Not to be semantically confused with : Fragaria [which is the Genus containing the various Strawberry s]
Some similarities to : Buckthorn (Rhamnus cathartica) which is also poisonous but has only four petals which are narrower and longer in shape than the stubby triangular ones of Alder Buckthorn. Alder Buckthorn also lacks the thorns of Buckthorn.
Slight resemblance to : The leaves look similar to those of Dogwood (Cornus sanguinea) and has been mistakenly called Dogwood in the past, but the veins are very different in the path they take through the leaves.
No relation to : Alder [trees with similar names] nor to Buckwheat (Fagopyrum esculentum) nor yo Buck's-Beard (Aruncus dioicus) nor to Sea-Buckthorn (Hippophae rhamnoides) a sea-side shrub.
Some sources leave Alder Buckthorn in the Rhamnus Genus for historical reasons (where it lies along with Buckthorn (Sloe) itself), indeed, both are in the Rhamnaceae family, but a separate Frangula Genus for Alder Buckthorn seems to be widely accepted, being also supported by recent genetic data.
It's name is somewhat of a misnomer for it lacks thorns, but does belong to the same family as Buckthorn (not to be confused with Blackthorn (Prunus spinosa), of sloe fame) which does. However, it has five petals whereas Buckthorn has but four, and its flowers are hermaphroditic (whereas in Buckthorn they are dioecious with mame and female flowers on separate plants).
Some sources say that the shrub has dioecious flowers, with male and female flowers on separate plants, whilst many other sources claim it is bisexual (aka hermaphrodite) where each flower has both male and female parts. Maybe the shrub is a bit ambivalent on this matter. Whatever, the flowers in the above photos of the plant are hermaphroditic.
Charcoal made from the wood of Alder Buckthorn was especially prized for its suitability for making gunpowder and fuses for dynamite because of its even burn-rate.
Native to the UK it originates from Scotland. It obtains its scientific name alnus meaning 'aldes' from because it likes to grow together with Alders in on damp sites.
The Genus name Frangula refers to the brittle nature of the wood. Cultivars are made, Rhamnus frangula 'variegata', 'Tallhedge' for hedging and 'Aslenifolia' with extremely long and narrow leaves, longer even than those of Chinese Weeping Willow .
The bark yields a yellow dye whilst the un-ripe berries produce a green dye which has been used for dying wool. Both berries and bark are poisonous containing a glycosides of poisonous anthraquinones which are purgative, as are those of Purging Buckthorn (Frangula cathartica). The two differently-coloured dyes are derived from these anthraquinones.
USE BY BUTTERFLIES
LAYS EGGS ON |
CATERPILLAR |
CHRYSALIS |
BUTTERFLY |
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Brimstone |
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ANTHRAQUINONES
Alder Buckthorn contains the anthraquinones Aloe-emodin (in the callus but not the bark) and Emodin (aka Frangula-Emodin / Rheum-Emodin).
Chrysophanol and Emodin are orange.
AloeEmodin is orange-yellow
EMODIN GLYCOSIDES
The mono-glycosides of Emodin, called Frangulin A (Emodin-6-O-Rhamnoside) and Frangulin B (Emodin-6_O-Apioside) occur in the bark, the mixture of the two together are known as 'Frangulosid' or 'Frangulin'.
Frangulin is a component of Yellow Lake Pigment (as used by the painters such as Vermeer) which is made from Frangula species. These Lake pigments are very prone to fading by the exposure to light (especially the UV component) over time, and particularly if they are used with chalk rather than aluminium hydroxide as the substrate/absorbent.
Certain anthraquinones, for example Lucidine , can form DNA-adducts with the DNA bases Guanine or Adenine on DNA strands, which result in malfunctional DNA and perhaps cancer.
DIANTHRONES
Within the Frangula genus the bianthrones EmodinDianthrone, ChrysophanolDianthrone and the mixed ChrysophanolEmodinDianthrone are found. The fresh callus predominantly contains the glycosides of ChrysophanolDianthrone and ChrysophanolPhyscionDianthrone .
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