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Heuchera merriamii

Canyon Creek alumroot, Merriam's alumroot

alumroot, American alum-root, common alum-root

Habit Herbs acaulescent; caudex branched or unbranched. Herbs acaulescent; caudex branched.
Flowering stems

11–32 cm, long stipitate-glandular or glabrate.

leafy, 40–145 cm, glabrous or short stipitate-glandular.

Leaves

petiole (2.4–5 cm), moderately long stipitate-glandular;

blade orbiculate, reniform, or pentagonal, shallowly 5–7-lobed, 2.5–4.5 cm, base shallowly cordate to truncate, lobes rounded, margins dentate, apex rounded to obtuse, surfaces finely long stipitate-glandular abaxially, sparsely long stipitate-glandular adaxially.

petiole glabrous or very short to long stipitate-glandular;

blade (often variegated adaxially), broadly ovate to cordate, shallowly 5–9-lobed, 3.5–11 cm, base cordate to nearly truncate, lobes rounded or ovate, margins dentate, apex acute or obtuse, surfaces abaxially glabrous or short stipitate-glandular, adaxially glabrous or short stipitate-glandular.

Inflorescences

dense; (bracts linear and scarious to 3–5-parted and herbaceous).

diffuse.

Flowers

hypanthium radially symmetric, free 0.5–1.5 mm, pink, hemispheric, 3–5.5 mm, (base rounded), densely long stipitate-glandular;

sepals erect, green- or red-tipped, equal, 1–2 mm (often wider than long), apex obtuse;

petals erect, white, oblanceolate, (clawed), unlobed, 2–3.5 mm, margins entire;

stamens exserted 0.8–2 mm;

styles exserted 1–2 mm, 1.5–2.5 mm, 0.1+ mm diam.

hypanthium weakly bilaterally symmetric, free 0.6–2 mm, green, urceolate or campanulate, abruptly inflated distal to adnation to ovary, 3–7.2 mm, very short stipitate-glandular;

sepals erect, green-tipped, equal, 1–2.4 mm, apex rounded;

petals erect, greenish, white, pink, or purple, narrowly spatulate, unlobed, 0.9–4 mm, margins entire or finely dentate or fimbriate;

stamens exserted 3–5 mm;

styles exserted 2.6–6.4 mm, 4–7 mm, to 0.1 mm diam.

Capsules

ovoid, 3–5 mm, beaks divergent, not papillose.

ovoid, 4–10.5 mm, beaks divergent, not papillose.

Seeds

dark brown, ellipsoid, 0.6 mm.

dark brown, ellipsoid, 0.6–0.9 mm.

2n

= 14.

Heuchera merriamii

Heuchera americana

Phenology Flowering Jul–Aug.
Habitat Exposed granite ledges in subalpine forests
Elevation 1500-2500 m (4900-8200 ft)
Distribution
from FNA
CA; OR
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; AR; CT; DE; GA; IL; IN; KY; LA; MD; MI; MO; MS; NC; NJ; NY; OH; OK; PA; SC; TN; VA; WV; ON
[WildflowerSearch map]
[BONAP county map]
Discussion

Heuchera merriamii is known from the Siskiyou and Trinity mountains.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Varieties 3 (3 in the flora).

Heuchera americana is highly polymorphic and distributed over a large part of the eastern United States and Canada. Its variability is largely the result of its wide geographic range, the sporadic, semi-isolated distribution of populations, and interaction of differential adaptation and genetic drift made possible by its distribution pattern.

Heuchera americana intergrades with both H. pubescens and H. richardsonii where they overlap; the intergrading form with H. pubescens is H. americana var. hispida, and with H. richardsonii it is H. americana var. hirsuticaulis. A breeding study between H. americana, H. pubescens, H. richardsonii, and other species demonstrated ease of artificial hybridization and fertility of offspring among H. americana, H. pubescens, and H. richardsonii (E. F. Wells 1979).

Individuals of the three varieties do not form intermixed populations; populations tend to be geographically isolated from one another and to be relatively uniform, displaying somewhat narrow character variation within a population.

The Cherokee Indians took Heuchera americana for dysentery and used the powdered root for malignant ulcers, bad sores, bowel complaints, piles, female problems, and sore mouth. The Chickasaw Indians used the root as an astringent and tonic (D. E. Moerman 1998).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Key
1. Petioles densely long stipitate-glandular.
var. hirsuticaulis
1. Petioles glabrous or short to sparsely long stipitate-glandular
→ 2
2. Petioles glabrous or very short to sparsely long stipitate-glandular; hypanthia free 0.6-1.5 mm; petals greenish, white, or pink, narrower than sepals, margins entire or finely dentate.
var. americana
2. Petioles glabrous or very short stipitate-glandular; hypanthia free 1.5-2 mm; petals purple or pink, wider than sepals, margins fimbriate.
var. hispida
Source FNA vol. 8, p. 93. FNA vol. 8, p. 94.
Parent taxa Saxifragaceae > Heuchera Saxifragaceae > Heuchera
Sibling taxa
H. abramsii, H. alba, H. americana, H. bracteata, H. brevistaminea, H. caespitosa, H. caroliniana, H. chlorantha, H. cylindrica, H. eastwoodiae, H. elegans, H. glabra, H. glomerulata, H. grossulariifolia, H. hallii, H. hirsutissima, H. longiflora, H. maxima, H. micrantha, H. novamexicana, H. parishii, H. parviflora, H. parvifolia, H. pilosissima, H. pubescens, H. pulchella, H. richardsonii, H. rubescens, H. sanguinea, H. villosa, H. wootonii
H. abramsii, H. alba, H. bracteata, H. brevistaminea, H. caespitosa, H. caroliniana, H. chlorantha, H. cylindrica, H. eastwoodiae, H. elegans, H. glabra, H. glomerulata, H. grossulariifolia, H. hallii, H. hirsutissima, H. longiflora, H. maxima, H. merriamii, H. micrantha, H. novamexicana, H. parishii, H. parviflora, H. parvifolia, H. pilosissima, H. pubescens, H. pulchella, H. richardsonii, H. rubescens, H. sanguinea, H. villosa, H. wootonii
Subordinate taxa
H. americana var. americana, H. americana var. hirsuticaulis, H. americana var. hispida
Name authority Eastwood: Bull. Torrey Bot. Club 32: 199. 1905 (as merriami), Linnaeus: Sp. Pl. 1: 226. 1753 ,
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