Betula nana L.

ISFS : 60300
Checklist : 1006590


Species description (© Flora Helvetica 2018)

Niedriges Sträuchlein, nicht über 1 m hoch. Jüngste Triebe dicht flaumig behaart, ohne Harzdrüsen. Blätter nur 4-12 mm lang, kahl, rundlich, oft breiter als lang, mit stumpfen Zähnen. Männliche und weibliche Blütenstände abstehend oder aufrecht, höchstens 1 cm lang. Fruchtflügel schmal.

Flowering period (© Flora Helvetica 2018)


Habitat and distribution inside Switzerland (© Flora Helvetica 2018)

Torfmoore / montan / J (nördlich bis JU), vereinzelt AN und M

World distribution (© Flora Helvetica 2018)


Ecological indicator (© Flora Helvetica 2018)



IUCN status


National Priority

 3 - medium national priority

International responsibility

 2 - medium

Distribution map


Before threshold year
After threshold year
Before and after threshold year


Validated observations
Observations waiting for validation
Occurrences from Atlas Welten & Sutter (1982) and supplements (1984, 1994) without confirmation in the Info Flora database since
Before threshold year
After threshold year
Not native / introduced / subspontaneous / escaped

Number of observations

Below the threshold number of observations
Above or equal the threshold number of observations

Habitat and distribution inside Switzerland

J (nördlich bis JU), vereinzelt AN und M

World distribution



Life form



Habitats © Delarze & al. 2015

Character species 2.4.1 - Offene Hochmoore (Sphagnion magellanici)
Less strictly linked to a specific habitat 6.5.2 - Hochmoor-Bergföhrenwald (Ledo-Pinion)

bold Dominant species, influencing the appearance of the habitat
Character species Character species
Less strictly linked to a specific habitat Less strictly linked to a specific habitat

Ecological indicator values by © Landolt & al. (2010)

Soil factors Climatic factors Salinity tolerance
Humidity Value H 5w Light Value L 4 Salinity Index --
Reaction Value R 1 Temperature factor T 3
Nutriments value N 1 Continentality K 2
  • Ecological values legend
    Humidity Value H
    1very dry
    2moderatly dry
    3medium wet
    4very wet
    5submerged or underwater
    fplants living in running water
    umostly submerged plants
    vpartly submerged, partly floating plants
    whumidity moderately variable (± scale of 1-2)
    w+highly variable humidity (scale exceeding ± 2)
    Reaction Value R
    1Very acid (pH 2.5-5.5)
    2acid (pH 3.5-6.5)
    3lightly acid to neutral (pH 4.5-7.5)
    4neutral to basic (pH 5.5-8.5)
    5basic (pH 6-5 -> 8.5
    Nutriments value N
    1very low in nutrients
    2low in nutriments
    3medium-poor to medium-rich in nutrients
    4rich in nutriments
    5very rich in nutriments
    Salinity tolerance
    Light Value L
    1very shady
    3lighted areas
    5highly luminous
    Temperature factor T
    1alpine to nival stages (from the treeline to the snowline)
    1+suprasubalpine and upper subalpine levels (pine and larch forests)
    2subalpine level (coniferous forests without beeches up to the upper limit of spruces)
    2+lower subalpine and upper mountain stages
    3mountain level (beech and silver fir forests, in the central Alps Scots pine forests)
    3+lower mountain and upper hill levels
    4hill level (mixed deciduous oak forests)
    4+hot places, hill level
    5very hot places, hill level (only in the hottest places, typical of southern Europe)
    Continentality K
    1Atlantic (high air humidity, very low temperature variations, mild winters)
    2Sub-Atlantic (high air humidity, low temperature variations, relatively mild winters)
    3sub-Atlantic to subcontinental (average air humidity, moderately variable temperature, slightly low winter temperatures)
    4subcontinental (low air humidity, large temperature variations, rather cold winters)
    5continental (very low air humidity, very large temperature variations, cold winters)

Water dependency

Rivers 0 - No link
Calm water 1 - Secondary habitat
Ground water 0 - No link


Accepted Name (Checklist 2017)

Betula nana L.

Vernacular name

Deutscher Name :


Nom français :

Bouleau nain

Nome italiano :

Betulla nana

Match with other reference books

Relation Nom Book No
=Betula nana L.Checklist 201760300
=Betula nana L.Flora Helvetica 2001256
=Betula nana L.Flora Helvetica 2012338
=Betula nana L.Flora Helvetica 2018338
=Betula nana L.Index synonymique 199660300
=Betula nana L.Landolt 1977826
=Betula nana L.Landolt 1991727
=Betula nana L.SISF/ISFS 260300
=Betula nana L.Welten & Sutter 1982132
= The taxon corresponds to the accepted taxon (Checklist 2017)
< The taxon is included in the accepted taxon (Checklist 2017)
> The taxon includes (among others) also the accepted taxon (Checklist 2017)


Native status


IUCN list of endangered species (© Walter & Gillett 1997) : No

Status on national Red List 2016

IUCN status:



Additional information

IUCN criteria: A4c; C2a(i)

Status on regional Red List 2019

Biogregraphic regions Status IUCN criteria
Jura (JU) VUA4c; C2a(i)
Mittelland (MP) CRA4c; C2a(i)
Alpennordflanke (NA) CRA4c; C2a(i)
Alpensüdflanke (SA) --
Östliche Zentralalpen (EA) --
Westliche Zentralalpen (WA) --
  • Legend
    RERegionally Extinct
    CR(PE)Critically Endangered, Probably Extinct
    CRCritically Endangered
    NTNear Threatened
    LCLeast Concern
    DDData Deficient
    NENot Evaluated
    NANot Applicable

National Priority Species List Status

National Priority 3 - medium national priority
Need to take action 1 -
International responsibility 2 - medium
Need to monitor populations 1 -

Protection status

International (Bern Convention) No
OWtotal protection (01.04.2013)
SZtotal protection (24.09.1992)
VDtotal protection (02.03.2005)
Switzerland --
ZHpartial protection (03.12.1964)
SGtotal protection ( flowering) (01.10.2017)
AItotal protection (13.03.1989)
  • Disclaimer
    InfoFlora compiles information on protected species as accurately as possible, taking it from the respective cantonal laws. In some cases, however, it was not possible to use the plant names as listed in the original text, but an interpretation of their taxonomy or nomenclature was necessary. The exact meaning of the categories „completely protected“ and „partially protected“ differs among the cantons.

    InfoFlora cannot guarantee that the information on the protection status is correct and complete. In case of doubts, we recommend to look up the texts of the respective cantonal law.


Threats and measures

In-situ measures

More informations

B. U. Schwarz und P. Poschlod, 2015: Die Letzten ihrer Art in Bayern - Das Eiszeitrelikt Zwergbirke (Betula nana L.), ANLIEGEN NATUR 37(1): 19-30J. Guyonneau et Y. Ferrez, 2005: Connaissance de la flore rare ou menacée de Franche-Comté, Betula nana L., Conservatoire botanique de Franche-Comté, 10 p.