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.
Acer saccharinum (aka: Silver maple, Soft maple)
Aronia arbutifolia (aka: Red chokeberry)
Acer negundo (aka: Boxelder, Western boxelder, Arizona boxelder, California boxelder, Texas boxelder, Interior boxelder, Violet boxelder)
Salix lucida (aka: Shining willow, Greenleaf willow, Tail-leaf willow, Whiplash willow, Pacific willow, Lance-leaf willow, Longleaf willow, Red willow, Western shining willow)
Salix discolor (aka: Pussy willow, American pussy willow, Glaucous willow, Large pussy willow)
Salix amygdaloides (aka: Peachleaf willow, Peach leaf willow)
Amelanchier arborea (aka: Common serviceberry, Downy serviceberry, Juneberry, Shadbush, Shadblow, Sugarplum)
Acer saccharum (aka: Sugar maple, Rock maple, Hard maple)
Crataegus douglasii (aka: Black hawthorn, Douglas hawthorn, River hawthorn, Western thornapple)
Prunus cerasus (aka: Sour cherry, Tart cherry, Dwarf cherry, Montmorency cherry)
Populus tremuloides (aka: Quaking aspen, Trembling aspen, Aspen, American aspen, Mountain aspen, Golden aspen, Trembling poplar, White poplar, Popple, Alamo Blanco)
Prunus pumila (aka: Sandcherry, Western sandcherry, Eastern sandcherry, Great Lakes sandcherry)
Salix arbusculoides (aka: Littletree willow)
Salix bebbiana (aka: Bebb willow, Beak willow, Beaked willow, Long-beaked willow, Diamond willow, Chaton, Petit Minou, Smooth Bebb willow)
Acer rubrum (aka: Red maple, Scarlet maple)
Malus domestica (aka: Pyrus pumila, Malus pumila, Apple)
Acer platanoides (aka: Norway maple)
Prunus americana (aka: American plum, Goose plum, River plum, Wild plum)
Celtis occidentalis (aka: Common hackberry, Bastard elm, Nettle-tree, Northern hackberry)
Vaccinium angustifolium (aka: Lowbush blueberry, Early low-bush blueberry, Low sweet blueberry)
Rubus canadensis (aka: Smooth blackberry, Thornless blackberry, Canadian blackberry, Smooth highbush blackberry)
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)
Robinia pseudoacacia (aka: Black locust, False acacia, Yellow locust, White locust, Green locust, Post locust, Falsa acacia, Robinia)
Catalpa speciosa (aka: Northern catalpa, Hardy catalpa, Western catalpa, Cigar tree, Catawba-tree, Bois chavanon)
Acer pensylvanicum (aka: Striped maple, Moosewood, Goosefoot maple, Whistlewood)
Acer spicatum (aka: Mountain maple, Low maple, Moose maple, Water maple, Plaine batarde, Fouereux)
Astragalus (aka: Milkvetch, Locoweed, Goat's-thorn)
Salix nigra (aka: Black willow, Swamp willow, Southwestern black willow, Gulf black willow, Scythe-leaved willow)
Salix planifolia (aka: Diamondleaf willow, Planeleaf willow)
Ajuga reptans (aka: Bugle, Blue bugle, Bugleherb, Bugleweed, Carpetweed, Carpet bugleweed, Common bugle, St. Lawrence plant)
Salix alaxensis (aka: Feltleaf willow, Alaska 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)
Aronia melanocarpa (aka: Black chokeberry, Rowan, Mountain Ash, Sorbus)
Prunus pensylvanica (aka: Pin cherry, Fire cherry, Bird cherry)
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)
Prunus serotina (aka: Black cherry, Wild black cherry, Rum cherry, Mountain black cherry, Wild cherry)
Rhamnus cathartica (aka: Common buckthorn, European buckthorn, Dahurian buckthorn)
