OregonFlora: Balsamorhiza rosea vs. Balsamorhiza

	Balsamorhiza rosea	Balsamorhiza
	rosy balsamroot	balsamroot
Habit		Herbs perennial; with thick, resin-producing taproots.
Stems	5–15 cm, villous-hirsute to villous below heads; from single taproot.	erect, scapose, unbranched.
Leaves	oblong-lanceolate, pinnately lobed from ¼ to ??? to midrib, occasionally some leaves undivided; margins toothed to crenate with pointed teeth; surfaces villous-hirsute; more densely so abaxially than adaxially; basal leaves in 1–few rosettes; blades 2.5–7 × 1.5–2.8 cm; pinnae 6–12 mm wide; petioles 1.5–4.5 cm; cauline leaves in 1 opposite pair or 0; blades 0.7–2 × 0.3–1 cm; petioles 3–4 cm.	mainly basal; simple or pinnately compound, lanceolate to ovate; cauline opposite, sometimes 1 additional pair of reduced cauline leaves alternate.
Inflorescences	with 1 terminal head.	with 1 main head, occasionally with up to 6 axillary heads per stem.
Involucres	10–13 × 20–25 mm.	broadly campanulate to hemispheric.
Receptacles		flat to convex, paleate.
Ray florets	~13, yellow when young, turning from yellow to pink or red; rays 10–15 × 7–8 mm.	pistillate; corollas yellow or rarely pink to red.
Disc florets	~6 mm.	bisexual; corollas yellow, 5-lobed.
Phyllaries	linear to linear-lanceolate, 12–15 × 1–2 cm, villous.	in 2–4 series; outer equaling or surpassing inner.
Fruits	5–6 mm, strigillose.	4-sided; black, glabrous or strigillose; pappi 0.
Heads		radiate.
Paleae	11–13 mm.	lanceolate; acute, folded around fruits.
2n	=38.

	Balsamorhiza rosea	Balsamorhiza
Distribution	[WildflowerSearch map] [BONAP county map]	[BONAP county map]
Discussion	Open, rocky areas. Flowering Apr–May. 300–400 m. Col. WA. Native. Balsamorhiza rosea occurs almost entirely in Washington, with one known locality in Oregon.	Western Canada and United States. 12 species; 10 species treated in Flora. Balsamorhiza is most closely related to Wyethia, from which it is distinguished by being scapose. Balsamorhiza is divided into two sections, both of which occur in Oregon. Section Artorhiza has cordate or sagittate, simple leaves; a taproot bearing multiple crowns; alternate stem leaves above the pair of opposite leaves; and often multiple heads per stem. Section Balsamorhiza has generally pinnately divided leaves (often simple in B. serrata); taproots bearing one or at most two crowns; one pair of opposite stem leaves; and a solitary head per stem. All species of Oregon Balsamorhiza have a chromosome number of n=19 and hybridize when they come together except for the polyploid B. macrophylla. Intersectional hybridization merely produces hybrid swarms, while intrasectional hybridization tends to produce widespread clines, leading to taxonomic confusion. Hybrid swarms are easily distinguished in the field by the wide variation in leaf division and pubescence within a given population. In the herbarium, when only one plant per population is present, hybrids are best distinguished by possessing leaves that are not as deeply divided as would be expected for the most similar-looking member of section Balsamorhiza, or by plants with pinnately divided leaves having either multiple heads per stem or alternate, in addition to opposite, stem leaves. Widths of heads are those of pressed specimens. Widths of pinnae are the width of full-sized pinnae from the middle of a fully developed leaf at their widest point (not including any lobes that may be present).
Source	Flora of Oregon, volume 2, page 200 Abigail (Abby) Moore	Flora of Oregon, volume 1
Sibling taxa	B. careyana, B. deltoidea, B. deltoidea x Balsamorhiza sericea, B. hispidula, B. hookeri, B. incana, B. lanata, B. macrophylla, B. sagittata, B. sericea, B. serrata
Subordinate taxa		B. careyana, B. deltoidea, B. hispidula, B. hookeri, B. incana, B. lanata, B. macrophylla, B. rosea, B. sagittata, B. sericea, B. serrata
Web links	Local floras: OR, WA Local Web sites: 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	Local floras: 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

Balsamorhiza

rosy balsamroot

balsamroot

Habit

Herbs perennial; with thick, resin-producing taproots.

Stems

5–15 cm, villous-hirsute to villous below heads; from single taproot.

erect, scapose, unbranched.

Leaves

oblong-lanceolate, pinnately lobed from ¼ to ??? to midrib, occasionally some leaves undivided;

margins toothed to crenate with pointed teeth;

surfaces villous-hirsute; more densely so abaxially than adaxially;

basal leaves in 1–few rosettes;

blades 2.5–7 × 1.5–2.8 cm;

pinnae 6–12 mm wide;

petioles 1.5–4.5 cm;

cauline leaves in 1 opposite pair or 0;

blades 0.7–2 × 0.3–1 cm;

petioles 3–4 cm.

mainly basal; simple or pinnately compound, lanceolate to ovate;

cauline opposite, sometimes 1 additional pair of reduced cauline leaves alternate.

Inflorescences

with 1 terminal head.

with 1 main head, occasionally with up to 6 axillary heads per stem.

Involucres

10–13 × 20–25 mm.

broadly campanulate to hemispheric.

Receptacles

flat to convex, paleate.

Ray florets

~13, yellow when young, turning from yellow to pink or red;

rays 10–15 × 7–8 mm.

pistillate;

corollas yellow or rarely pink to red.

Disc florets

~6 mm.

bisexual;

corollas yellow, 5-lobed.

Phyllaries

linear to linear-lanceolate, 12–15 × 1–2 cm, villous.

in 2–4 series; outer equaling or surpassing inner.

Fruits

5–6 mm, strigillose.

4-sided; black, glabrous or strigillose;

pappi 0.

Heads

radiate.

Paleae

11–13 mm.

lanceolate; acute, folded around fruits.

=38.

Balsamorhiza

Distribution

[WildflowerSearch map]

[BONAP county map]

Discussion

Open, rocky areas. Flowering Apr–May. 300–400 m. Col. WA. Native.

Balsamorhiza rosea occurs almost entirely in Washington, with one known locality in Oregon.

Western Canada and United States. 12 species; 10 species treated in Flora.

Balsamorhiza is most closely related to Wyethia, from which it is distinguished by being scapose. Balsamorhiza is divided into two sections, both of which occur in Oregon. Section Artorhiza has cordate or sagittate, simple leaves; a taproot bearing multiple crowns; alternate stem leaves above the pair of opposite leaves; and often multiple heads per stem. Section Balsamorhiza has generally pinnately divided leaves (often simple in B. serrata); taproots bearing one or at most two crowns; one pair of opposite stem leaves; and a solitary head per stem. All species of Oregon Balsamorhiza have a chromosome number of n=19 and hybridize when they come together except for the polyploid B. macrophylla. Intersectional hybridization merely produces hybrid swarms, while intrasectional hybridization tends to produce widespread clines, leading to taxonomic confusion. Hybrid swarms are easily distinguished in the field by the wide variation in leaf division and pubescence within a given population. In the herbarium, when only one plant per population is present, hybrids are best distinguished by possessing leaves that are not as deeply divided as would be expected for the most similar-looking member of section Balsamorhiza, or by plants with pinnately divided leaves having either multiple heads per stem or alternate, in addition to opposite, stem leaves. Widths of heads are those of pressed specimens. Widths of pinnae are the width of full-sized pinnae from the middle of a fully developed leaf at their widest point (not including any lobes that may be present).