant wisteria-like white flower clusters measure 8” (20 cm) long and develop into long seed pods.

Black locust trees thrive in USDA zones 3 to 9 and require full sun or partial shade and well-drained soil.

Thorny tree identification

The identifying features of a black locust tree are its thorny brittle branches, dark brown to black furrowed bark, and fragrant white flowers.

Hawthorn Tree (Crataegus)

Hawthorn trees have sharp-tipped thorns growing on the bark or branches. The sharp thorns can be multi-branched, making them even more dangerous. Leaves on hawthorn trees are small oval leaves with deep lobbing, giving them the appearance of parsley leaves. The trees and shrubs have large clusters of creamy-white flowers.

Species of hawthorn are either large thorny shrubs or small trees with spikes. The prickly trees grow 15 – 50 ft. (5 – 15 m) tall. Usually, the stiff thorns typically grow between 1” and 3” (2.5 – 7.5 cm) long, and the flat-topped scented flower clusters cover the tree in late May or early June.

Another attractive feature of ornamental hawthorn trees is their beautiful leaves that emerge reddish-purple in spring and turn green in summer before changing to bright red, purple, or orange in the fall.

Thorny tree identification

A hawthorn tree is recognized by its rounded, spreading crown, masses of white spring flowers, and red berry-like drupes in the fall. In addition, hawthorn tree branches have characteristic spiky thorns measuring around 1” (2.5 cm) or longer.

Mesquite Tree (Prosopis)

Mesquite trees are small, multi-stemmed trees, and several varieties grow stiff, sharp thorns on the branches. The nail-like spikes can grow around 3” (7.5 cm) long and easily puncture the skin. Mesquite flowers are fuzzy spikes of yellowish flowers that bloom in spring and summer, followed by dangling bean pods.

Mesquite trees grow up to 26 ft. (8 m) tall and wide. The trees are characterized by crooked branches, feathery, pinnately compound leaves, and stout thorns typically growing in pairs.

Mesquite trees adapt well to growing in the desert. The small shrub-like trees have deep taproots, and the foliage is highly tolerant of heat. You can also grow a mesquite tree in a residential landscape as a shade tree for dappled shade or lawn tree. And it’s possible to buy thornless varieties.

Thorny tree identification

Mesquite trees are identified by their yellowish-brown sharp thorns, slender bipinnately compound leaves, and yellow flowering spikes.

Palo Verde Tree (Parkinsonia)

The palo verde tree is a small prickly tropical tree characterized by its upright growing thorny branches. Apart from its reddish thorns on green branches, palo verde trees are recognized by their yellow and orange showy flowers that cover the trees through warm weather in USDA zones 8 to 11.

Palo verde trees grow 16 to 40 ft. (5 – 12 m) tall and have an upright branching habit and vase shape. The heat-loving yellow-flowering trees bloom after rains but lose their bipinnately compound leaves during dry summers. Small palo verde shrubs grow as dense thickets.

Thorny tree identification

Identifying features of the palo verde tree are its yellow flowers with orange patches, long 5-inch (12 cm) bean pods, and sharp barbs growing along its branches.

Floss Silk Tree (Ceiba speciosa)

The floss silk tree is an unusual tropical tree that develops spiky conical prickles on its erect trunk, giving it an armored appearance. The tree’s horizontal branches (also covered in prickles) grow to form an attractive rounded canopy. Dark green, dense foliage covers the tree contrasting with the showy pink hibiscus-like flowers.

The floss silk tree grows up to 82 ft. (25 m) and has a bottle-shaped trunk that bulges near the base. The pink flowers, with their creamy-white and yellow centers, measure 4” to 6” (10 – 15 cm) in diameter and have five slender petals in a star shape.

Thorny tree identification

The floss silk tree is easily identified due to its grayish conical prickles covering the cylindrical green trunk.

Sandbox Tree (Hura crepitans)

The sandbox tree is identified by its smooth brown bark covered in extremely sharp, pyramid-shaped pointed prickles. This tropical tree has several unusual growth features. The sandbox tree produces small red petal-less flowers, large ovate leaves up to 2 ft. (0.6 m) wide, and small roundish pumpkin-like fruits that explode when ripe.

The vast sandbox tree grows 200 ft. (60 m) tall and thrives in wet soils in USDA zones 10 and 11.

Thorny tree identification

The sandbox tree is easily identifiable due to its sharp, prickly protrusions on its trunk, enormous size, and exploding fruit.

Devil’s Walking Stick (Aralia spinosa)

The devil’s walking stick tree is a small deciduous tree with slender stems covered in curved, fiercely sharp brown to tan spines. The tropical-looking spiny tree has large leaves measuring up to 45” (120 cm) long and a rounded, umbrella-shaped crown. The tree blooms in late summer with small, creamy-white flowers that develop into purplish-black berries.

With its spiny stems, the devil’s walking stick grows up to 26 ft. (8 m) tall. Its unique features are huge tropical leaves and stems with stout, sharp spines. Additionally, the tree has creamy-white flowers blooming late in summer, followed by black fleshy fruits.

Thorny tree identification

The devil’s walking stick is identified by its upright stems with ferociously sharp spines, large tropical leaves, and clusters of feathery creamy-white flowers.

Kapok (Ceiba pentandra)

Kapok is a species of large tree with sharp thorns growing extensively on its bark. Kapok trees are identified by their thorny buttress roots, large palmate leaves, and clusters of tiny yellowish-white flowers. The unique characteristic of the tree is its cotton-like downy substance surrounding the seed pods.

Kapok trees are giant tropical trees that thrive in USDA zones 10 to 12. The thorny trees can grow 75 to 125 ft. (22 – 38 m) tall and up to 75 ft. (22 m) wide.

Thorny tree identification

The thorny kapok tree is identified by its straight trunk covered in stout, sharp thorns, palmate compound leaves, and creamy-white flower clusters consisting of bell-shaped flowers.

Chittamwood Tree (Sideroxylon lanuginosum)

Chittamwood tree is a small, shrub-like tree with thorny branches. Identifying characteristics of the deciduous tree are its spiny, stiff, woolly branches, oblong green leaves with fuzzy undersides, and clusters of purplish-black fruits. The multi-stemmed spiny tree grows up to 40 ft. (12 m) tall and has a straight trunk and rounded, narrow crown.

Common names of Sideroxylon lanuginosum describe many of its growth habits. For example, woolly buckthorn, gum bumelia, and gum bully refer to its fuzzy leaves and sticky gum-like substance the tree produces.

Thorny tree identification

The chittamwood tree is identified by its straight trunk with dark bark, stiff branches, sharp spines, and oblong oval leaves.

Osage Orange (Maclura pomifera)

The osage orange tree is a mid-sized, multi-stemmed tree with stout, sharp thorns on its interlacing branches. This thorny deciduous tree has a rounded crown of shiny, dark green leaves and small greenish spring flowers. The unique feature of this thorny tree is its large grapefruit-like round yellowish-green fruits.

Osage orange trees grow 25 to 60 ft. (7.5 – 18 m) tall. Its unusual round, inedible fruits are about the size of a baseball. Due to the nasty thorns on the small shrub-like tree, the plant can be used as a security hedge or living fence.

It thrives in USDA zones 4 to 9.

Thorny tree identification

Osage orange is identified by its thorny branches, large orange-like fruit, and rounded crown.

Pejibaye (Peach) Palm (Bactris gasipaes)

Peach palm trees are an unusual species of palm due to the sharp black spines covering its trunk. These palm trees have the characteristic slender palm trunk and rounded crown, large arching pinnate leaves growing 10 ft. (3 m) long, and reddish, orange, or yellow palm fruits. Spiny pejibaye palms grow 66 ft. (20 m) tall.

An unusual feature of peach palm trees is their clusters of cylindrical yellow inflorescences. These develop into large bunches of edible egg-shaped fruits 2.3” (6 cm) long and known for their nutty flavor.

Thorny tree identification

Pejibaye palm trees are easy to identify due to their tall, slender trunks densely covered in black spines measuring 2” (5 cm) long.

Pochote (Pachira quinata)

Pochote is a species of flowering tree characterized by masses of sharp, stubby thorns covering its branches and trunk. The spiny tree is identified by its palmate leaves with five obovate leaflets, flowering with slender, wiry petals, and fruits containing seeds covered in cotton-like hairs. Thorny pochote trees grow 20 to 103 ft. (6 – 40 m) tall.

Discover many types of thorny bushes and vines (with pictures).

Related articles:

• Acacia Trees – Types and Identification
• Locust Trees – Types and Identification
• Hawthorn Trees – Types and Identification