Montana Field Guide

Stems 1–2 m, pilose, becoming brown, glabrous. Leaf blades 2–8 cm long, glabrous, paler beneath, serrate on the upper half. Inflorescence a conical, pilose panicle 4–20 cm long. Flowers: sepals hairy to glabrous, 0.5 mm long; petals pink or rose, ca. 1.5 mm long. Follicles 2–3 mm long (Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX).

Pyramidal Spiraea is a natural hybrid between Spiraea douglasii var. menziesii and Spiraea betulifolia var. lucida, which are all present in Montana.

Douglas Spirea – Spiraea douglasii, native:
* Inflorescence is cone-shaped, at least three times longer than broad.
* Flowers are pink to rose.
* Montana’s variety is menziesii.

Pyramidal Spiraea – Spiraea x pyramidata, native hybrid:
* Inflorescence is cone-shaped, about as long as broad or up to twice as long as broad.
* Flowers are pink-tinged.

White Spirea – Spiraea betulifolia, native:
* Inflorescence is flat-topped to hemispheric, broader than long.
* Flowers are white.
* Leaves are glabrous.
* Montana’s variety is lucida.

Rose Meadowsweet – Spiraea splendens, native:
* Inflorescence is flat-topped to hemispheric, broader than long.
* Flowers are rose.
* Leaves are hairy on the margins.

Source: Lesica et al. (2012).

Thickets, wet meadows, usually along streams, wetlands; valleys (Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX).

POLLINATORS
The following animal species have been reported as pollinators of this plant species or its genus where their geographic ranges overlap: Bombus vagans, Bombus auricomus, Bombus fervidus, Bombus nevadensis, Bombus ternarius, Bombus griseocollis, and Bombus impatiens (Macior 1968, Heinrich 1976, Colla and Dumesh 2010, Colla et al. 2011, Koch et al. 2012).