OregonFlora: Vaccinium myrtillus vs. Vaccinium scoparium

	Vaccinium myrtillus	Vaccinium scoparium
	whortleberry	grouseberry, grouse whortleberry
Habit	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.	Shrubs deciduous, up to 4 dm; branching habit crowded, giving a “broom-like” appearance; twigs strongly angled, green to yellowish green, glabrous; rhizomatous.
Leaves	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.	elliptic to ovate-lanceolate, 7–15 × 4–14 mm, light green abaxially, green adaxially; thin; flexible; margins finely serrate from tips to near base, prominently veined; tips acute; surfaces abaxially often glandular, adaxially glabrous.
Inflorescences	solitary flowers in axils.	solitary flowers in axils.
Flowers	sepals 5; calyces shallowly lobed, glabrous; petals 5; corollas ovoid-urceolate to globose, 3–7 × 4–7 mm, white to pink, glaucous; filaments glabrous.	sepals 5; calyces very shallowly lobed, glabrous; petals 5; corollas urceolate to globose, 3–4 × 3–5 mm, pink, glaucous; filaments glabrous.
Fruits	4–9 mm in diameter, dark red to bluish black; without a bloom.	3–6 mm in diameter, bright red to bluish purple; without a bloom.
2n	=24, 48.	=24.

	Vaccinium myrtillus	Vaccinium scoparium
Distribution	[WildflowerSearch map] [BONAP county map]	[WildflowerSearch map] [BONAP county map]
Discussion	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.	Subalpine and alpine meadows, slopes and pine forests. Flowering May–Aug. 1000–2700 m. BR, BW, Casc, CR, ECas, Sisk. CA, ID, NV, WA; northeast to Alberta, east to SD, southeast to NM. Native. See also V. myrtillus.
Source	Flora of Oregon, volume 2, page 640 Stephen Meyers	Flora of Oregon, volume 2, page 641 Stephen Meyers
Sibling taxa	V. caespitosum, V. corymbosum, V. deliciosum, V. macrocarpon, V. membranaceum, V. ovalifolium, V. ovatum, V. oxycoccos, V. parvifolium, V. scoparium, V. uliginosum	V. caespitosum, V. corymbosum, V. deliciosum, V. macrocarpon, V. membranaceum, V. myrtillus, V. ovalifolium, V. ovatum, V. oxycoccos, V. parvifolium, V. 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, CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria, Turner Photog. WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Vaccinium scoparium

whortleberry

grouseberry, grouse whortleberry

Habit

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.

Shrubs deciduous, up to 4 dm; branching habit crowded, giving a “broom-like” appearance; twigs strongly angled, green to yellowish green, glabrous; rhizomatous.

Leaves

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.

elliptic to ovate-lanceolate, 7–15 × 4–14 mm, light green abaxially, green adaxially; thin; flexible;

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

tips acute;

surfaces abaxially often glandular, adaxially glabrous.

Inflorescences

solitary flowers in axils.

Flowers

sepals 5;

calyces shallowly lobed, glabrous;

petals 5;

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

filaments glabrous.

sepals 5;

calyces very shallowly lobed, glabrous;

petals 5;

corollas urceolate to globose, 3–4 × 3–5 mm, pink, glaucous;

filaments glabrous.

Fruits

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

3–6 mm in diameter, bright red to bluish purple; without a bloom.

=24, 48.

=24.

Vaccinium scoparium

Distribution

[WildflowerSearch map]

[BONAP county map]

[WildflowerSearch map]

[BONAP county map]

Discussion

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.

Subalpine and alpine meadows, slopes and pine forests. Flowering May–Aug. 1000–2700 m. BR, BW, Casc, CR, ECas, Sisk. CA, ID, NV, WA; northeast to Alberta, east to SD, southeast to NM. Native.

See also V. myrtillus.

Source

Flora of Oregon, volume 2, page 640
Stephen Meyers

Flora of Oregon, volume 2, page 641
Stephen Meyers

Sibling taxa