Salix lapponum

Tracheophyta MagnoliopsidaSalicaceaeSalixSalix lapponum

Ecology

A low shrub of moist or wet, moderately base-enriched sites on rocky mountain slopes and cliffs. This species tolerates a wider range of soil conditions than most montane Salix, but is now largely confined to cliffs. From 210 m (Ochil Hills, W. Perth) to 1000 m (Aonach Beag, Westerness).

Status

Native

World Distribution

Eurosiberian Boreo-arctic Montane element.

Broad Habitats

Montane habitats (acid grassland and heath with montane species)

Light (Ellenberg): 8

Moisture (Ellenberg): 6

Reaction (Ellenberg): 6

Nitrogen (Ellenberg): 3

Salt Tolerance (Ellenberg): 0

January Mean Temperature (Celsius): 0.2

July Mean Temperature (Celsius): 11.3

Annual Precipitation (mm): 1956

Height (cm): 100

Perennation - primary

Perennial

Life Form - primary

Nanophanerophyte

Woodiness

Woody

Clonality - primary

Little or no vegetative spread

Count of 10km squares in Great Britain: 101

Count of 10km squares in Ireland: 0

Count of 10km squares in the Channel Isles: 0

Atlas Change Index: -0.73

JNCC Designations

NBNSYS0000003880

Scarce Atlas Account

Scarce Atlas Account: 

Salix lapponum L.

Downy willow

Status: scarce

 

This is a shrub of moist to wet, enriched sites on mountains. It tolerates a wider range of soil conditions than most other montane willows, but its natural range and habitat preferences are masked by the pressure of grazing, which confines S. lapponum largely to cliffs or rocky sites. Associated species are many but often include Deschampsia cespitosa, Luzula sylvatica, S. myrsinifolia or S. phylicifolia and Vaccinium myrtillus. On base-rich sites it can occur with rarer montane willows such as S. lanata and, on ungrazed ledges, with tall herbs such as Geranium sylvaticum and Solidago virgaurea. It grows at altitudes from 200 metres in the Ochils to 900 metres at Coire Garbhlach. 

Seed is produced in quantity in colonies with numerous male and female plants, and significant reproduction by seed can occur on sites with regular landslips and rockfalls. However, at many sites plants are too isolated for effective pollination to occur (Mardon 1990) and few if any seeds are produced. But, as seedlings require predominantly bare soil and freedom from competition in order to establish (Meikle 1975), few will develop under stable conditions. Where such stable conditions develop, the ground stratum may provide a good medium for vegetative spread.

At many of the montane sites on which S. lapponum can survive, with protection from grazing, the natural instability results in progressive loss of plants. Small colonies or isolated plants produce little or no seed and are unable to reproduce. Such colonies observed regularly appear to be in steady decline (Mardon 1990). However, data are not available to demonstrate that a clear decline in range has taken place.

S. lapponum is a Eurasian species which is widely distributed in Scandinavia, northern Russia, and Siberia, but rare in central France, the Pyrenees, central Europe, the Balkans and southern Russia. In the Alps it is replaced by the closely related S. helvetica Vill. For a map of the European distribution of S. lapponum, see Jalas & Suominen (1976).

 

D. K. Mardon

Atlas text references

Atlas (190d)
Bean WJ
1980.  Trees and shrubs hardy in the British Isles, edn 8, IV. Ri-Z.
Hultén E, Fries M
1986.  Atlas of north European vascular plants north of the Tropic of Cancer. 3 vols.
Jalas & Suominen (1976)
Mardon DK
1990.  Conservation of montane willow scrub in Scotland. Transactions of the Botanical Society of Edinburgh. 45:427-436.
Meikle RD
1984.  Willows and poplars of Great Britain and Ireland. Botanical Society of the British Isles Handbook no. 4.
Meusel H, Jäger E, Weinert E
1965.  Vergleichende Chorologie der zentraleuropäischen Flora. Volume 1. 2 vols.
Stewart A, Pearman DA, Preston CD
1994.  Scarce plants in Britain.