It just used to include the willows, poplar, aspen, and cottonwoods.
Genetic studies summarized by the Angiosperm Phylogeny Group (APG) have greatly expanded the circumscription of the family to contain 56 genera and about 1220 species, including the Scyphostegiaceae and many of the former Flacourtiaceae.
BUT; fortunately for us, in the British Isles it has only two main genera, namely the Poplar and the Willow. Although the flowers (as always in traditional classification) determine the ultimate genus and whether it is a Willow or Poplar, most of us can easily tell the difference from the leaves. All the Poplars have a triangular, broad oval, to heart-shape outline with often a long leaf stem (petiole) whilst most of the Willows have long, narrow leaves or roundish, much smaller leaves than Poplars.
When there are no leaves in winter the tree could be identified by the winter buds, where Willows just have one outer scale and the Poplar has several. However as there is much to say about the Willow, I will leave the Poplar for another blog in the future!
Pictures by Matt Summers (MS) and Mike Poulton unless stated. The links provided on the scientific and common plant names provide more detailed information as well as good pictures on each species. Also special thanks to PFAF which provides a wonderful plant database of not just native plants but any useful plants all over the world.
First a bit about the classification of the Willows.
“ Identification is often made difficult by the extensive degree of hybridisation” (68 combinations at present known in B.I., of which 20 are hybrids between 3 species). Only those hybrids considered certainly or very probably correctly identified are listed in Stace.
Hybrids can also be formed due to us planting Willows as an ornamental or for basketry in vicinity of other native Willows.
Catkins and both young and mature leaves (collected in July- September) are desirable for correct identification.
The genus Salix or Willow is separated in 3 sections. As always in classification the species in each section have things in common.
The first Section is SALIX and has 10 species of which 5 can be said to be true natives and 2 are archaeophytes. They are all trees or tall shrubs.
- Salix pentandra or Bay Willow and here brc record
- S. x meyeriana (Salix fragilis x pentandra) or Shiny-leaved Willow
- S. euxina or Crack Willow + nbn atlas This is one of the parents of the Hybrid Crack Willow below.
- S. x fragilis or Hybrid Crack Willow: It is a hybrid between Salix euxina (see above) and Salix alba (see below), and is very variable, with forms linking both parents also see brc.
- S. alba or White Willow (archaeophyte) and brc
- S. triandra or Almond Willow (arch.) and brc
- S. x mollissima (Salix triandra x viminalis) or Sharp-stipuled Willow (arch.) and brc
Section 2 is VETRIX and has shrubs or small trees.
- S. purpurea or Purple Willow and brc record
- S. viminalis or Osier (arch.) and brc
- S. x smithiana (Salix cinerea x viminalis) or Broad-leaved Osier
- S. x calodendron (Salix caprea x cinerea x viminalis ) or Holme Willow
- S. x stipularis (Salix aurita x caprea x viminalis) or Eared Osier
- S. x holosericea (Salix viminalis x cinerea) or Silky-leaved Osier
- S. x fruticosa (Salix aurita x viminalis) or Shrubby Osier
- S. caprea or Goat Willow and PFAF and brc
- S. cinerea or Grey Willow and PFAF and NBN
- S. x laurina (Salix cinerea x phylicifolia) or Laurel-leaved Willow and here
- S. aurita or Eared Willow or here or brc.
- S. myrsinifolia or Dark-leaved Willow
- S. phylicifolia or Tea-leaved Willow
- S. repens or Creeping Willow and PFAF
- S. lapponum or Downy Willow or here
- S. lanata or Woolly Willow and PFAF
- S. arbuscula or Mountain Willow or here
Section 3 is CHAMAETIA, which are all Dwarf shrubs and has only got 3 (native) species.
- S. myrsinites or Whortle Leaved Willow
- S. herbacea or Dwarf Willow and brc.
- S. reticulata or Net Leaved Willow
Much of the below information comes from Wikipedia. But for easy reading I will edit the information into bullet points as far as possible.
Willows, also called Sallows, and Osiers, form the genus Salix which are around 400 species of deciduous trees and shrubs, found primarily on moist soils in cold and temperate regions of the Northern Hemisphere. Most species are known as Willow, but some narrow-leaved shrub species are called Osier, and some broader-leaved species are referred to as Sallow (from Old English sealh, related to the Latin word salix, willow). Some willows (particularly arctic and alpine species) are low-growing or creeping shrubs; for example, the Dwarf Willow (Salix herbacea) rarely exceeds 6 cm (2.4 in) in height, though it spreads widely across the ground.
Several native willows are attractive enough to plant in the garden or for the rockery if it is a Dwarf Willow!
This is a stiffly pendulous small tree with yellowish branches, ovate leaves, and large grey catkins with yellow anthers opening before the leaves. You can watch this Youtube film in order how to prune it after flowering.
Salix babylonica or Weeping Willow is a commonly planted tree in large parks or gardens and especially looking good in early spring near water with its large lime-green foliage nearly touching the water. It is however not native.
There are several other ornamental willows, usually not native species such as :
- The leaves and bark of the Willow tree have been mentioned in ancient texts from Assyria, Sumer and Egypt as a remedy for aches and fever, and in Ancient Greece the physician Hippocrates wrote about its medicinal properties in the fifth century BC!
- Native Americans across the Americas relied on it as a staple of their medical treatments. It provides temporary pain relief.
- Salicinis metabolized into salicylic acid in the human body, and is a precursor of aspirin.
- Willows produce a modest amount of nectar from which bees can make honey, and are especially valued as a source of early pollen for bees.
- Poor people at one time often ate willow catkins that had been cooked to form a mash.
Some of the human race’s earliest manufactured items have been made from Willow.
- A fishing net made from Willow dates back to 8300 BC. Basic crafts, such as baskets, fish traps, wattle fences and wattle and daub house walls, were often woven from Osiers or Withies (rod-like Willow shoots, often grown in coppices).
- One of the forms of Welsh coracle boat traditionally uses Willow in the framework.
- Thin or split Willow rods can be woven into wicker, which also has a long history. The relatively pliable Willow is less likely to split whilst being woven than many other woods, and can be bent around sharp corners in basketry.
- Willow wood is also used in the manufacture of boxes, brooms, cricket bats, cradle boards, chairs and other furniture, dolls, flutes, poles, sweat lodges, toys, tool handles, veneer, wands and whistles.
- In addition, tannin, fibre, paper, rope and string can be produced from the wood.
- Willow is also used in the manufacture of double basses for backs, sides and linings, and in making splines and blocks for bass repair.
- Willows are used as food plants by the larvae of some Lepidoptera species, such as the mourning cloak butterfly. Ants, such as wood ants, are common on Willows inhabited by aphids, coming to collect aphid honeydew, as sometimes do wasps.
- As mentioned earlier, most of the Willows are a good early source of pollen and nectar for bees.
- The thinner stemmed willows are used for weaving baskets
- Willow is used to make charcoal (for drawing)
- Living sculptures are created from live Willow rods planted in the ground and woven into shapes such as domes and tunnels.
- Willow stems are also used to create garden features, such as decorative panels, obelisks and garden constructions such as bowers.
Almost all Willows take root very readily from cuttings or where broken branches lie on the ground. The few exceptions include the Goat Willow (Salix caprea) and Peachleaf Willow (Salix amygdaloides).
One famous example of such growth from cuttings involves the poet Alexander Pope, who begged a twig from a parcel tied with twigs sent from Spain to Lady Suffolk. This twig was planted and thrived and legend has it that all of England’s Weeping Willows are descended from this first one.
Willow is grown for biomass or biofuel, in energy forestry systems, as a consequence of its high energy in/energy out ratio, large carbon mitigation potential and fast growth. Large-scale projects to support Willow as an energy crop are already at commercial scale in Sweden. Programs in other countries are being developed through initiatives such as the Willow Biomass Project in the US, and the Energy Coppice Project in the UK.
- constructed wetlands
- ecological wastewater treatment systems
- land reclamation
- streambank stabilisation (bioengineering)
- slope stabilisation & soil erosion control
- shelter-belt and windbreak
- soil building & soil reclamation
- tree bog compost toilet and
- wildlife habitat.
Willows are often planted on the borders of streams, so their interlacing roots may protect the bank against the action of the water. Frequently the roots are much larger than the stem which grows from them.
Willow is one of the “Four Species” used ritually during the Jewish holiday of Sukkot. In Buddhism, a Willow branch is one of the chief attributes of Kwan Yin, the bodhisattva of compassion. Christian churches in northwestern Europe and Ukraine and Bulgaria often used Willow branches in place of palms in the ceremonies on Palm Sunday.
Pollarding: A pruning system involving the removal of the upper branches of a tree, promotes a dense head of foliage and branches. In ancient Rome, Propertius mentioned pollarding during the 1st century BC. The practice has occurred commonly in Europe since medieval times and takes place today in urban areas worldwide, primarily to maintain trees at a predetermined height.
In my native lowland Holland, willows are often seen neatly pollarded along roads, ditches and rivers. Usually Salix alba is used for this. This is traditional and aesthetical as well as practical when the water table is mostly very high and in combination with strong winds, tall trees would just keel over!
The form Salix alba var. vitellina ‘Britzensis’ can also be seen with its glowing orange red stems in winter.
Traditionally, people pollarded trees for one of two reasons:
- Fodder pollards produced “pollard hay”, which was used as livestock feed; they were pruned at intervals of two to six years so their leafy material would be most abundant.
- Wood pollards were pruned at longer intervals of eight to fifteen years, a pruning cycle that tended to produce upright poles favoured for fence rails and posts, as well as for boat construction.
One positive consequence of pollarding is that pollarded trees tend to live longer than unpollarded specimens because they are maintained in a partially juvenile state and because they do not have the weight and windage of the top part of the tree.
Older pollards often become hollow, so can be difficult to age accurately. However an interesting garden can grow inside those old crowns!
Pollards tend to grow slowly, with narrower growth rings in the years immediately after cutting.
Unusual non native willow in Sutton Park: