Gorse and Broom: Crops with a future?
A number of years back I came across a book edited by environmental entrepreneur Paul Hawken called “Drawdown” with the lofty and hyberbolic subtitle “The most comprehensive plan ever proposed to reverse global warming”. The book compiles profiles of roughly 100 of the most promising solutions available to help tackle climate change. The solutions analysed and presented include wide ranging energy technologies; innovations to do with buildings and cities; family planning and education; new or improved forms of transportation and material sciences; and a wide scope of land use and food ideas.
In the “coming attractions” section, which listed exciting ideas which show great promise but need more research, a profile of “intensive silvopasture” particularly caught my eye. The profile read -
“Silvopasture is a common form of agroforestry, practiced today on over 350 million acres worldwide. The theory is simple: Combine trees or woody shrubs and pasture grasses to foster greater yields. Cattle fatten faster and provide better-tasting meat than in any other system. Rarely are livestock and climate mitigation used in the same sentence; silvopasture, however, sequesters up to three times more carbon per acre than grazing alone — ranging from one to four tons per acre in the tropics and averaging 2.4 tons in temperate regions. What happens if you intensify the silvopasture process? Add more cattle, plant different types of trees, and rotate the herd more quickly? It seems counterintuitive that it could have a beneficial effect on land and climate, as well as human health, but it does… Most intensive silvopasture systems revolve around a quickly growing, edible, leguminous woody shrub. Leucaena leucocephala, planted four thousand per acre, is intercropped with grasses and native trees. These intensive systems require rapid rotational-grazing regimes. They employ electric fences that allow for one- to two-day paddock visits, with forty-day rest periods between. Trees keep the wind in check and improve water retention, which causes increases in biomass. The combination of flora can reduce ambient temperatures in the tropics by fourteen to twenty-three degrees Fahrenheit, which enhances both humidity and plant growth. Species biodiversity doubles in intensive silvopasture systems. Stocking rates nearly triple. Meat production in pounds per acre per year is four to ten times higher than in conventional systems. The tannin content in Leucaena leucocephala seems to protect protein degradation in the rumen of cattle, reducing methane emissions, which partially explains the significant weight gain of animals raised via intensive silvopasture… The key to intensive silvopasture is a fast-growing, high-protein woody plant that can handle heavy browsing and re-sprout quickly. In tropical Australia and Latin America, Leucaena is one that has passed the test so far. Today, intensive silvopasture is practiced on more than five hundred thousand acres in Australia, Colombia, and Mexico… It may sound too good to be true, but there is one more piece of data: In a five-year study of intensive silvopasture in which trees were incorporated with grasses and Leucaena leucocephala, the rate of carbon sequestration exceeded an extraordinary ten tons per acre.”
The claims about the potential for this type of system are quite astounding. A system which can increase productivity to this extent whilst at the same time sequestering the stated volumes of carbon is certainly enough to get you thinking. Leucaena Leucocephala is evidently an extraordinary plant but as it’s a plant native to the tropics it’s unlikely to be suitable for temperate climates such as the British Isles.
In her paper “Intensive silvopasture systems for temperate regions”, Susanne Hale analysed the Leucaena Leucocephala system in Columbia and then asks what are the take aways for replicating something similar in temperate regions? She writes that “probably the most critical element of the temperate analog system is a browse species that can thrive in temperate regions and take the place of Leucaena, which is not frost tolerant.” This would mean finding species with characteristics including being vigorous, browse-tolerant nitrogen fixers; being easily and affordably propagated, ideally by seed; and being palatable and nutritious to browse.
She then provides a list of what she deems the most promising candidates including white mulberry, elm, ash, oak, willow and poplar but singles out black locust as the most promising species which meets all the above characteristics. “A native of the U.S. Appalachian region, it has been somewhat ignored and unappreciated at home, but has been enthusiastically planted, bred, researched (and occasionally cursed) wordwide..”
This thorny plant is an early succession, pioneer species and considered a nuisance and invasive even in the areas it’s native to, yet despite being overlooked or indeed cursed as a pest may have an important role. Yet this is a plant that is native to the Eastern US. Whilst it may be a perfect fit for temperate USA does it make sense to introduce this potentially invasive species to the British Isles? Might we have anything similar that’s native to here?
“The best variety is the one growing by the side of the road,” says rancher Jaime Elizondo who’s leucaena system in Florida has enabled his cattle operation to double its stocking rates.
In the part of the world I am, Easter Ross in the Scottish Highlands, almost everywhere you go the roadsides are dominated by two species: Gorse and broom.
Looking to try to find out more the first thing I found from a google was Marc Bonfils paper “Fodder Trees in Temperate Climate.” Bonfils has been a big influence on my agricultural ideas and over the years I’ve spent untold hours trying to work out how best to implement his novel wheat growing techniques. However I’ve always taken his claims with a large pinch of salt. So whilst my jaw was on the floor when reading what he had to say about the potential of gorse, I had lingering doubts about its validity:
“This non-meteorising leguminous plant produces a green fodder of high nutritional value which livestock prefer even to hay. It gives peak fodder production from the end of November to the end of February arriving just in time to replace exhausted autum pastures. Since time immemorial in Brittany & Wales, livestock (sheep, goats, cattle & horses) fed on ground gorse sprouts during the entire winter period; Cut right to the ground but harvested only once every 2 years, the top of the plant was used for fodder & the rest as animal beding or fire wood. The potent yield of marine gorse would be enormous if we could cultivate it intensively. It would pulverise all European fodder records with an average yield of 50 to 100 tonnes of Dry Matter material /Ha. /year. Because it’s maximum yield is in the middle of winter, just when the pastures have nothing to give, gorse culture could constitute an important link in the fodder chain.”
Surely not?
Wanting to track down a more reliable sources I reached for “Stephen’s Book of the Farm”, the Victorian farming bible. There’s a decent amount in there -
“Like many other useful and beautiful plants indigenous to this country, furze — in some parts called whins, in others gorse — is not so highly esteemed as it ought to be, perhaps on account of its being so common, and of its tendency to grow where it has not been sown and is not wanted. Nevertheless, as food for cattle, sheep, and horses, it possesses very considerable value, and for this purpose it may be grown in any part of the country with success, financially and otherwise.
Furze as Winter Food — The chief value of furze is as a green food for the winter months. It should be cut at least once a year, so that the plants may not be allowed to become too woody and hard. When sown thickly on fairly good land the shoots come up fine and juicy, growing to a length of from 2 to 2 ½ feet. The crop may be cut with a scythe, or with a strong mower past its best for regular harvest work — generally with a scythe.Preparing furze as Food — before being given to stock the furze should be cut into short pieces by a strong chaff cutter, or, better still, bruised and cut by a machine which has been specially designed for the purpose, aptly named the “masticator” and made by Mackenzie and sons, cork. This useful machine may be driven by horse, water or steam power.
Some think it desirable to chop or masticate the furze daily as required; but others perform this work twice a week, and find that the chop keeps well enough.
How fed to stock — an agriculturalist who had thirty years’ experience of furze as food for stock, said: “Cut up the furze with hay for milking cows, and you will make first-quality butter, but pale — with hay for horses, but do not feed too heavily; add 3 or 4 lbs. mangels to counteract a resin the furze contains. Young stock thrive amazingly upon it. Furze-fed cattle are hard to be fattened on other food; oaten straw, with cut furze for them.
Mr R. O. Pringle stated that horses may be kept through the winter on furze without hay, and only a moderate allowance of oats; and the furze gives the horses a fine coat of hair. An acre of well-grown young furze, which is regularly cut, will keep for or 5 horses or cows during the winter and early spring months with very little assistance in the shape of hay or roots. For hard-working horses it should be accompanied by a liberal allowance if bruised oats or other concentrated food. Both horses and cattle take to it readily, but sheep do not eat it willingly except when there is snow on the ground. When grown as food for sheep, the crop is not cut, and in a snowstorm a few acres of young juicy furze are most valuable for sheep.
Composition of Furze — That furze should, in practice, prove to be a useful food, will not surprise any one when it is considered that it contains about 3.20 per cent of albumionoids and about 9.40 of sugar, digestible fibre etc. Its proportion of water is about 72 per cent and fibre 13.33 per cent.”
Looking further into other books from this era, confirmed that not only was it common for agricultural improvers to utilise gorse and broom, but they would actively cultivate both species. Folks would import large quantities of seeds to plant them. Indeed a trip to the Inverness Archive center in Inverness to look at the estate records for a local estate (Novar) in the early period of “Improvements” in the 1790s shows that the estate was importing large quantities of gorse seed.
Further papers show that Gorse in particular is a much treasured and valued plant in Brittany where it is has an array of uses -
Fodder — Because gorse is very high in proteins and nitrogen and is evergreen, it was an especially valuable fodder plant during the winter. It even improved the condition of horses (e.g. Desrez, 1842; Adrian, 1904) and the quantity and quality of milk from sheep and cows (e.g. Calvel, 1809). In France, the use of gorse as fodder was first recommended by a Breton agronomist in 1666 for horse breeding (Desrez, 1842), which was of prime economic importance before mechanization. Over the following centuries, many French publications extolled the qualities of gorse and described the techniques used to cultivate it (e.g. Calvel, 1809; Heuzé, 1856; Adrian, 1904). In its simplest form, gorse was grazed directly by animals in heathlands, but this was only suitable for goats and sheep. For horses and cattle, it was used as fodder in the stable or barn, and it either had to be harvested from the heathlands or hedges, or cultivated in real gorse fields (Calvel, 1809; Adrian, 1904). It was a key fodder crop hich played a very considerable role in the rural economy in Brittany and other poor agricultural regions (Lucas, 1960; Sigout, 1999).
Fertility — The use of gorse as animal bedding and fertilizer has been described since the 18th century (Tessier et al., 1787; Calvel, 1809). Gorse was used to fertilize soil in different forms: as green fertilizer, inorganic fertilizer, or manure. On cultivated land, it could be grown between two rotations to enrich the soil with nitrogen (Antoine, 1999). After clearing a gorse field or heathland, gorse could be burned and its ashes made a good fertilizer. Through the cultivation of gorse fields, and their eventual burning, it was possible to reuse infertile soil to grow more interesting crops (Tessier et al., 1787), such as cereals. Branches of gorse were used as the first layer of cattle bedding: it gave structure to the bedding and enriched it, and made it possible to save straw. Mixed with animal urine and faeces, it became a nutrient-rich manure used to fertilize fields.
Fuel — As it burns fast and produces a lot of heat, gorse was a valuable source of fuel, especially in regions where wood was scarce, such as the windswept coasts of small islands. Gorse branches were harvested from hedges or heathland and incorporated into faggots made from various thorny plants (Darrot, 2005) for use as fuel in homes, bakers oens, lime kilns, or plaster kilns (e.g. Despommiers, 1770; Giraudon, 2007). Sometimes gorse was specifically sown for this purpose (Duhamel du Monceau, 1761).
Fencing — Because of its thorns, dense nature, and rapid growth, gorse forms impenetrable hedges. Planted on banks surrounding farmlands, it was used to fence in cattle, protect livestock and crops from the wind, and to keep intruders (human or animal) out (Calvel, 1809; He, 1856). Gorse as considered b some as the ultimate fence (Biio, 1841). However, it seems that the use of gorse as quickset hedges was less widespread than its other uses in Brittany. When mentioned, hedging was not as well described as its use as fodder (e.g. Tessier et al., 1787) and it was often criticized because gorse hedges frequently invaded neighbouring lands or tended to thin out at the bottom (e.g. Amoreux, 1787; Calvel, 1809; Bixio, 1841). The frequent reference to the ubiquity and size of gorse hedges in England implies a contrasting situation to that in France (e.g. Tessier et al., 1787; Calvel, 1809).
This attribute of being able to become protective fencing has great potential. Thorny shrubs and scrubm which act as nature’s barbed wire have always played the role of nurse plant for slower growing canopy trees that benefit from the protection of these pioneer species. As the old New Forest saying goes, “The thorn is the mother of the oak.” There may well be great potential today in using these species as nurse crops to establish these more conventionally desirable trees, without the associated costs of wire fencing.
Things fall out of practice for various reasons, but often just the fact that they are no longer practiced is not a good reason to reevaluate their potential in today’s context. I’m pretty convinced that both Gorse and Broom have potential to be seen as important agricultural plants once more rather than simply invasive weeds. That these plants have the ability to fix nitrogen, are high in protein (according to Aberdeen University’s Professor Wendy Russell, Gorse contains 17% protein whilst Broom has 21%. The main problem with the cultivation of gorse was likely to have been the labour involved. Processing gorse would have been painful, thankless, and dangerous work. However, should this be revived then it’s unlikely that we’d need to return to this. Forestry mulching/ masticators are regularly used in forestry industries. It’s east to imagine that systems could be designed so that the labour intensive processes of making them palatable could be made more efficient and more acceptable in the context of today.
In looking into this, there have been many attributes that various people have praised these humble plants for in the past. However there appears to be very little contemporary research into either of them in how they could be utilised today. Whilst some of the claims made in the past may be overblown and seen as unscientific, I think there is enough to go on here to start to get excited once again about the potential role these roadside weeds may be able to have in the agricultural systems of tomorrow.
