According to observations of naturalists and beekeepers.
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Calluna vulgaris (common heather, ling, or simply heather) is the sole species in the genus Calluna in the flowering plant family Ericaceae. It is naturalized in North America from Newfoundland west to Michigan and south through Nova Scotia and the New England states to the mountains of West Virginia. It is widespread throughout Europe.
This plant is present in at least 17 states/provinces in this country.
Heather is an evergreen ascending shrub, usually reaching 3.3 feet (1 m) in height. Growth form varies from low and sparse to dense and bushy. The opposite leaves are 0.08 to 0.16 inches (0.2-0.4 cm) long, and flowers are in axillary or terminal racemes. The root system is lateral and mostly buried within the top 4 inches (10 cm) of soil. On poorly drained sites, roots may extend to 8inches (20 cm) below ground. Young plants have a taproot that is later obscured by increased growth and branching of lateral roots. A surface mat is formed by adventitious roots and fine branches of the main root system.
In North America heather flowers from July to November.
Salix bebbiana (aka: Bebb willow, Beak willow, Beaked willow, Long-beaked willow, Diamond willow, Chaton, Petit Minou, Smooth Bebb willow)
Rhus glabra (aka: Smooth sumac, Common sumac, Rocky Mountain sumac, Red sumac, Western sumac, White sumac)
Allium schoenoprasum (aka: Chives)
Brassica napus (aka: Rapeseed)
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)
Calendula officinalis (aka: Marigold, Calendula, Pot marigold, English marigold)
Asclepias syriaca (aka: Сommon milkweed, Butterfly flower, Silkweed, Silky swallow-wort, Virginia silkweed)
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)
Agastache foeniculum (aka: Giant hyssop, Blue giant hyssop, Anise hyssop, Fragrant giant hyssop, Lavender giant hyssop)
Cucumis melo (aka: Cantaloupe, Rockmelon, Sweet melon, Spanspek, Honeydew melon, Honeymelon, Crenshaw, Casaba)
Citrullus lanatus (aka: Watermelon)
Borago officinalis (aka: Borage, Starflower, Common borage, Cool-tankard, Tailwort)
Diervilla lonicera (aka: Northern bush honeysuckle, Bush-honeysuckle, Dwarf bush-honeysuckle, Herbe bleue)
Cephalanthus occidentalis (aka: Common buttonbush, Buttonball, Buttonbush, Button willow, Riverbush, Honey-bells)
Hyssopus officinalis (aka: Hyssop)
Calluna vulgaris (aka: Heather, Scotch heather, Common heather, Ling, Simply heather)
Allium tuberosum (aka: Garlic chives, Oriental garlic, Asian chives, Chinese chives, Chinese leek)