According to observations of naturalists and beekeepers.
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It is an herbaceous flowering plant, in the mint family, native to Europe. It is invasive in parts of North America. Grown as a garden plant it provides useful groundcover.
This plant is present in at least 38 states/provinces in this country.
Ajuga reptans is a sprawling perennial herb with erect flowering stems and grows to a height of about 10 to 35 cm (4 to 14 in).
The stems are squarish with hairs on two sides and the plant has runners that spread across the surface of the ground.
The purplish-green, stalked leaves are in opposite pairs.
The leaf blades are hairless and are elliptical or ovate with a rounded tip and shallowly rounded teeth on the margin.
The inflorescence forms a dense raceme and is composed of whorls of blue flowers, each with dark veins on the lower lip. The calyx has five toothed lobes and the corolla forms a two-lipped flower about 14 to 17 mm (0.6 to 0.7 in) long with a short tube. The upper lip of each flower is short and flat with a smooth edge and the lower lip is three-lobed, the central lobe being the largest, flat with a notched tip. There are four stamens, two long and two short, which are longer than the corolla and are attached to the tube. The ovary is superior and the fruit is a schizocarp with four chambers.
Bloom Time: May to June
Brassica napus (aka: Rapeseed)
Allium schoenoprasum (aka: Chives)
Sinapis arvensis (aka: Charlock mustard, California rape, Charlock, Corn mustard, Canola, Kaber mustard, Rapeseed mustard)
Asclepias tuberosa (aka: Butterflyweed, Butterfly Milkweed, Orange Milkweed, Pleurisy Root, Chigger Flower, Canada root, Fluxroot, Indian paintbrush, Indian posy, Orange root, Orange Swallow-wort, Tuber root, Yellow milkweed, White-root, Windroot, Butterfly love)
Cirsium arvense (aka: Creeping Thistle, Canada thistle, Field thistle, California thistle, Lettuce from hell thistle, Corn thistle, Cursed thistle, Green thistle, Hard thistle, Perennial thistle, Prickly thistle, Small-flowered thistle, Way thistle, Stinger-needles)
Chamaenerion angustifolium (aka: Fireweed, Great willowherb, Rosebay willowherb, Saint Anthony's Laurel, French-willow)
Citrullus lanatus (aka: Watermelon)