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
Salix lucida (aka: Shining willow, Greenleaf willow, Tail-leaf willow, Whiplash willow, Pacific willow, Lance-leaf willow, Longleaf willow, Red willow, Western shining willow)
Liriodendron tulipifera (aka: Tuliptree, Blue-poplar, Tulip-poplar, Yellow-poplar, Yellow wood)
Prunus pumila (aka: Sandcherry, Western sandcherry, Eastern sandcherry, Great Lakes sandcherry)
Salix bebbiana (aka: Bebb willow, Beak willow, Beaked willow, Long-beaked willow, Diamond willow, Chaton, Petit Minou, Smooth Bebb willow)
Acer platanoides (aka: Norway maple)
Catalpa speciosa (aka: Northern catalpa, Hardy catalpa, Western catalpa, Cigar tree, Catawba-tree, Bois chavanon)
Prunus americana (aka: American plum, Goose plum, River plum, Wild plum)
Viburnum prunifolium (aka: Blackhaw, Black haw, Blackhaw viburnum, Sweet haw, Stag bush, Smooth Blackhaw Viburnum, Stagbush, Viburnum bushii)
Rhamnus cathartica (aka: Common buckthorn, European buckthorn, Dahurian buckthorn)
Robinia pseudoacacia (aka: Black locust, False acacia, Yellow locust, White locust, Green locust, Post locust, Falsa acacia, Robinia)
Vaccinium angustifolium (aka: Lowbush blueberry, Early low-bush blueberry, Low sweet blueberry)
Rubus laciniatus (aka: Cutleaf blackberry, Evergreen blackberry, Slashed blackberry)
Rubus phoenicolasius (aka: Wine raspberry, Japanese wineberry, Wineberry)
Ajuga reptans (aka: Bugle, Blue bugle, Bugleherb, Bugleweed, Carpetweed, Carpet bugleweed, Common bugle, St. Lawrence plant)
Malus ioensis (aka: Bechel crab, Crab apple, Iowa crab, Iowa crab apple, Prairie crab, Prairie crab apple)
Astragalus (aka: Milkvetch, Locoweed, Goat's-thorn)
Rubus idaeus (aka: Raspberry, Black-haired red raspberry, Brilliant red raspberry, American red raspberry, Red raspberry, Smoothleaf red raspberry, Wild raspberry, Wild red raspberry, Grayleaf raspberry)
Rhus glabra (aka: Smooth sumac, Common sumac, Rocky Mountain sumac, Red sumac, Western sumac, White sumac)
Brassica napus (aka: Rapeseed)
Allium schoenoprasum (aka: Chives)
Sinapis arvensis (aka: Charlock mustard, California rape, Charlock, Corn mustard, Canola, Kaber mustard, Rapeseed mustard)
Gleditsia triacanthos (aka: Honey locust, Honey shucks locust, Common honeylocust, Sweet bean locust)
Aronia melanocarpa (aka: Black chokeberry, Rowan, Mountain Ash, Sorbus)
Prunus serotina (aka: Black cherry, Wild black cherry, Rum cherry, Mountain black cherry, Wild cherry)
Prunus pensylvanica (aka: Pin cherry, Fire cherry, Bird cherry)
Vaccinium corymbosum (aka: Highbush blueberry, High-bush blueberry, Northern highbush blueberry, Tall blueberry, Rabbiteye blueberry, Blue huckleberry, Tall huckleberry, Swamp huckleberry, High blueberry, Swamp blueberry)
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)
Tilia americana (aka: American basswood, Basswood, Linden)
Amorpha fruticosa (aka: Desert false indigo, False indigo-bush, Bastard indigobush, Indigo Bush)
Asclepias syriaca (aka: Сommon milkweed, Butterfly flower, Silkweed, Silky swallow-wort, Virginia silkweed)
Salsola kali (aka: Russian thistle, Tumbleweed, Prickly saltwort)
Brassica rapa (aka: Field mustard, Common mustard, Wild mustard, Wild turnip, Forage turnip, Wild rutabaga, Birdsrape mustard, Rape mustard)
Echium vulgare (aka: Viper's bugloss, Blueweed, Blue thistle)
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)
Prunus virginiana (aka: Chokecherry, Western chokecherry, Common chokecherry, Black chokecherry)
Diervilla lonicera (aka: Northern bush honeysuckle, Bush-honeysuckle, Dwarf bush-honeysuckle, Herbe bleue)