Willows are one of the most versatile and useful of woody plants suited to the temperate climate. They range from creeping plants a few inches high, thriving in alpine conditions, to shrubs shielding other plants from salt-laden winds, to trees 25 metres high gracing the riverbanks of fertile lowland valleys and plains.
Not only are willows adaptable to a wide range of conditions, but the uses to which they can be adapted are many and varied.
Traditionally, they are used for making baskets of all sizes and shapes, for protecting crops and stock, and in the reclamation of degraded and polluted land. In recent times their role has expanded enormously with the development of bio-engineering. They are being planted as live willow walls next to motorways, where they shield against sound and pollution; planted to stabilize river banks; and cropped to provide energy to heat buildings and generate electricity.
They are cheap, easy to establish from cuttings, and they respond well to regular cropping, needing no fertiliser input. Indeed, they will build fertility in poor and depleted soil, and are of great value to wildlife.
Willows have been highly valued by man since pre-Christian times and the renaissance of interest in willows now taking place will continue to provide us with many more imaginative uses for this versatile genus Salix.
I trust you will find the following information useful in choosing appropriate species and varieties for your own needs.
There are three main species of willow commonly used in basketry in Britain.
This is by far the most common species grown commercially today, being suited to growing conditions on the Somerset Levels. It produces high quality rods which are hard and pliable and generally 1.5m to 2.2m long. Mainly available, processed into 'Buffs' but can be used with the bark unpeeled. Black Maul is the variety that is usually available, being considered the best all rounder. However, a far wider variety were once grown, when regional differences and individuality were considered more desirable than standardisation.
This produces some of the finest rods of the willow genus. They are tough, hard and pliable. The finer varieties may range from 0.9m to 1.5m long whilst other more vigorous varieties may reach 2m to 3m in some cases. They are suitable for fine superior basketware such as hampers, fruit baskets and craft items. Once widely grown in the Mawdesley area of Lancashire where fine baskets of white (peeled but not boiled) willows were a speciality. Attractive colours ranging from pale shiny green to green/purple mottling to dark purple make it ideal to use unpeeled.
More vigorous and hardy than S. triandra, it will produce rods from 1.8m to over 3m in some varieties. Traditionally used for baskets of the sturdy, practical type such as fishing and agricultural baskets. Mostly used with the bark unpeeled. Two year old material is often used for hurdle uprights, legs and large components of furniture, handles and the like.
Some other useful species are as follows:
Although the species listed above are generally preferred by professional basketmakers, almost any other type can be used to some extent. Those with a creative instinct will find plenty of scope for experimentation.
For tall windbreaks 20m or so the tree willows S. alba and S. fragilis and hybrids are ideal. They will grow quickly and tolerate mechanical trimming. S. fragilis is more spreading, whilst S. alba has a more upright habit. Both are often pollarded and are a classic feature of the lowland British landscape.
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HIGHLY RECOMMENDED For quick, effective shelter, shrubby fast growing willows such as S. viminalis are recommended. Such a windbreak can grow 2m - 3m in the first growing season. It can subsequently be trimmed to the required height or, if allowed, could grow to about 8m. Windspeeds can be reduced by as much as 60% even during the winter. Recommended are:
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For shorter windbreaks or tall hedges S. rubra and the vigorous varieties of S. purpurea are often used. They have proved effective in restricting windblown soil erosion on arable land in the fens.
Other willow varieties, especially when mixed, will also make attactive garden hedges which would include attractive leaves, colourful stems and early catkins.
S. viminalis and S. purpurea are both widely used in Britain and the continent to stabilise vulnerable soil on riverbanks and steep verges. Their suitability is twofold. Firstly they produce a dense fibrous mat of roots, thus binding the soil. Secondly, those varieties with a bowed or spreading habit will inhibit run-off and cause organic matter to build up around stem bases which may then root, creating a thicket effect and therefore trapping yet more detritus.
Bioengineering techniques using faggoting and spiling, etc., are also being increasingly used, particularly on vulnerable riverbanks, with successful results.
Further information is available on request.
There is now a definite trend towards finding biological solutions to (often man made) environmental problems.
In the field of waste management this has led to the development of biological filtration systems. Mini wetland ecosystems are constructed mainly using reeds and willows which break down and purify a variety of effluents such as farm slurry, human sewage and industrial wastes. The effluent that is treated in such systems is not only detoxified but actually converted into valuable plant material. For example sewage is converted into willow which is then made into baskets. Thus by following natural principles a problem is turned into an asset.
Such systems are usually easier and cheaper to implement and manage than high tech solutions which can be not only vastly more expensive but also less effective.
Fast growing varieties are usually preferred as they have a greater capacity to absorb and process the effluent being treated.
Limited trials by the Forestry Commission in Wales have shown that the following are of value as pioneer species on cold, wet sites at high altitudes:
Research has shown the following varieties to be resistant to salt laden winds by the coast:
Land Reclamation and Soil Improvement
The root action and abundant leaf litter of willows make them very effective pioneers in improving the physical structure and nutrient levels in the poorest of soils. Often they are used in the first stage of rehabilitation ultimately improving conditions to allow a wider range of plants to flourish.
Trials in this country have shown that coal spoil with a high pyrite content can be successfully treated with a combination of sewage sludge/cake application and willow planting.
Because of the adaptability of the growing plant and the rapid growth and versatile nature of the willow rods, such sites are thus transformed from a visual eyesore and source of polluted run off water, to a rich habitat, landscape amenity and valuable resource for willow products. For roadside planting where atmospheric pollution is high and also for sites where the ground is heavy and compacted, the following are recommended for the worst sites:
On the better sites S. alba and hybrids are suitable.
Biomass is the total mass of living matter in a given area. Willows cut every 3 years, known as short rotation coppice (SRC), produce more biomass than most other crops in the British climate. Yields can be as high as 20-30 tonnes of fresh material (or 10-15 dry tonnes when seasoned) per hectare per year on some sites.
The rods are cut, dried, chipped and burned to produce heat and/or electricity. On the continent electricity-generating and district heating schemes have been in operation for a number of years. Alternative uses are the mulching of paths and play areas, equestrian purposes, animal bedding or, when composted, soil conditioning. The landscape industry also uses large amounts of woodchips which can fetch as much as �30 per tonne. 1 tonne is roughly equivalent to a pick-up truck load and takes one person about 1 hour to produce using a petrol-driven chipper.
Suggested planting densities are 10,000-20,000 per hectare equivalent to 1 x 1 m to 1 x 0.5 m spacing.
Recommended fast growing varieties known as super-willows are:
Grants are now available from the Forestry Authority (FA) to plant willows as SRC. Set-aside land may also be eligible. Contact your local FA office.
S. alba and S. fragilis and hybrids are both grown for timber, having a high volume of production suitable for pulp, particle board, etc. They will burn well if thoroughly seasoned. For fuel production "Super Willows" managed as SRC and cut every 4 to 5 years will produce logs several inches in diameter suitable for wood or multi-fuel burners.
Willow catkins produce nectar and pollen for bees early in the year when little else is available. Indeed they are often used in orchards to attract pollinating insects as well as providing shelter. The following examples are noted for their early and abundant catkins.
It can be said that all trees have some aesthetic value, however, a number of willows are particularly noted for the following features.
See bee fodder.
Many willows have colourful bark, especially on young stems, which add welcome colour to the Winter landscape. This may be enhanced by cutting hard back in March every few years.
Spreading bush or small tree up to 10m high. Rich moist lowland soils acidic to pH 5.5. Does not like extreme or difficult situations.
Also the following named varieties:
Sweet Willow, Black Maul, Newkind, Grisette, Light Newkind, Grisette Noire, Dark Newkind, Petite Grisette, Whissender, Dark French, Glibskin, Light French, Black Top, Brunette Noire, Stone Rod, Noire de Villaine, Sarda, Spanardia, Pomeriana, Black German, Norfolk, Black Hollander
Variable habit, sometimes spreading, occasionally reaching 5m. Tolerates sands, peats and clays acidic to pH 5.
Also the following named varieties:
Lancashire Dicks, Scharfenbergensis, Leicestershire Dicks, Whipcord, Green Dicks, Goat, Dark Dicks, Uralensis, Dicky Meadows, Procumbens, Brittany Greens, Jagielonka, Abbeys, Lambertiana, Welsh, Japonica, Helix, Angustifolia, French Strain, Links Dutch, Irette, Goldstones, Elagantissima, Reeks, Eugenii, Nicholsonnii Purpurescans
Tall shrub up to 10m. Moist heavy soils, tolerates peat and acidity to pH 4.5.
Also the following named varieties:
Bowles Hybrid, Gallica, SQ683, Jezewski, Gigantea, Longskins, Mullatin, Pulchra Ruberima, Refenweide, Filleretiana, Irish Rod, Stone Osier, English Rod, Longifolia, Yellow Osier, French Osier, Readers Red, Tenuifolia, Black Satin, Brown Merrin, Winsendra, Brown Mirriam, Northern Ireland Dark Bark, Northern Ireland Light Bark.
Large shrub or small tree usually 6-8m high, occasionally 12m. Tolerates dry sands, poor soils and acidity down to pH 4.5.
Also the following named varieties:
Continental Purple, E, Oxford Violet, Aglaia, Black Willow, Praecox, Sinker, Latifolia, Salix alba - White Willow,
Tree willows up to 25m. Generally moist, fertile soils, often near running water. Tolerates acidity to ph5. S. alba has a more uniform habit and is more tolerant of drought and coastal conditions.
Also the following named varieties:
S. alba, Oirschot Boxtel, Thegelen, Siren, Vitellina, Vitellina Nova, Caerulea, Vries, Drakenburg, Liempde, Malontelelo, Sericea, Chermesina Britzensis, Chermesina Cardinalis, Chermesina Yelverton, S. fragilis, S. alba x fragilis, Flanders Red, Redskin, Natural Red, Fransgeel Rood, Golden Willow, Regalis, Hutchinsons Yellow.
Other varieties not listed are also available.
For best results the site may be dug and enriched with organic matter and/or fertilizer. However, willows are very adaptable to a wide range of soil conditions and on my own nursery they establish and grow well without digging or fertilizing. The single most important factor in a new bed or plantation is good weed control during the first two growing seasons. Several techniques may be employed. On a large or medium scale, cultivations with tractor-mounted equipment, rotovator or wheeled hoe are appropriate. However, on a small scale, a simple and effective method is to use black polythene as a weed-suppressing mulch. Spacings may vary from 60cm x 30cm (i.e. 60cm between rows and 30cm between plants) to 1m x 50cm. A spacing of 1m x 50cm is equivalent to 20,000 plants per hectare. Use the closer spacings for annual cropping of less vigorous varieties and the wider spacings for more vigorous varieties or where cropping is every 2 or 3 years. When deciding on spacing take into account weeding and cropping methods. For example if weeding with a rotovator make sure the rows are wide enough to rotovate between.
My own preferred standard spacing is 90cm x 60cm. For closely spaced hedges and windbreaks, plant the cuttings 30-45cm apart in single or double rows.
At the closer spacings 50 cuttings could be planted in a bed as small as 4m x 3.6m while 100 cuttings would need one about 4m x 7.1m.
The cuttings are best planted in situ, putting most of the cutting in the ground with 2 or more buds above the surface. When using black polythene mulch it is important to make the holes small enough to prevent weeds from emerging around the base of the cutting. First year growth will be rapid, typically 1m to 3m. They can then be cut back to produce more bushy growth in the second season and subsequently cropped each year if desired.