Weed is a general term used to describe a plant growing in unwanted areas. Since the agricultural revolution, humans have tried to combat the invasion by weeds into farms, small gardens, and even pavements.
As invasive species, these plants have been changing over time, hence the relative name. Because weeds come in different types, the best way of identifying them is by their scientific names.
Here, we will describe the most common weeds and their scientific names.
Theoretically, every recognized plant on earth has a two-part scientific name. The system used to classify them is known as binomial nomenclature.
Scientific names of plants are descriptions to suggest something about them.
An advantage of identifying plants by their scientific names is it becomes easier to know how to control them and determine their usefulness.
Here is a list of weeds that you are likely to find in your garden or yard and their scientific names. We have included pictures too so that you can identify them easily.
1. African Feather Grass – Cenchrus macrourus
The African Feather Grass, also known as bedding grass, is a perennial, clump-forming grass that can reach a height of about two meters.
It has deep fibrous roots and rhizomes that form new plants. Its leaves are harsh, strongly ribbed, and tough.
The plant is dark-green underneath and light green on top. Its stems are round, purplish-white, and have fine hairs that break when touched, causing skin irritations.
As one of the many grass weeds, you can control it by slashing or burning it before its seeds set it. You can also apply glyphosate or flupropanate during periods of growth to eliminate it.
2. African Lily – Agapanthus praecox
The African lily, also known as the blue lily, is a well-known garden weed throughout the world. It is a perennial plant with open-faced flowers.
Its flowers are white, blue, or purple, and bloom in the summer. When you open its capsules, you will find fine black seeds.
As a homeowner, you should try and control this plant because it has powerful roots that can penetrate or break concrete. Unlike other weeds, the Agapanthus praecox is challenging to remove.
It is resistant to most herbicides. The best way of eliminating it is to dig it out and spray the area evenly using a chemical surfactant. You can also use vinegar to eliminate the weed.
3. African Lovegrass – Eragrostis curvula
The African Lovegrass or weeping lovegrass is one of the most common garden weeds whose scientific name is Eragrostis curvula.
It is a long-lived perennial grass that can also be an annual plant in some regions.
When growing, it forms a dense root network with tufts of stems that are about two meters long and a diameter of 8 centimeters.
Its leaves are hair-like, narrow, rough, and blue-green to bright green.
The weed is tough to control at home. Its roots can penetrate over four meters deep in the soil and three meters laterally.
Its seedlings can send out many small rootlets, thus creating a dense root system. A useful way of eliminating it is to till with a deep disc or plow in hot, dry weather.
4. Canada Thistle – Cirsium arvense
The Canada thistle is a perennial flowering plant that thrives in areas with moderate temperatures, sunlight, and lots of groundwater.
It can grow to a height of 1.5 meters with thickened roots that spread many erect shoots. Its leaves have wavy spiny or toothed margins that are alternate, irregularly shaped, and lance-shaped.
The stems of the plant are smooth with short hairs. Its flowers are pink and purple. Canada thistle is adaptive and the worst invasive weed.
Controlling it is through snipping off the base of the plant. Avoid pulling it out because it can split its roots and cause two more of the weed to grow back.
5. Common Chicory – Cichorium intybus
The Common Chicory is a woody, perennial herbaceous plant with bright blue flowers that can sometimes be pink or white.
It grows in the wild, especially on roadsides, and has a robust, grooved, and hairy stem. Its leaves are light purple or lavender, and it has broad flower heads.
As a weed, chicory adapts to well-drained soils in full sun. If it grows in your small garden, removing it by hand is the most practical method of controlling it.
But you must ensure you get rid of all its roots.
6. Common Self-heal – Prunella vulgaris
The Common Self-heal is a perennial herbaceous plant that grows to a height of 30 centimeters. Its stem is reddish, hard, and self-rooting.
Its leaves are lance-shaped, reddish at the axis, and serrated.
People who identify weeds by photos will notice that the common self-heal mostly grows on waste places, gardens, and roadsides.
If the plant is sprouting in lawns, control it by spraying a 2,4-D-based herbicide. Apply the treatment during chilly, moist, and calm climatic conditions.
7. Couch Grass – Elymus repens
The couch grass is a perennial weed characterized by creeping rhizomes that enable it to grow faster across grassland.
Its leaves are linear, flat, and hairy, with upright flower spikes. You can also identify it by the stems, which grow to a length of up to 1.5 meters.
Couch grass is one of the many naturalized weeds in the world categorized as invasive.
It can be challenging to remove it from the garden since the thin rhizomes can become twisted among shrubs.
Therefore, you can eliminate it by pulling it out during the spring. You can also dig deep in the ground to remove the entire grass.
8. Crabgrass – Digitaria sanguinalis
When you want to identify common weeds in the Digitaria sanguinalis class of species, you will come up with many names, including crabgrass, large crabgrass, purple crabgrass, and more.
It is a weed used as animal fodder with edible seeds. The crabgrass is an annual plant that has long, thin, radiating branches.
The crabgrass can be weedy or invasive. A practical way of killing it is to remove its visible clumps by pulling them out, including the roots.
Also, a simple solution of regular household vinegar and dish detergent can help to get rid of Digitaria sanguinalis.
If you want to prevent this grass from growing on your lawn, you should use a crabgrass preventer.
9. Dandelion – Taraxacum officinale
The Dandelion is a flowering herbaceous perennial plant. It is one of the many types of weeds that grow in temperate regions.
You will find them on lawns, on banks, on roadsides, on waterways, and on moist soils.
Its stems are upright, tinted purplish, and produce narrowly winged or unwinged leaves with yellow flower heads.
As a perennial plant, the best way of eliminating it from your lawn is to spray it with broadleaf herbicides. Herbicides will kill the entire plant, including the leaves and roots.
10. Duckweed – Portulaca oleracea
The duckweed, also known as common purslane, is an annual succulent characterized by smooth, reddish, prostrate stems. It can grow to a height of 40 centimeters with yellow flowers.
Its flowers can appear at any time of the year, especially with enough rainfall.
The duckweed has a taproot system with fibrous secondary roots. It can withstand poorly compacted soils and even grow in drought regions.
You can eliminate it by using 2,4-D-based herbicide or uprooting it using gardening tools.
11. English Plantain – Plantago lanceolata
The English plantain is a common rosette-forming perennial weed on cultivated land. It has a flower stalk that can produce up to two hundred seeds.
Plantago lanceolata can live in rainforest areas and dry meadows.
Although the plant has a taproot system, its ability to produce many seeds from one leaf makes it challenging to control. To eliminate it, start by pulling out the entire plant and root.
A rule of thumb is to pick off any flower stalks immediately after they begin to sprout to prevent them from spreading the seeds.
12. Groundsel – Senecio vulgaris
The Groundsel is an annual flowering plant that can grow to a height of 45 centimeters. It has sessile leaves that lack a stem and alternate in the direction along the length of the plant.
Its root system has a shallow taproot. Because of this trait, the weed can only spread by reseeding itself.
It is easy to control the groundsel because of its taproot system.
You can remove it by hand-pulling or cutting it off through hoeing. Ensure to eliminate the plant before it flowers and sets seed.
13. Ground Ivy – Glechoma hederacea
The Ground Ivy is a perennial plant considered an aggressive invasive weed. You will find it on most lawns because of its extensive root system. It is easy to identify it because its leaves are kidney-like or fan-shaped. The plant can spread by either its seed or stolon.
The Ground Ivy is a challenging plant to eradicate because of its root system and how it spreads.
It is the primary reason the weed has many other names, including creeping charlie, run-away-robin, and catsfoot.
You cannot eliminate it by hand-pulling. A practical way is to use a broadleaf herbicide that contains dicamba.
14. Knotgrass – Polygonum aviculare
The common Knotgrass, also known as prostrate knotweed, is an annual plant found in wastelands, arable land, and fields and grows mostly in temperate regions.
It has white flowers, a semi-erect stem, and hairless, short-stalked leaves. Its seeds need ample light to germinate and heavy rains of spring, hence the reason you will find it in disturbed soils.
It also has a long taproot that helps it to survive in hot climates.
The best way of eradicating the weed is to use glyphosate-based herbicides. Spray its leaves in the late summer or early autumn.
15. Orchardgrass – Dactylis glomerata
The Orchardgrass is a weed characterized by a dense network of non-rhizomatous roots. It is a perennial plant that can grow to a height of 120 centimeters.
Its leaves are V-shaped near the base and have a closed sheath.
Since its roots are dense, the plant tends to grow fast. Its rooting depths can reach up to two feet.
To control it, start by pulling it out and spraying the area using glyphosate herbicide.
16. Red dead-nettle – Lamium purpureum
The Red dead-nettle, also known as purple dead-nettle, is an annual herbaceous flowering plant characterized by a square stem that grows to a height of 20 centimeters.
Its leaves have fine hairs and are green in color at the bottom and purplish at the top. It has a taproot system that forms dense colonies by reseeding itself.
You can use glyphosate to control the weed while it is actively growing in spring or fall and in cold climates.
If you are a gardener, spread some mulch on the area you cleared to control the seeds.
17. Spotted Spurge – Euphorbia maculata
The Spotted Spurge is a fast-growing annual plant common in gardens and lawns. It is a weed that sprouts in sunny locations and different soils.
Its leaves are oval, its flowers are small with white petals, and its stem has a length of about 45 centimeters.
When you look at pictures of common weeds, you will notice that the Spotted Spurge is a small plant that you can remove by pulling.
But you should do it before it flowers and produces seeds. You can also kill it by using a weed killer or a non-selective herbicide containing 25% glyphosate.
18. Wild Madder – Rubia peregrine
The Wild Madder is a perennial herbaceous weed that grows in bushes, thickets, stony grounds, hedges, and along paths and roads.
It has a woody stem, which is also climbing, square, and hairless, and can reach a length of up to 2.5 meters. Its leaves are evergreen, sessile, leathery, and glossy.
As one of the common weeds and their botanical names on this list, Rubia peregrine refers to a plant that is resistant to stress.
You can eliminate it by using herbicides, burning, or uprooting it.
19. Yellow Foxtail – Setaria pumila
The Yellow Foxtail is an invasive annual weed that grows in lawns, roadsides, sidewalks, and other areas.
It can grow to a height of 20 centimeters and has a hairless stem whose color can range from purple-tinged to green. When growing, it tends to spread aggressively, making it difficult to control it.
If the weed has invaded your garden or sidewalk, eliminate it by pulling off its seed heads to prevent it from repopulating the same area.
You can also dig deep into the soil to remove its roots. Alternatively, use pre-emergence herbicides to kill it permanently.
20. Yellow Woodsorrel – Oxalis stricta
The Yellow Woodsorrel is a herbaceous plant that grows in woodlands, disturbed areas, and meadows. It is both an annual and perennial weed that has clover-like leaves.
When you look at pictures of weeds, it is easy to spot the plant because it is common in most gardens, and people have used it in salads. However, it also has poisonous parts.
When it blooms, it produces yellow flowers and grows to a maximum height of one foot. It can also spread quickly because the plant grows in all types of soil.
You can eliminate it by hand or dig it up using a hoe. Another option is to use a non-selective herbicide.
In conclusion
The 20 most common weeds and their scientific names are those that grow in backyards, lawns, small gardens, and walkways. Some of them are perennial, and others are annual.
Depending on the characteristics of the plants, you can eliminate them by hand-pulling, digging out, or using a non-selective herbicide.
IW’s Chief Editor and a lover of green spaces.