Ellenberg - Light

The requirements of a species for light are summarised by Ellenberg L values, as follows.

 

Ellenberg value

Explanation

1

Plant in deep shade (no examples for Britain or Ireland)

2

Between 1 and 3 (Epipogium aphyllum, Neottia nidus-avis, Trichomanes speciosum)

3

Shade plant, mostly less than 5% relative illumination, seldom more than 30% illumination when trees are in full leaf (Galium odoratum, Listera cordata, Mercurialis perennis)

4

Between 3 and 5 (Circaea lutetiana, Lamiastrum galeobdolum, Poa nemoralis)

5

Semi-shade plant, rarely in full light, but generally with more than 10% relative illumination when trees are in leaf (Carex pendula, Hyacinthoides non-scripta, Primula vulgaris)

6

Between 5 and 7 (Anthriscus sylvestris, Digitalis purpurea, Teucrium scorodonia)

7

Plant generally in well lit places, but also occurring in partial shade (Arrhenatherum elatius, Carex flacca, Poa trivialis, Vicia cracca)

8

Light-loving plant rarely found where relative illumination in summer is less than 40% (Cardamine hirsuta, Orchis morio, Thymus polytrichus, Vaccinium oxycoccus)

9

Plant in full light, found mostly in full sun (Aster tripolium, Melilotus albus, Poa compressa, Primula farinosa)