Cornus rugosa Lam. — Roundleaf dogwood

Introduction

Roundleaf dogwood is a deciduous shrub of cool eastern North American forests, thickets, rocky slopes, and stream or lake margins. Its broad, almost round leaves and pale blue to bluish-white fruit give it a distinctive appearance among the North American members of Subgenus Thelycrania (Murrell & Poindexter 2016; Deasy et al. 2026).

The species participates naturally in hybridization where ranges overlap. Crosses with gray dogwood (C. racemosa) are named C. × friedlanderi, while crosses with red-osier dogwood (C. sericea) are C. × slavinii. These named hybrids are best interpreted as evidence of gene flow, not as reasons to erase the parental species.

Horticultural and Agricultural Uses

Roundleaf dogwood is less common in horticulture than red-osier or gray dogwood, but it can be an effective native shrub for cool woodland-edge gardens. The rounded foliage, broad white flower clusters, and blue-tinged fruit provide a quiet ornamental character, while its native ecology favors reasonably moist soils and cool summers (Deasy et al. 2026).

Where restoration rather than ornamental display is the goal, locally sourced material is preferable. Its natural hybridization with other dogwoods also means that seed collected in contact zones may not breed true to the parent species.

Conservation Concerns

The species is broadly secure across much of its native range and is treated as Least Concern in modern dendrological summaries. Local losses can follow forest conversion or shoreline development, but there is no indication of an immediate global extinction threat. Maintaining regional populations also preserves the contact zones that generate its named hybrids.

Additional Information

iNaturalist (opens in a new tab) - Direct taxon page with community observations.
Trees and Shrubs Online (opens in a new tab) - Detailed morphology, ecology, cultivation, and hybrid context.
Plants of the World Online (opens in a new tab) - Accepted backbone, distribution, and synonymy.
Flora of North America (opens in a new tab) - Regional taxonomic and ecological treatment.

References and Further Reading

Deasy M, Crowley D, Aldridge J, Chişu R (2026) Cornus rugosa. Trees and Shrubs Online. https://www.treesandshrubsonline.org/articles/cornus/cornus-rugosa/ (opens in a new tab)

Royal Botanic Gardens, Kew (2026) Cornus rugosa Lam.. Plants of the World Online. https://powo.science.kew.org/results?q=Cornus%20rugosa%20Lam (opens in a new tab)

Murrell ZE, Poindexter DB (2016) Cornaceae. In: Flora of North America Editorial Committee (eds) Flora of North America North of Mexico, vol. 12. Oxford University Press, New York and Oxford. https://www.efloras.org/flora_page.aspx?flora_id=1 (opens in a new tab)