Alnus cordata (Italian Alder)

Plate 1 figs. a–h · 8 separate observations

Alnus cordata, photographed by Stephen James McWilliam — fig. a Stephen James McWilliam, CC0 1.0 / 2022-05-05 / obs. 195085067

Alnus cordata, photographed by Jon Mortin — fig. c Jon Mortin, CC BY 4.0 / obs. 194663778

Alnus cordata, photographed by Daniel Cahen — fig. d Daniel Cahen, CC BY 4.0 / obs. 171305482

Every figure is a research-grade observation under CC0, CC BY or CC BY-SA, rehosted with the photographer’s name, the licence and the observation it came from. Photographs under a NonCommercial licence are excluded from this site and are never stored, which costs us a great many pictures and is not negotiable.

Native range 3 botanical countries

Native distribution of Alnus cordata, after Kew’s World Checklist of Vascular Plants. Introduced, extinct and doubtful records are excluded, so this is where the plant is from, not everywhere it now grows.

Region	TDWG code	Continent
Albania	ALB	EUROPE
Corse	COR
Italy	ITA

Region boundaries approximated from Natural Earth (public domain) and mapped to TDWG World Geographical Scheme for Recording Plant Distributions (WGSRPD) level-3 botanical countries (Brummitt 2001). Indicative, not the official WGSRPD geometry.

Where it actually grows measured, from 1,417 observations

Condition	5th percentile	Median	95th percentile
Coldest month, mean daily low	-1.9 °C	1.7 °C	4.6 °C
Warmest month, mean daily high	17.7 °C	20.3 °C	27.1 °C
Annual rainfall	637 mm	882 mm	1,411 mm
Rainfall in the driest quarter	103 mm	165 mm	249 mm

It is found where winters bring light frost. This is not care advice and it is not a forecast. It is a measurement: we sampled the climate at every one of the 1,417 research-grade observations of Alnus cordata that carry a coordinate, and this is the range those places actually span. The 5th and 95th percentiles are used rather than the minimum and maximum, because a single cultivated specimen in a heated conservatory should not widen a tropical plant's range to the Arctic.

This is not a hardiness zone. A USDA zone is the average annual extreme minimum temperature. The figure above is the mean daily minimum of the coldest month, which is a different quantity and is typically far warmer. Reading one as the other would place a plant several zones too warm, so we do not publish a hardiness zone, because we do not have one.

Also published as 11 synonyms

A synonym is not an error. It is a record of botanists disagreeing, in print, about where this plant belongs. Each of these was somebody’s considered answer.

Alnus cordata Desf.
Alnus cordata f. parvifolia Callier
Alnus cordata var. rotundifolia Dippel
Alnus cordifolia Ten.
Alnus cordifolia var. rotundifolia Regel
Alnus macrocarpa Req. ex Nyman
Alnus neapolitana Savi
Alnus nervosa Dippel
Alnus obcordata C.A.Mey. ex Steud.
Alnus rotundifolia Bertol.
Betula cordata Loisel.

Sourcesevery claim on this page

World Flora Online Plant List. accepted name, authority, classification. CC0. Retrieved 2026-07-12.
iNaturalist. photographs and flowering annotations, CC0 / CC BY / CC BY-SA only. per photograph. Retrieved 2026-06-27.
Wikidata. common name (P1843), joined on the World Flora Online identifier (P7715). CC0. Retrieved 2026-07-13.
Kew, World Checklist of Vascular Plants (WCVP v16). native distribution by TDWG level-3 botanical country, and life form. CC BY 3.0. Retrieved 2026-06-04.

We publish what we can source and we say so when we cannot. This page has no care advice and no toxicity claim, because we do not yet have those from a source we can cite.