Finding weeds with thorns on your lawn can be a bit disheartening, because not only do they affect the stunning appeal, but can also be harmful to you and other members of your home.
If you have weeds in your yard that have thorns and are not sure what they are or how to treat them, then this weed directory is for you. I have listed the most common weeds that grow in all regions of North America.
Spotting weeds with thorns is also a tricky task, but here’s how to identify and get rid of them easily.
Most Common Weeds with Thorns in the USA & Canada
Cocklebur (Xanthium Strumarium) Identification
Cocklebur (Xanthium Strumarium) is a very common thorny weed that is considered a nuisance to livestock producers.
This annual weed is claimed to have originated from North America and is found throughout the United States.
Cocklebur reproduces solely by seed and reaches heights between 30-150 cms. It is easy to identify spots and short hairs.
This weed is greenish in color, and bears elliptic to egg-shaped fruit, that grows between 0.5-1.5 inches long, and has hooked prickles.
It features stout, forked spines at the base of each leaf, which can hook onto your clothing, and become tightly attached.
Cocklebur (Xanthium strumarium) can be found in small streams, roadsides, and riverbanks, and can be removed by hand for populations prior to flowering.
There are also several herbicides to control Cocklebur including 2,4-D amine, Dicamba, Bromoxynil, and selective weed oils.
How To Treat (Kill) Cocklebur
My go-to product to prevent, control, and kill Cocklebur is: Roundup Pro
- Round Up Pro is used in many situations from agricultural farming to...
- Easy to use
- Non-Selective Herbicide
- Rainfast in just one hour
Prickly Sida Identification
Commonly known as teaweed, Prickly Sida is a summer annual that is one of the most common and troublesome weeds in cotton, peanuts, and soybeans in most of the southern states.
Even though teaweed is primarily a weed of agronomic crops, it can also be found in landscapes, horticultural crops, hayfields, pastures, and gardens.
It features yellow flowers and very small spines located at the base of each leaf and branch. The cotyledons of teaweed are typically heart-shaped with a small indentation at the apexes.
The leaves of Prickly Sida measure between 3/4 to 2 inches long, and are neatly arranged along the stem. The stems of teaweed are erect, branched, and grow between 8 – 20 inches in height.
Prickly Sida can be easily identified in several ways, starting with its seedlings, which feature two heart-shaped cotyledons and feature small thorns located at the base of each leaf.
You can prevent Prickly Sida from becoming a major problem by hoeing, hand pulling, and mulching when the weather gets warm.
If Prickly Sida has emerged prior to planting, Burndown applications of glyphosate, glufosinate, or paraquat are generally effective at getting rid of this weed.
- Round Up Pro is used in many situations from agricultural farming to...
- Easy to use
- Non-Selective Herbicide
- Rainfast in just one hour
How To Treat Prickly Sida
To kill and control Prickly Sida I use a product called: Triclopyr 4
- Triclopyr 4 Herbicide is a herbicide for control of woody plants,...
Weedy Brambles Identification
There are hundreds of different species of brambles, and each is easily recognizable with its woody, thorny stems, and vigorous root systems.
Woody brambles have long stems that grow flowers and fruit in their second year. These rough, tangled, prickly shrubs can be difficult to eradicate once they become established.
They scramble over the ground and low plants and spread via its rhizomes. Woody brambles feature variously shaped (usually cut-edged flat leaves, and white to pink five-petalled flowers followed by clusters of blackberries.
Wood brambles can cause low to moderate damage in open habitats and can inhibit the establishment of native plant seedlings.
To get rid of wood brambles, you can dig out small patches of the weed all year round, and burn the roots or bury them deeply.
The best time to dig wood bramble roots is when the soil is moist and forgiving. You can mow over wood bramble to keep the stems short, but doing so will encourage the growth of suckers from the lateral roots.
On a brighter note, the leaves of wood brambles can be used to treat stomach problems and diarrhea.
Thistles (Cirsium spp.) Identification
Declared a noxious weed by the state of Vermont in 1795, Cirsium is commonly known as plum thistles and belongs to the genus of perennial and biennial flowering plants in the Asteraceae.
This thorny weed is native to Eurasia and northern Africa, with roughly 60 species from North America.
Most species of Cirsium are considered weeds, but there are a few species that are cultivated in wildflower plantings and gardens for their aesthetic value.
Cirsium grows 1-5 ft. (0.3-1.5 m) tall with roots deep underground. It features dark green, prickly leaves, which have short, white hairs on their underside.
The flower heads of thistles can be of different colors including rose, purple, pink, yellow, or white.
Thistles can spread quickly by seed, and also by rhizomes underground. To get rid of thistle seedlings and small plants, you can cover with mulch to eliminate seed germination, and snip small thistles at the soil level.
You will have to dig the rhizomes out with a sharp shovel or similar tool. You can hand weed them out as well, but this isn’t such a good idea for an entire lawn.
If you have large infestations of thistles, you may have to spray a week killer of your choice.
Thorn Apple Identification
Datura stramonium, commonly known as devil’s snare, devil’s trumpet, jimson weed, or thorn apple is a species of flowering plant in the nightshade family Solanaceae.
It is likely to have originated from Central America and has since made its way to several world regions.
Thorn Apple is an aggressive invasive weed that thrives in temperate climates across the world. It’s an erect annual that grows leaves about 8 to 20 cm (3–8 in) long.
The leaves of thorn apple are densely hairy, especially on the underside. Thorn apple grows trumpet-shaped fragrant flowers that can be white, yellow, pink, or purple, which produce a thorny capsule fruit with numerous seeds.
Getting rid of thorn apple can be done with a broad-spectrum herbicide, spraying a herbicide will kill any thorn apple seeds it has distributed but make sure you spray the herbicide carefully only on the thorn apple weed, and not your desirable plants.
If you have a heavy infestation, lay black plastic over the area after digging up the existing thorn apple plants from the ground.
Dispose of the dead and dug-up thorn apple plants in an area such as a garbage can or trash dumpster, or where regrowth will be prevented.
Mimosa Diplotricha Identification
Mimosa diplotricha is an invasive weed that’s native to the Neotropics. Commonly known as Nila grass, the giant false sensitive plant or giant sensitive plant, Mimosa Diplotricha was first described in 1869 by American botanist Charles Wright, and grows either as an erect shrub or a scrambling climber.
Mimosa Diplotricha can be easily identified with its bipinnate and bright green leaves with a feathery appearance. Each leaf of Mimosa Diplotricha contains roughly 20 pairs of leaflets that are arranged opposite each other.
The stems of Mimosa Diplotricha are very long and feature a very sharp row of recurved thorns.
Mimosa Diplotricha typically flowers and seeds from April through the end of June, and spread through seeds, which are transported by running water, stock, and contaminated earth and /or vehicles.
The best approach to combat Mimosa Diplotricha is by combining several different methods together. You can use a picloram- or triclopyr-based broadleaf herbicide such as Tordon K to kill Mimosa Diplotricha.
Start by loading your sprayer with the herbicide, spray Mimosa Diplotricha in a methodical pattern, wait 90 days, and repeat the process if necessary.
Hawthorn Identification
Scientifically named Crataegus Monogyna Jacq, Hawthorn is a weed that crops up in humid and sub-humid temperate regions. It grows well in most soils and is a weed of lowland grasslands and grassy woodlands.
Originating from Europe, Hawthorn features hairless much-branched stems that are reddish-brown when young but turn grey when they mature, and at this time grow stiff spines that measure up to 12mm long.
This deciduous shrub or small tree’s hairless triangular leaves are a treat for slugs and certain other insects.
Blackberry (Rubus fruticosus)
Found throughout the USA. A woody shrub with long, thorny canes that can grow up to 10 feet tall. The thorns are long and curved, up to 1 inch long. To control, cut down the canes to the ground and apply a systemic herbicide. Repeat treatment as necessary.
Bull Thistle (Cirsium vulgare)
Found in many regions of the USA. A biennial or short-lived perennial with large, spiny leaves and stems that can grow up to 6 feet tall. The thorns are sharp, straight and up to 1 inch long. To control, hand-pull or mow the plants when they are young, before they have a chance to produce seeds.
Canada Thistle (Cirsium arvense)
Found throughout the USA. A perennial weed with spiny leaves and stems that can grow up to 3 feet tall. The thorns are short and needle-like, up to 1/2 inch long. To control, cut down the plants to the ground and apply a systemic herbicide. Repeat treatment as necessary.
Honey Locust (Gleditsia triacanthos)
Found in the eastern USA. A tree that can grow up to 70 feet tall, with long, straight thorns up to 4 inches long. The thorns are straight and sharp. To control, cut down the tree and remove the roots, or apply a systemic herbicide to the foliage.
Multiflora Rose (Rosa multiflora)
Found throughout the USA. A shrub that can grow up to 10 feet tall, with large, dense clusters of white or pink flowers and long, curved thorns up to 1 inch long. To control, cut down the shrubs to the ground and apply a systemic herbicide. Repeat treatment as necessary.
Burdock (Arctium minus)
Found in many regions of the USA. A biennial or perennial with large, spiny leaves and stems that can grow up to 6 feet tall. The thorns are straight and sharp, up to 1 inch long. To control, hand-pull or mow the plants when they are young, before they have a chance to produce seeds.
Wild Raspberry (Rubus idaeus)
Found throughout the USA. A shrub that can grow up to 6 feet tall, with thorny stems and clusters of red or black berries. The thorns are straight and sharp, up to 1 inch long. To control, cut down the shrubs to the ground and apply a systemic herbicide. Repeat treatment as necessary.
Wild Black Cherry (Prunus serotina)
Found throughout the USA. A tree that can grow up to 100 feet tall, with small, hooked thorns on the twigs and branches. The thorns are small, up to 1/2 inch long. To control, cut down the tree and remove the roots, or apply a systemic herbicide to the foliage.
Buckthorn (Rhamnus spp.)
Found in many regions of the USA. A shrub or small tree that can grow up to 30 feet tall, with dense, spiny branches. The thorns are straight and sharp, up to 1 inch long. To control, cut down the shrubs or trees to the ground and remove the roots, or apply a systemic herbicide to the foliage.
Prickly Ash (Zanthoxylum americanum)
Found throughout the USA. A shrub or small tree that can grow up to 30 feet tall, with spiny twigs and branches. The thorns are short and needle-like, up to 1/2 inch long. To control, cut down the shrubs or trees to the ground and remove the roots, or apply a systemic herbicide to the foliage.
Spiny Amaranth (Amaranthus spinosus)
Found throughout the USA. An annual weed with spiny stems and leaves that can grow up to 5 feet tall. The thorns are small, needle-like and sharp, up to 1/2 inch long. To control, hand-pull or hoe the plants when they are young, or apply a pre-emergent herbicide to prevent germination.
Wild Rose (Rosa spp.)
Found throughout the USA. A shrub with thorny stems and clusters of flowers that can grow up to 10 feet tall. The thorns are straight and sharp, up to 1 inch long. To control, cut down the shrubs to the ground and apply a systemic herbicide. Repeat treatment as necessary.
Wild Grape (Vitis spp.)
Found throughout the USA. A vine that can grow up to 100 feet long, with thorny tendrils and clusters of grapes. The thorns are small and sharp, up to 1/2 inch long. To control, cut down the vines and remove the roots, or apply a systemic herbicide to the foliage.
Cactus (Opuntia spp.)
Found in the southwestern USA. A succulent with spiny stems and leaves that can grow up to 6 feet tall. The thorns are long and sharp, up to 1 inch long. To control, cut down the plants to the ground and remove the roots, or apply a systemic herbicide to the foliage.
Cocklebur (Xanthium spp.)
Found throughout the USA. An annual weed with spiny burs and stems that can grow up to 6 feet tall. The thorns are short and needle-like, up to 1/2 inch long. To control, hand-pull or hoe the plants when they are young, or apply a pre-emergent herbicide to prevent germination.
Wild Mustard (Brassica spp.)
Found throughout the USA. An annual weed with spiny stems and leaves that can grow up to 6 feet tall. The thorns are small and needle-like, up to 1/2 inch long. To control, hand-pull or hoe the plants when they are young, or apply a pre-emergent herbicide to prevent germination.
Wild Onions (Allium spp.)
Found throughout the USA. A bulb-forming perennial weed with spiny leaves and stems that can grow up to 2 feet tall. The thorns are small and needle-like, up to 1/2 inch long. To control, hand-pull or hoe the plants when they are young, or apply a systemic herbicide.
Wild Carrot (Daucus carota)
Found throughout the USA. A biennial or short-lived perennial weed with spiny stems and leaves that can grow up to 4 feet tall. The thorns are small and needle-like, up to 1/2 inch long. To control, hand-pull or hoe the plants when they are young, or apply a pre-emergent herbicide to prevent germination.
Field Horsetail (Equisetum arvense)
Found throughout the USA. A perennial weed with spiny stems and leaves that can grow up to 3 feet tall. The thorns are small and needle-like, up to 1/2 inch long. To control, hand-pull or hoe the plants when they are young, or apply a systemic herbicide.
Wild Garlic (Allium vineale)
Found throughout the USA. A bulb-forming perennial weed with spiny leaves and stems that can grow up to 2 feet tall. The thorns are small and needle-like, up to 1/2 inch long. To control, hand-pull or hoe the plants when they are young, or apply a systemic herbicide.
Spanish Needles (Bidens spp.)
Found throughout the USA. An annual weed with spiny burs and stems that can grow up to 6 feet tall. The thorns are short and needle-like, up to 1/2 inch long. To control, hand-pull or hoe the plants when they are young, or apply a pre-emergent herbicide to prevent germination.
Wild Lettuce (Lactuca spp.)
Found throughout the USA. An annual or biennial weed with spiny stems and leaves that can grow up to 6 feet tall. The thorns are small and needle-like, up to 1/2 inch long. To control, hand-pull or hoe the plants when they are young, or apply a pre-emergent herbicide to prevent germination.
Common Thistle (Cirsium spp.)
Found throughout the USA. A biennial or perennial weed with spiny stems and leaves that can grow up to 6 feet tall. The thorns are long and sharp, up to 2 inches long. To control, hand-pull or hoe the plants when they are young, or apply a systemic herbicide.
Wild Cherry (Prunus spp.)
Found throughout the USA. A shrub or small tree with thorny stems and clusters of cherries that can grow up to 30 feet tall. The thorns are short and sharp, up to 1/2 inch long. To control, cut down the shrubs or trees to the ground and remove the roots, or apply a systemic herbicide to the foliage.
Wild Blackberry (Rubus spp.)
Found throughout the USA. A shrub with thorny stems and clusters of blackberries that can grow up to 10 feet tall. The thorns are long and sharp, up to 2 inches long. To control, cut down the shrubs to the ground and apply a systemic herbicide. Repeat treatment as necessary.
Wild Plum (Prunus spp.)
Found throughout the USA. A shrub or small tree with thorny stems and clusters of plums that can grow up to 30 feet tall. The thorns are short and sharp, up to 1/2 inch long. To control, cut down the shrubs or trees to the ground and remove the roots, or apply a systemic herbicide to the foliage.
Wild Apple (Malus spp.)
Found throughout the USA. A shrub or small tree with thorny stems and clusters of apples that can grow up to 30 feet tall. The thorns are short and sharp, up to 1/2 inch long. To control, cut down the shrubs or trees to the ground and remove the roots, or apply a systemic herbicide to the foliage.
Bull Thistle (Cirsium vulgare)
Found throughout the USA. A biennial or perennial weed with spiny stems and leaves that can grow up to 6 feet tall. The thorns are long and sharp, up to 2 inches long. To control, hand-pull or hoe the plants when they are young, or apply a systemic herbicide. Regular mowing may also help prevent seed production.
Wild Rose (Rosa spp.)
Found throughout the USA. A shrub with thorny stems and clusters of roses that can grow up to 10 feet tall. The thorns are short and sharp, up to 1 inch long. To control, cut down the shrubs to the ground and apply a systemic herbicide, or cover the area with mulch or ground cover plants to prevent re-growth.
Wild Buckthorn (Rhamnus spp.)
Found throughout the USA. A shrub or small tree with thorny stems that can grow up to 20 feet tall. The thorns are short and sharp, up to 1 inch long. To control, cut down the shrubs or trees to the ground and remove the roots, or apply a systemic herbicide to the foliage.
Also see: Weeds that look like Rhubarb
