Trifolium ochroleucon

Ecology

A perennial herb found on chalky boulder-clays or, more rarely, chalk, in pastures and on road verges, trackways and wood-borders. It also occurs as a casual outside its native core area. Lowland.

Status

Native

World Distribution

European Temperate element.

© K.J. Walker, BSBI

Broad Habitats

Light (Ellenberg): 7

Moisture (Ellenberg): 5

Reaction (Ellenberg): 8

Nitrogen (Ellenberg): 2

0

Salt Tolerance (Ellenberg): 0

January Mean Temperature (Celsius): 3.4

July Mean Temperature (Celsius): 16.3

Annual Precipitation (mm): 595

Life form information

Height (cm): 45

Perennation - primary

Perennial

Life Form - primary

Hemicryptophyte

Woodiness

Herbaceous

Clonality - primary

Little or no vegetative spread

Count of 10km squares in Great Britain: 127

Count of 10km squares in Ireland: 0

Count of 10km squares in the Channel Isles: 0

Atlas Change Index: -0.84

Distribution information

JNCC Designations

NHMSYS0000464580

Scarce Atlas Account

Scarce Atlas Account: 

Trifolium ochroleucon Hudson

Sulphur clover

Status: scarce

 

This clover is usually found on the chalky boulder clay, less commonly on chalk, in the lowlands. Most records are from roadside verges or old trackways, less commonly from old pastures and railway embankments and cuttings. As it rarely exceeds 50 centimetres in height it cannot withstand competition from tall grasses such as Calamagrostis epigejos and Festuca arundinacea. It is thus usually associated with shorter mesophytic grasses including Anthoxanthum odoratum, Briza media, Festuca rubra, Helictotrichon pubescens, Lolium perenne, Trisetum flavescens and the sedge Carex flacca. These occur with T. ochroleucon on verges mown in high summer, less commonly in lightly grazed pasture. 

Associated species such as Cirsium acaule, Filipendula vulgaris, Pimpinella saxifraga, Plantago media, Primula veris and Sanguisorba minor indicate calcareous soil, while Betonica officinalis, Lysimachia nummularium, Pulicaria dysenterica, Silaum silaus and Valeriana officinalis suggest seasonally wet soil. Melampyrum cristatum and Pimpinella major are characteristic associates on wood-borders in East Anglia.

T. ochroleucon is a long-lived caespitose perennial. Little is known about its reproductive biology, but it has obviously colonised habitats such as railway cuttings from seed. Many of its old roadside localities have been destroyed in the re-alignment and widening of roads, the use of verges for public utilities such as telephone cables, and the fashion of manicuring verges near farms and villages in the interests of tidiness. T. ochroleucon in England occurs in a predominantly arable landscape, and the relatively few old pastures not ploughed up have usually received dressings of phosphate (as basic slag) and nitrogenous spring dressings which favour the palatable grasses Lolium perenne and Dactylis glomerata at the expense of plants of low competitive ability. Verges left uncut soon develop into tall (1.8 metres) stands of Festuca arundinacea and other coarse grasses: their mattress of dead leaves allows few associates to survive.

T. ochroleucon is fairly widespread in western, southern and central Europe, predominantly on clay soils. It extends eastwards to Iran and is also recorded from North Africa.

 

D. E. Coombe

PLANTATT - Attributes of British and Irish plants. (.zip 1455KB) This dataset was compiled and published in 2004, and last updated in November 2008. Download includes an Excel spreadsheet of the attributes, and a PDF explaining the background and nomenclature. Note that the PDF version is the booklet as published, whereas the Excel spreadsheet incorporates subsequent corrections. A hardcopy can be purchased from the Centre for Ecology and Hydrology.

Atlas text references

Atlas (105b)
Flora dels Països Catalans, I. Introducció. Licopodiàcies-Capparàcies,
de Bolòs, O., and Vigo J.
, Barcelona, (1984)

Scarce plants in Britain,
Stewart, A., Pearman D. A., and Preston C. D.
, Peterborough, (1994)