Leaf-key
This leaf-key is only meant to supplement the main elimination-key. It is focused on hardwoods (trees with leafs) in the Netherlands. It is not a key you can use on its own, although you are free to try it anyway of course.
This leaf-key has two parts:
1. A part that describes groups of leafs according to characteristics, and then gives links to species of trees that might be what you are looking for. This logical key is below on this page. Each category has a link to a photo page with leafs in that category.
2. Secondly a leaf photo page with examples of all categories with again links to the individual category pages. In addition there is a page with photographs of more species' leafs per photo where you can compare the size a bit. This page is really broadband, since there are tons of data and photos there.
If these two do not let you succeed you can go here to try links to sites with other leaf-keys.
Logical leaf-key.
1. Is the leaf simple (like Oak or Beech) --> go to 5 or compound like a fern --> go to 2.
2. Is the compound leaf like a fern: leafs are opposite to each other -> 3; leafs are alternate on the stem ->4
3. Leafs are arranged opposite to each other: Compound leafs
. The tree is probably one of the next species:
- European mountainash or Sorbus aucuparia (Rosaceae or Rosefamily) |
Black elderberry or Sambucus nigra (Caprifoliaceae)
A species of Ash or (Oleaceae of Olivefamily) |
A species of Leguminosa or Fabaceae
Caucasian wingnut or Pterocarya fraxinifolia |
Common (or black) walnut or Juglans regia
- Sorbus domestica
- Boxelder or Acer negundo
- St. John's Bread Carob or Ceratonia siliqua.
- Kentucky coffeetree or Gymnocladus dioicus
- Mimosa, Silver Wattle or Acacia dealbata
- Heaven tree or Ailanthus altissima
- Horse chestnut or Aesculus hippocastanum |
Red Horse chestnut or Aesculus x carnea = A. hippocastanum x pavia
4. The compound leafs are not in opposite pairs. It is probably one of the next species or genus:
Horse chestnut or Aesculus hippocastanum |
Red Horse chestbut or Aesculus x carnea = A. hippocastanum x pavia
5. Leafs are not compound, but simple, like Beech or Oak. The leafs opposite to each other, on every bud two leafs exactly opposite to each other -> 6; The leafs are not opposite to each other but spring alternately on the twig -> 7.
6. The simple leafs are opposite: Simple leafs facing each other
:
Maple or Acer (Aceraceae of Esdoornfamilie) | Buckthorn or Rhamnus catharticus (not defined here, bush) | Cherry dogwood or Cornus mas (not defined here, bush) | Southern catalpa or Catalpa bignonioides |
Empress tree or Princess tree or Paulownia tomentosa
7. The leafs are simple and not opposite. This group is by far the largest. I will devide this group in categories that are not completely mutually exclusive.
- The leaf is verry narrow and long
(width of a finger) -> Willow genus or Salix (Salicaceae of Willowfamily)
- The leaf is not symmetric, Unequally based leafs, at the base of the leaf one end is longer than the other -> Elm genus or Ulmus (Ulmaceae of Elmfamily)
- The leaf has lobes or "fingers" -> 8;
- The leaf is fairly narrow, but more width than two finger-widths and fairly long (a finger or more 10cm) -> 9
- Still different -> 10
8. Leaf has lobes or "fingers". Lobed leafs:
Oak genus or Quercus (Fagaceae of Beechfamily)
Alder genus or Alnus (Betulaceae of Birchfamily)
Planetree genus or Platanus (Platanaceae of Planetree family)
Grey poplar or Populus canascens |
White poplar or Populus alba |
Aspen or Populus tremula
European filbert or Corylus avellana (Corylaceae)
Turkish filbert or Corylus colurna.
|
Whitebeam | Mountain ash
Sweetgum or Liquidambar styraciflua
Sessile oak or Quercus patrea
Scarlet oak or Quercus cocceinea
Pin oak or Quercus palusrtis
Turkey oak or Quercus cerris
English hawthorn or Crataegus laevigata
White mulberry or Morus alba
Black mulberry or Morus nigra
Ginko biloba
Wild service tree or Sorbus tominalis
Tulip tree or Liriodendron tulpifera
9. The leaf is fairly narrow, but more width than two finger-widths and fairly long (a finger or more 10cm). Elonggated leafs
JapaneseXCaucasian alder or Alnus speathii
Sweet cherry or Prunus avium
Sweet chestnut or Castenanea sativa
Horse chestnut or Aesculus hippocastanum |
Red horse chestnut or Aesculus x carnea = A. hippocastanum x pavia
Walnut or Juglans regia
Medieval Medlar or Mespilus germanica
Cherry laurel or Prunus lauroceratus
southern
magnolia, bull bay or magnolia grandiflora, and tripetala and kobus
Bay laurel
, bay, bay leaf or Laurus nobilis
10. The leaf is simple, not very long, not with obvious lobes or a a-symmetric base. Still some distinctions can be made:
Leaf is fairly small and not heart-shaped, many leafs on the trees are not bigger than 2 euro-coins together -> Birch genus or Betula (Betulaceae of Birchfamily) or
Leaf is heart-shaped -> 11
Non of this -> 12
11. Leaf is heart shaped
:
Linden genus or Tilia (Tliaceae of Lindenfamilie)
Carolina poplar or Populus x canadensis |
Eastern cottonwood; Eastern poplar or Populus deltoides |
Lombardy poplar or Populus nigra Italica | Poplar genus or Populus (Salicaceae of Willowfamily)
Apple or Malus sylvestris
Katsura tree
Pear or Pyrus communis
European filbert or Corylus avellana (Corylaceae)
Italian alder or Alnus cordata
12. Nothing of the kind. Leaf is simple, not very long, not lobed or with fingers, not heart-shaped, not very small. Simple leafs:
Alder genus or Alnus (Betulaceae of Birchfamily)
Cherry with red leafs or Prunus cerasifera 'Nigra'
European Beech or Fagus sylvatica
Turkish filbert or Corylus colurna.
Red European Beech,
Oriental Beech or Fagus Orientalis
Hop hornbeam or Ostrya carpinifolia
European hornbeam; Musclewood; Ironwood or Carpinus betulus
Whitebeam or Sorbus aria
Quince or Cydonia oblonga
Wild Cherry; Black cherry or Prunus serotina
European bird cherry or Prunus Padus
magnolia Southern magnolia, bull bay or magnolia grandiflora, and tripetala and kobus
White mulberry or Morus alba
Black mulberry or Morus nigra
Speckled Alder or Alnus incana
Laurel or Laurus nobilis
Strawberry tree or Arbutus unedo
magnolia
If you haven't found your tree now this key has failed. You can still try the Needles and the like leafs and this photo-graphic page with more species' leafs per photo to find your species.