No relation to :
Hazel (which belongs to the Corylus Genus, a member of the Birch (Betulaceae Family)) [a tree with similar name] - but the leaves are similar.
Not to be semantically confused with : Wych Elm (Ulmus glabra) which is another tree belonging to the Elm (Ulmus genus, nor with Witch's Broom a gall on some trees.
Can be artificially hybridised with :
Japanese Witch-Hazel to produce Hamamelis intermedia, from which numerous different cultivars are produced.
Some similarities to : Cornelian Cherry (Cornus Mas) which is also a tree bearing yellow, 4-petalled flowers in January well before the leaves.
Lookee-Likees : many other
Uniquely identifiable characteristics
Distinguishing Feature (of Witch-Hazels) : The four long, narrow, linear petals emerging from stalk-less flowers which grow at shortish intervals along the twigs and branches.
Witch-Hazel trees are cultivated. They are not native and most have to be grown by grafting onto the rootstock of another
Witch-Hazel, usually Hamamelis virginiana. There are many hybrids, Intermediate Witch-Hazel being but one which is derived from the hybrid between Chinese Witch-Hazel and Japanese Witch-Hazel Hamamelis japonica. They are not very common, for the grafting process means their cost is high.
Being cultivated does not prevent them spreading, however, which they do only by suckering, especially if the graft happens to be below ground level. Chinese Witch-Hazel is the more decorative of other previous cultivated varieties (such as Hamamelis virginiana), and flowers earlier before the leaves, which otherwise partially obscure the flowers on these preceding varieties of Witch-Hazel.
It has a high proportion of tannins, both hamamelitannins and gallotannins, which are toxic to the kidneys and the liver. It also contains catechols and proanthocyanidins. It has anti-inflammatory and astringent properties. The Hamamelitannin shown is based upon a central unit of
D-Ribose to which are attached two identical
Galloyl units (3,4,5-trihydroxybenzoate).
The essential oil, of which the tree can supply very little, contains Hexenol, α-Ionone, β-Ionone,
Safrole (aka Shikimol) and traces of Eugenol, Carvacrol and some sesquiterpenes.
Witch Hazel is better known for the steam distillate that can be produced from it in greater quantities than can the essential oil. The steam distillate is used medicinally (externally) as a styptic to stem blood flow from an external wound. The steam distillate lacks the tannins but has the same volatiles as the essential oil together with a spicy aroma.
Safrole (aka Shikimol) is a phenylpropene and is a slightly yellow oily liquid that is found in the fruit and root-bark of the
Sassafras plants (which are not native to the UK) from which 'root-beer' or Sarsaparilla cordial is produced, and which once included Safrole as an ingredient. Safrole itself is poisonous and now has to be removed from any oils intended for human consumption. Safrole also occurs in a number of spices such as
Black Pepper and in herbs such as
Basil. Safrole used to be included in some soaps as a fragrance, but that use too is now banned.
α-Ionone is one of the Rose Ketones so named because they are found in essential oils of
Roses, as well as in the essential oils of some other plants.. There are three Ionones,
α-Ionone, β-Ionone, and
γ-Ionone, all having the same skeletal shape, but with the double bond in differing places. All are aroma compounds used in perfumery, and are degradation products of the Carotenoids.