Ulex minor

Tracheophyta MagnoliopsidaFabaceaeUlexUlex minor

Ecology

A small, sometimes procumbent shrub of heaths on free-draining acidic, nutrient-poor soils over podsolised sands and gravels, and occasionally over superficial deposits overlying chalk. In heathland areas it can persist as an under-storey shrub in scrub and secondary woodland. It also occurs on undergrazed heathy pastures and, rarely, on wet heaths. Lowland.

Status

Native

World Distribution

Oceanic Southern-temperate element.

Broad Habitats

Dwarf shrub heath (cover of dwarf shrubs at least 25%)

Light (Ellenberg): 8

Moisture (Ellenberg): 6

Reaction (Ellenberg): 1

Nitrogen (Ellenberg): 2

Salt Tolerance (Ellenberg): 0

January Mean Temperature (Celsius): 3.9

July Mean Temperature (Celsius): 16.4

Annual Precipitation (mm): 745

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: 197

Count of 10km squares in Ireland: 0

Count of 10km squares in the Channel Isles: 4

Atlas Change Index: 0.2

JNCC Designations

NBNSYS0000003213

Scarce Atlas Account

Scarce Atlas Account: 

Ulex minor Roth

Dwarf gorse

Status: not scarce

 

This shrub is locally frequent in dry or somewhat moist Calluna vulgaris-Erica cinerea heath, occurring locally with Agrostis curtisii and/or Molinia caerulea, on acid, nutrient-poor soils on podzolised sands and gravels. These soils are mainly of Cretaceous (Wealden, Lower Greensand) or Tertiary (Eocene, Oligocene) age, but U. minor is also a component of `chalk heaths' on thin superficial deposits overlying chalk, and occurs in heaths on sandy glacial drift in the East Midlands. It occurs locally along heathy roadsides and rides in acid woodland, perhaps always a relic of pre-existing heath. It is a palatable species which is suppressed by heavy grazing. U. minor has a similar (but narrower) ecological niche to U. gallii, which replaces U. minor in western and northern Britain. The boundary between the distributions of the two species is remarkably sharp, with little geographical overlap. U. europaeus differs from both in being primarily a plant of heath margins, acid grassland and scrub, generally on acid brown-earth soils rather than heath podzols. U. minor grows from near sea-level to c. 240 metres altitude at Hindhead. 

It is a low spiny shrub, reproducing entirely by seed, and generally flowering and fruiting freely every year. The seeds are hard-coated and germination tends to be slow and erratic, but seedling establishment takes place readily, especially after fire.

The map show that there has been little decline in the overall distribution of this species; the pre-1970 records in Sussex are due to the lack of recent recording of a locally common species. It has, however, been lost from many sites over the last half century owing to the destruction of heathland by agriculture, forestry, building and industrial development, and the spread of scrub and woodland when tree growth is no longer prevented by grazing or burning.

U. minor occurs in central and western France, northern, north-western and south-western Spain, and Portugal.

U. minor is often confused with U. gallii. Both are very plastic, especially in the size of vegetative parts, and show parallel ranges of variation. Populations of U. minor generally have a mean calyx length less than 9 mm and, in low-growing heathland plants, often 8 mm or less. U. gallii populations usually have a mean calyx length of more than 10 mm and even starved populations on thin soils rarely have a mean calyx length as short as 9 mm (Proctor 1965).

 

M. C. F. Proctor

Atlas text references

Atlas (101a)
Proctor MCF
1965.  The distinguishing characters and geographical distributions of Ulex minor and Ulex gallii. Watsonia. 6:177-187.
Stewart A, Pearman DA, Preston CD
1994.  Scarce plants in Britain.