OregonFlora: Vaccinium uliginosum vs. Vaccinium myrtillus

	Vaccinium uliginosum	Vaccinium myrtillus
	bog bilberry, bog blueberry	whortleberry
Habit	Shrubs deciduous, 0.2–0.7 m, in dense mats; stems round in cross section; twigs round in cross section to angled, green to grayish brown, glabrous to finely puberulent, older twigs slightly peeling; rhizomatous.	Shrubs deciduous, up to 4 dm; branching habit open, rarely weakly “broom-like”; twigs strongly angled, green to greenish brown, sparsely puberulent along grooves, sometimes glabrous; rhizomatous.
Leaves	ovate to elliptic, 9–29 × 4–18 mm; thin or thick at maturity; margins entire; tips rounded to acute; surfaces abaxially glabrous or glaucous, adaxially glabrous.	elliptic to ovate, 11–20(30) × 5–10 mm, light green abaxially, green adaxially; thin; flexible; margins sharply serrate from tips to near base, prominently veined; tips acute; surfaces abaxially glandular, adaxially glabrous.
Inflorescences	racemes, 2–4-flowered, occasionally 1-flowered.	solitary flowers in axils.
Flowers	distinct; sepals 4 or 5, usually glaucous; corollas urceolate, 4–6 × 2–5 mm, white to pink, glaucous; petals 4 or 5; filaments ? anthers, glabrous.	sepals 5; calyces shallowly lobed, glabrous; petals 5; corollas ovoid-urceolate to globose, 3–7 × 4–7 mm, white to pink, glaucous; filaments glabrous.
Fruits	4–9 mm in diameter, blue to bluish black, with a faint bloom.	4–9 mm in diameter, dark red to bluish black; without a bloom.
2n	=24, 48, 72.	=24, 48.

	Vaccinium uliginosum	Vaccinium myrtillus
Distribution	[WildflowerSearch map] [BONAP county map]	[WildflowerSearch map] [BONAP county map]
Discussion	Wet mid-elevation montane and coastal habitats. Flowering May–Sep. 0–2400 m. BW, Casc, ECas, Est, Sisk. CA, ID, NV, WA; northern US and Canada; Asia, Europe. Native. Some authorities consider the coastal form of V. uliginosum a distinct species (V. occidentale). If recognized, this species would be identified by its distinctly reticulated leaf veins, thin leaves, and smaller fruits.	Wet mid- to high elevation areas. Flowering Apr–Jul. 1100–2100 m. BW, Casc, Sisk. ID, NV, WA; northeast to Alberta and southeast to NM, Greenland; Asia, Europe. Native. Morphologically, Vaccinium myrtillus is similar to V. scoparium, and at higher elevations their ranges overlap. Vaccinium myrtillus differs from V. scoparium by its generally larger leaves and flowers, often sparsely puberulent twigs, and its broom-like habit.
Source	Flora of Oregon, volume 2, page 642 Stephen Meyers	Flora of Oregon, volume 2, page 640 Stephen Meyers
Sibling taxa	V. caespitosum, V. corymbosum, V. deliciosum, V. macrocarpon, V. membranaceum, V. myrtillus, V. ovalifolium, V. ovatum, V. oxycoccos, V. parvifolium, V. scoparium	V. caespitosum, V. corymbosum, V. deliciosum, V. macrocarpon, V. membranaceum, V. ovalifolium, V. ovatum, V. oxycoccos, V. parvifolium, V. scoparium, V. uliginosum
Synonyms	Vaccinium occidentale, Vaccinium uliginosum ssp. occidentale, Vaccinium uliginosum var. alpinum, Vaccinium uliginosum var. uliginosum
Web links	Local floras: BC, OR, WA Local Web sites: Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search	Local floras: BC, OR, WA Local Web sites: Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Vaccinium myrtillus

bog bilberry, bog blueberry

whortleberry

Habit

Shrubs deciduous, 0.2–0.7 m, in dense mats; stems round in cross section; twigs round in cross section to angled, green to grayish brown, glabrous to finely puberulent, older twigs slightly peeling; rhizomatous.

Shrubs deciduous, up to 4 dm; branching habit open, rarely weakly “broom-like”; twigs strongly angled, green to greenish brown, sparsely puberulent along grooves, sometimes glabrous; rhizomatous.

Leaves

ovate to elliptic, 9–29 × 4–18 mm; thin or thick at maturity;

margins entire;

tips rounded to acute;

surfaces abaxially glabrous or glaucous, adaxially glabrous.

elliptic to ovate, 11–20(30) × 5–10 mm, light green abaxially, green adaxially; thin; flexible;

margins sharply serrate from tips to near base, prominently veined;

tips acute;

surfaces abaxially glandular, adaxially glabrous.

Inflorescences

racemes, 2–4-flowered, occasionally 1-flowered.

solitary flowers in axils.

Flowers

distinct;

sepals 4 or 5, usually glaucous;

corollas urceolate, 4–6 × 2–5 mm, white to pink, glaucous;

petals 4 or 5;

filaments ? anthers, glabrous.

sepals 5;

calyces shallowly lobed, glabrous;

petals 5;

corollas ovoid-urceolate to globose, 3–7 × 4–7 mm, white to pink, glaucous;

filaments glabrous.

Fruits

4–9 mm in diameter, blue to bluish black, with a faint bloom.

4–9 mm in diameter, dark red to bluish black; without a bloom.

=24, 48, 72.

=24, 48.

Vaccinium uliginosum

Vaccinium myrtillus

Distribution

[WildflowerSearch map]

[BONAP county map]

[WildflowerSearch map]

[BONAP county map]

Discussion

Wet mid-elevation montane and coastal habitats. Flowering May–Sep. 0–2400 m. BW, Casc, ECas, Est, Sisk. CA, ID, NV, WA; northern US and Canada; Asia, Europe. Native.

Some authorities consider the coastal form of V. uliginosum a distinct species (V. occidentale). If recognized, this species would be identified by its distinctly reticulated leaf veins, thin leaves, and smaller fruits.

Wet mid- to high elevation areas. Flowering Apr–Jul. 1100–2100 m. BW, Casc, Sisk. ID, NV, WA; northeast to Alberta and southeast to NM, Greenland; Asia, Europe. Native.

Morphologically, Vaccinium myrtillus is similar to V. scoparium, and at higher elevations their ranges overlap. Vaccinium myrtillus differs from V. scoparium by its generally larger leaves and flowers, often sparsely puberulent twigs, and its broom-like habit.

Source

Flora of Oregon, volume 2, page 642
Stephen Meyers

Flora of Oregon, volume 2, page 640
Stephen Meyers

Sibling taxa