Glechoma hederacea is an aromatic, perennial, evergreen creeper of the mint family Lamiaceae. It is commonly known as ground-ivy, gill-over-the-ground, creeping charlie, alehoof, tunhoof, catsfoot, field balm, and run-away-robin. It is also sometimes known as creeping jenny, but that name more commonly refers to Lysimachia nummularia. It is used as a salad green in many countries. European settlers carried it around the world, and it has become a well-established introduced and naturalized plant in a wide variety of localities. It is also considered an aggressive invasive weed of woodlands and lawns in some parts of North America. In the absence of any biological control, research conducted by the USDA herbicides are relied upon particularly for woodland ecosystems. The plant's extensive root system makes it difficult to eradicate by hand-pulling.
Glechoma hederacea
Flower's appearance in visible, UVA, and NIR spectrums. The UV nectar guides may help attract bees.
G. hederacea seedling - cot = cotyledons; ga = axillary bud, from (Warming 1884)
Image: Glechoma hederacea, Hondsdraf (1)
A weed is a plant considered undesirable in a particular situation, growing where it conflicts with human preferences, needs, or goals. Plants with characteristics that make them hazardous, aesthetically unappealing, difficult to control in managed environments, or otherwise unwanted in farm land, orchards, gardens, lawns, parks, recreational spaces, residential and industrial areas, may all be considered weeds. The concept of weeds is particularly significant in agriculture, where the presence of weeds in fields used to grow crops may cause major losses in yields. Invasive species, plants introduced to an environment where their presence negatively impacts the overall functioning and biodiversity of the ecosystem, may also sometimes be considered weeds.
Weeds growing in the cracks of a concrete staircase (Epilobium roseum, Chelidonium majus, Oxalis corniculata, Plantago major)
A dandelion is a common plant all over the world, especially in Europe, Asia, and the Americas. It is considered a weed in some contexts (such as lawns) but not others (such as when it is grown as a vegetable or herbal medicine).
Invasive Canada Goldenrod as a roadside weed in Poland
Australia, 1907: Cattlemen survey 700 carcasses of cattle that were killed overnight by a poisonous plant.