OregonFlora: Balsamorhiza macrophylla vs. Balsamorhiza lanata

	Balsamorhiza macrophylla	Balsamorhiza lanata
	large-leaf balsamroot	woolly balsamroot, Yreka balsamroot
Stems	up to 35 cm, tomentose; from single taproot.
Leaves	lanceolate-oblong, 1-pinnately divided; pinnae toothed, with teeth only on lower margins; surfaces tomentose; basal leaves in 1–few rosettes; blades 12–22 × 6–8 cm; pinnae 10–36 mm wide; petioles 7–20 cm; cauline blades 1.5–5 × 0.3–0.9 cm; petioles 6–9 cm.
Inflorescences	with 1 terminal head.
Involucres	14–18 × 25–30 mm.
Ray florets	14–16, yellow; rays 35–40 × 8–11 mm.
Disc florets	~9 mm.
Phyllaries	ovate-lanceolate, 20–25 × 5–6 mm; tips acuminate, tomentose.
Fruits	8–9 mm, glabrous.
Paleae	10–12 mm.
2n	=100 ± 2.

	Balsamorhiza macrophylla	Balsamorhiza lanata
Distribution	[WildflowerSearch map] [BONAP county map]	[BONAP county map]
Discussion	Dry, open areas. Flowering May–Jul. 700–1400 m. BW. ID; east to WY. Native. True B. macrophylla is a decaploid centered on the Wasatch Mountains in Utah and Idaho. The plants in Oregon and western Idaho are also high polyploids, but they differ morphologically from classic B. macrophylla in their denser pubescence and the shape of their leaves. These eastern plants have been given the name B. macrophylla var. idahoensis. However, further study will likely show that they have a different parentage than B. macrophylla s.s. The specific epithet “macrophylla” means large-leaved, as the leaves are much larger than those of the other members of section Balsamorhiza.
Source	Flora of Oregon, volume 2, page 200 Abigail (Abby) Moore
Sibling taxa	B. careyana, B. deltoidea, B. deltoidea x Balsamorhiza sericea, B. hispidula, B. hookeri, B. incana, B. lanata, B. rosea, B. sagittata, B. sericea, B. serrata	B. careyana, B. deltoidea, B. deltoidea x Balsamorhiza sericea, B. hispidula, B. hookeri, B. incana, B. macrophylla, B. rosea, B. sagittata, B. sericea, B. serrata
Synonyms	Balsamorhiza hookeri var. idahoensis	Balsamorhiza hookeri var. lanata
Web links	Local floras: OR 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: CA, OR Local Web sites: CalFlora, CalPhotos, 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

Balsamorhiza lanata

large-leaf balsamroot

woolly balsamroot, Yreka balsamroot

Stems

up to 35 cm, tomentose; from single taproot.

Leaves

lanceolate-oblong, 1-pinnately divided;

pinnae toothed, with teeth only on lower margins;

surfaces tomentose;

basal leaves in 1–few rosettes;

blades 12–22 × 6–8 cm;

pinnae 10–36 mm wide;

petioles 7–20 cm;

cauline blades 1.5–5 × 0.3–0.9 cm;

petioles 6–9 cm.

Inflorescences

with 1 terminal head.

Involucres

14–18 × 25–30 mm.

Ray florets

14–16, yellow;

rays 35–40 × 8–11 mm.

Disc florets

~9 mm.

Phyllaries

ovate-lanceolate, 20–25 × 5–6 mm;

tips acuminate, tomentose.

Fruits

8–9 mm, glabrous.

Paleae

10–12 mm.

=100 ± 2.

Balsamorhiza lanata

Distribution

[WildflowerSearch map]

[BONAP county map]

Discussion

Dry, open areas. Flowering May–Jul. 700–1400 m. BW. ID; east to WY. Native.

True B. macrophylla is a decaploid centered on the Wasatch Mountains in Utah and Idaho. The plants in Oregon and western Idaho are also high polyploids, but they differ morphologically from classic B. macrophylla in their denser pubescence and the shape of their leaves. These eastern plants have been given the name B. macrophylla var. idahoensis. However, further study will likely show that they have a different parentage than B. macrophylla s.s. The specific epithet “macrophylla” means large-leaved, as the leaves are much larger than those of the other members of section Balsamorhiza.

Source

Flora of Oregon, volume 2, page 200
Abigail (Abby) Moore

Sibling taxa