Viburnum opulus – Guelder rose
The Guelder rose is another stunning member of the beautiful honeysuckle family. Often seen growing as an ornamental, like many of its close relatives, this shrub delightfully adorns our hedges and country lanes up and down the land. You can go foraging for both its medicinal bark in the spring, and the edible berries in autumn.
The first time you clap eyes on this plant may be during their lovely spring time show. The immaculate white flowers penetrate dense green canopies adjourning our lanes around May. Later in the year, the berries will brighten up increasingly dull grey days with splashes of scarlet in amongst yellowing autumn hedgerows.
Favourite habitats of Guelder rose.
Closely related to the elder tree, this shrub is almost entirely absent in Scotland, yet can be found most everywhere in England. It delights in copses of Alnus (alder) and Salix (willow), as well as in a range of hedges, woodland edges, bridleways, and country lanes up to elevations of 400 metres.
Guelder rose is said to be well suited to chalk land. Because cramp bark displays similar growth characteristics to the elder, it has also historically been known as ‘red elder’ and ‘rose elder’.
This deciduous, perennial shrub is native to Europe, North Africa and Northern Asia. It can easily grow up to 4 metres high on many stems. Cramp bark can flourish in full sun or partial shade and will tolerate most soils other than very wet ones. When planting this species, the advice has always been to avoid extremely hot or dry, exposed, and cold areas.
The other well known common name for this plant stems from the province of Holland known as Gueldersland. This is where the shrub was first recorded as being cultivated. The generic name Viburnum is the old Latin name for this shrub and others in the genus of about 150-175 mainly shrubby species. The specific name opulus refers to a type of maple, in allusion to the maple-like leaf shape of this species.
Distinctive features of Guelder rose
This plant’s most noticeable features are the distinctive umbel-like inflorescence and subsequent clusters of scarlet berry fruits. The almost flat-topped, dense corymb is typically around 11 cm wide and snow-white coloured, gracing our hedgerows from May-July ( with our recent warmer springs here in Britain they are increasingly out in the south during May).
The flowers of Guelder rose are conspicuous in the way that they produce large (15-20 mm wide) sterile outer flowers, surrounding much smaller (6 mm wide) fertile flowers which eventually give rise to the fruits. These will then ripen in drooping clusters and are ready from September-October.
The branches have grey twigs, somewhat angular in shape. These carry opposite pairs of buds and leaves, mainly terminating with double buds.
The buds are scaly, and appear thin when viewed from one side, but reasonably broad and becoming tapered when viewed from the other. The twigs carry a similarity in colour and form to the elder, especially the opposite pairs of buds.
Learn more about the patterns of plants, and how they can fast track your foraging, in my article here.
When foraging Guelder rose, you will see the leaves are somewhat akin to a maple. They are often broader than long, usually deeply-divided into 3-5 lobes, and with toothed margins. The leaves are sometimes voraciously eaten to a lacy outline by the viburnum leaf beetle (Pyrrhalta viburni). It is not unusual to find some plants decimated by this insect in certain areas.
Here’s what Mrs Grieves’ online herbal, says about Guelder rose.
Parts used: Inner bark. Berries
Harvest: Bark from 3-5 year old branches in early spring before leaf break. Berries in autumn.
Key constituents: Salicin (which converts to salicylate in the body); isovalerianic acid; sesquiterpenes (viopudial, viburtinal); catechin tannins; coumarin (scopoletin); bitter principle (viburtine).
Actions: Anti-spasmodic, anti-inflammatory, nervine, tonic, astringent, diuretic.
Pharmacology and uses: As its name suggests, this plant has long been used to alleviate painful cramps and spasms.
In North America a closely related species, black haw (V.prunifolium), is often used interchangeably, although they have slightly different chemical constituents. Certain indigenous North American Indian tribes such as the Meskwaki and the Penobscot reportedly used cramp bark for muscle swellings and mumps.
The famed ‘cramp bark’ of Guelder rose works by relieving and relaxing tense muscles, whether these are skeletal such as back muscles and limbs, or internal smooth muscles such as the intestines, airways, ovaries or uterus.
On another page on the website, you can discover more about the actions of medicinal plant constituents, as well as learning more about the plant meadowsweet, from where salicylic acid was extracted to make the popular drug, aspirin
Cramp bark can also be taken internally as a decoction or applied topically. It has long been used to treat breathing difficulties in asthma as well as menstrual pains associated with excessive uterine contractions. Some authors have noted it as being useful where miscarriage is threatened. Cramp bark is also helpful in cases of irritable bowel syndrome, colic, and the physical symptoms of nervous tension.
The molecule salicin, upon digestion, converts to salicylic acid. As a known anti-inflammatory, it will heal and support internal smooth muscles.
This plant also has value in treating cardio-vascular hypertension and is known to relieve constipation associated with tension. Read more on the cardio-vascular system here. The anti-spasmodic action is known to be conferred in part by the substance valerianic acid.
In some cases of arthritis, where joint weakness and pain have forced muscles to contract until almost rigid, cramp bark can be usefully employed and can bring often remarkable relief. This is because as the muscles relax, more blood can flow, metabolic waste products such as lactic acid can be removed and some degree of normal function can return.
Cramp bark can therefore be used in acute and chronic cases of muscle pains and cramps. It can also be usefully used before embarking on any physical activity likely to bring pain.
The berries are not used medicinally. Some authors class them as poisonous whilst others mention them as edible. Tasted straight of the tree they are very bitter due to the substance viburtine.
The berries have been known to cause gastroenteritis when consumed raw. But cooking with the addition of sugar can make a nice enough preserve, but personally I prefer other fruit jams to this one.
Using the bark of Guelder rose is safe and effective for long and short term use, although maybe not if the patient is on anti-coagulant medications. This is because the coumarins and salicylates are both known to thin the blood.
The plant has been reported to cause hypotension in large doses or even in average doses if taken by previously hypotensive individuals. Pregnant women ought to refrain from taking the bark of Guelder rose until they have consulted a qualified practitioner.
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