Well I am not strictly sticking to my A-Z of trees here, but the importance of Guelder Rose in a hedgerow (or in a any garden for that matter) must not go unmentioned.
Despite the ‘rose’ in its name, the guelder rose is not a rose or a tree at all, but a deciduous shrub that is a member of the Moscatel family that includes other viburnums and elders. It’s latin name is Viburnum Opulus. Although a native of the United Kingdom, Northern Africa and Central Asia, the guelder rose takes its name from the Dutch province of Gelderland, where it is known locally as the snowball tree.
Guelder rose is also known as dogberry, water elder, cramp bark, snowball tree, European cranberry bush and in the past, as swamp-elder, which demonstrates its preference for boggy areas.
It is a spreading deciduous shrub with an average growth between 20cm - 40cm per year, reaching up to 4m in height and a spread of 2-5m. This large canopy provides excellent protection for wildlife.
This hedging shrub produces translucent red berries that are eaten by blackbirds, thrushes and finches. The berries are a favourite food of the waxwings that visit the UK from Northern Europe. The flowers of Guelder Rose are especially attractive to hoverflies.
Berries are edible when cooked or made into wine, producing a pleasant acid taste. In Russia, the berries were eaten fresh, added to porridge, baked, made into jams, jellies, marmalades, pastes, mousse, pie fillings, vinegar and condiments. The fruits were also used as a substitute for tea or coffee.
The plant has had many uses in herbal medicine, its primary use is as a muscle relaxant. To this end, the bark been has used to relieve hiccups and pain and spasms in muscles, stomach and intestines. Guelder Rose is naturalised in North America and some native American tribes, such as the Meskwaki tribe used the bark for menstrual cramps, hence the name Cramp Bark.
The Guelder Rose has one main enemy-the viburnum leaf beetle (VLB), Pyrrhalta viburni. This is an invasive insect that feeds exclusively on and can significantly damage Viburnum. The beetle's creamy white larvae cause damage to the leaves in early summer, before pupating in the ground. The adults also feed on the leaves before laying their eggs on the tips of young shoots. Infested twigs can be seen between early October and mid-April.
Several predators feed on viburnum leaf beetle larvae including lady beetle adults and larvae, lacewing larvae and spined soldier bugs nymphs. The lady beetle adults and spined soldier bug adults also eat adult viburnum leaf beetles. The single most effective measure you can take to limit beetle populations is to prune them out. It is best to avoid generalised insecticides as these reduce diversity and can lead to other pest problems.