Weed Identification: 15 Common Unwelcome Weeds
Even with the best-laid plans, it’s hard to control your outdoor spaces. Those ideal growing conditions that you work so hard to cultivate for your landscaping plants are also fertile ground for the wild plants we call “weeds.” The following is a list of some of the most common invaders of gardens and yards.
Hairy crabgrass (Digitaria sanguinalis) is a plant species that is known worldwide as a common weed. In certain circumstances, Hairy crabgrass is used as animal fodder. This grass species is extremely hardy and almost always requires a detailed control plan, as any chemicals used to eliminate it may also harm surrounding grasses.
While native to Europe, the Common plantain was one of the first plants to reach North America through early European explorers. Native Americans have referred to Plantago major as ‘white mans footprint’, as it disrupted many local ecosystems by its introduction.
Field bindweed (Convolvulus arvensis) is a native Eurasian plant related to morning glory. It is considered an invasive species in non-native areas because it competes with other plants for sunlight and moisture. Field bindweed is very hard to eradicate because its taproots grow so deep and its seeds can remain viable for decades.
Rumex crispus, commonly known as Curly dock, is a perennial plant that grows in temperate regions of the northern hemisphere. It is a very adaptable plant, flourishing in a variety of different habitats including roadsides, the edges of woodlands, meadows, and shorelines. Some moth species like to lay their eggs on Curly dock leaves.
Field horsetail (Equisetum arvense) grows from moist soils. In the spring it generates brown, non-photosynthetic stems whose whole purpose is to release reproductive spores. Once those stems wither, the plant grows its sterile photosynthetic stem to harvest and store energy for the next growing season. The plant fibers are slightly abrasive, and in the past were used to polish pewter and wooden objects. Ironically, Field horsetail is toxic to horses and other livestock.
Ground ivy (Glechoma hederacea) is a perennial evergreen trailing plant, often found in grasslands and woodlands. Saxon peoples once spread the plant, but it has become invasive in some parts of the world now. The fast-growing Ground ivy can be toxic to horses but generally cannot harm other animals or humans.
White clover (Trifolium repens) is a perennial herb, one of the most cultivated species of clover. It can be found on lawns and grasslands all over the world. White clover is often cultivated as a forage plant and used for green manure in agriculture.
Taraxacum officinale, widely known as Common dandelion is a herbaceous perennial that can be found in temperate regions all over the world, in habitats with moisty soils. The most popular feature of this plant are its fruits – furry spheres that are easily carried by the wind. Although it is generally considered a weed, Common dandelion is actually edible and very nutritious.
Portulaca oleracea, colloquially known as Common purslane, is an annual succulent species with reddish stems and tiny yellow, five-petal flowers. It is used for culinary purposes in various parts of the world, most often raw, in salads. Common purslane is also a good companion plant for crops that thrive in moist soils.
Poison sumac (Toxicodendron vernix) is a woody shrub whose oil causes an itchy, burning rash. It’s considered more allergenic than poison ivy and poison oak. The sap from this plant is sometimes used to make a black varnish for woodworking.
Although the Common nettle has a variety of uses it is best known for its eponymous sting. It has sharp defensive hairs on its leaves and stems which will release pain-inducing chemicals when touched. Nevertheless, Dorset, England hosts an annual World Nettle Eating Championship, which started with a debate between two farmers over the severity of their nettle infestations. To consume them more safely, Common nettle must be thoroughly boiled.
Chameleon plant (Houttuynia cordata) is a perennial low-growing shrub. In spring, its leaves burst forth with a kaleidoscopic mix of red, green, and white coloration. The name “chameleon” references the plant’s colorful nature. In summer, beautiful white flowers with bristle-like centers bloom. Chameleon plant is common in Vietnamese and Chinese cuisine.
Annual ragweed (Ambrosia artemisiifolia) is one of the most notorious weeds in the world. It is an annual herbaceous plant with highly allergenic pollen and a very vigorous spread. Annual ragweed is a very competitive species, which is why its presence in cultivated plants is highly undesirable.
Celastrus orbiculatus is a vine that grows and spreads aggressively and has been deemed an invasive species in many areas. Oriental bittersweet is an opportunistic climber and climbs any available tree or structure. The vine wraps around itself as it climbs, and has been known to completely strangle or girdle a mature host tree.
Hearing the name of Japanese knotweed can strike fear in the heart of homeowners. When this aggressive and invasive weed is identified on a property, mortgage lenders sometimes deny loans or demand extensive chemical treatment. This is due to the fact that the root system of Japanese knotweed is so extensive that once established, it can be nearly impossible to eradicate.