Invasive Rhododendron in Woodlands – a Permaculture Approach

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Introduced to Britain by the Victorians, Rhododendron has become a very popular garden plant. Unfortunately however, one particular strain, rhododendron ponticum, has become invasive in British woodlands.

The plant tends to crowd out all other species, diminishing biodiversity and destroying the ecosystems which normally thrive in woodlands. They prevent light from reaching the woodland floor and can grow as tall as trees, the weight of their entangled branches even pulling trees down.

Many different approaches to controlling rhododendron have been tried throughout the UK. One approach is herbicide, in particular glyphosate weedkiller, which is injected into the rhododendron stems after drilling or sprayed onto young foliage. This approach is extremely expensive and leaves glyphosate residues in the soil. It also leaves a forest of dead rhododendron plants which in itself doesn’t necessarily result in the restoration of woodland ecosystems.

There is the ‘lever and mulch’ method, which aims to kill rhododendron without the use of herbicide. This method can be effective but is very labour-intensive and again does not let light in to the woodland floor for ecosystems to regenerate. Using machinery to shred and crush rhododendron has a similar result, and is very energy-intensive.

Valley Wood has just such an invasive rhododendron problem. But the more time I spend there, and the more I work with the landscape and the existing ecosystem, the less satisfied I have become with these traditional approaches to rhododendron control. I started wondering what a Permaculture approach to the rhododendron problem might look like.

The basic premise of traditional control methods is that rhododendron is an invasive alien and must be killed, uprooted, cleared completely from the site and surrounding areas in order to allow the indigenous woodland ecosystem to regenerate. Although some of the neighbouring woodland plots have had this treatment, the rhododendron has come back again, and it very soon became obvious to me that this kind of approach just could not work at Valley Wood.

So I started to do some research to learn more about rhododendron. Since it was so plentiful and tenacious, I wondered if a Permaculture approach would allow me to turn a problem into a benefit and begin to view it as a crop of some kind.

Rhododendron was originally introduced into some woodlands because it is a very dense, evergreen shrub, which meant that it provided excellent cover for game birds. Now, this property of course has not gone away, so I immediately realised that one good thing about my woodland is that there is ample cover for birds all year round. Many insects can be found on the rhododendron too – every time I work at clearing some of it, there is always a Robin following me around picking insects off the cut stems. It’s actually quite enjoyable to have some company while I work – I feel like the Robin is working with me, and getting his dinner at the same time. Some of the rhododendron plants are so huge and dense that it can feel quite magical walking around underneath them, like being in some kind of weird twisted fairytale forest.

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So, the birds like it. And as it happens, so do the bees! Around May to June, when the rhododendron is in flower, there is an amazing display of huge purple flowers which provide large quantities of food for bees and other pollinating insects. This isn’t necessarily good for humans – honey made from bees which have been feeding on rhododendron flowers is actually poisonous and can make you quite ill! But for a couple of months at least, bees will be glad of the display. With the changing climate, I have even seen some rhododendron plants flowering in the autum, winter and spring.

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Another property of rhododendron is that it makes excellent firewood – even when it is green. It is a fast-growing hardwood with a very high calorific content, and the stems of larger plants are so thick that they can easily be sawn up into logs which are perfect for either an open fire or a wood burning stove. I have taken rhododendron logs home to burn in my woodburner during the winter, but a particularly good use for the rhododendron firewood is on-site, where I need to keep warm during the winter when I am there working. Burning rhododendron means that I can generate firewood as I am clearing the rhododendron from the woodland, meaning that I don’t have to have a big stack of it seasoning and I don’t have to cut down broadleafed trees and season them for use as firewood on-site, I can leave them standing and growing. So rhododendron has become my staple firewood, leaving the trees for better purposes.

Here are some rhododendron stems ready to be cut into lengths for firewood:-

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The smaller twigs and branches I tie into bundles with string, and one bundle makes a perfect firelighter. The dry twigs catch light incredibly easily, and the rush of heat is plenty to get bigger logs and branches burning. So butchering and using the different parts of the plant gives me everything I need to keep warm when I am working at the woodland. One of the principles of Permaculture is that everything has its place in the system – and the system at Valley Wood includes me, the woodland manager, and rhododendron to provide firewood to keep me warm. The rhododendron has gone from being an alien species which requires total eradication (impossible and a huge ongoing effort) to being a fast-growing hardwood wood fuel which keeps me warm even as I clear it to let light through to the woodland floor. A Permaculture approach where nothing is wasted, and everything has a function.

Even having found a place for rhododendron in the Valley Wood Permaculture system, there is far too much of it, and large areas need to be cleared to allow the woodland to regenerate. Once I’ve started cutting into an area of rhododendron, what is left looks very barren and bleak, as can be seen from these photos:-

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In the photo above, you can see the normal woodland floor ecosystem in the foreground which has regenerated after rhododendron clearance – lush with moss, ferns, foxgloves and all manner of other plants and fungi. The newly cleared area in the background is barren, although there are seeds lying dormant in the ground. I sometimes assist the regeneration by sowing a mix of woodland flower seeds onto cleared areas.

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In the area above, one effect of the huge rhododendron plants was that there were many trees which had grown very tall and spindly instead of bushing out, as they grew towards the light competing with the rhododendron. When I cut the rhododendron down, the weight of the branches pulled down many of these trees. But I found that what I had ended up with was a lovely collection of long, straight poles, perfect for shelter building! So I cut the fallen trees off at the base and used them. With sunlight now coming through to the woodland floor, the cut stumps will start to grow again, giving an area of hardwood coppice. In the photo above, you can see some of the tall, pole-like trees still standing in the background.

Whilst cutting rhododendron stems for firewood, occasionally I would come across one which was nice and straight, or curved in quite an interesting way. I started to wonder whether they would make good walking sticks. A few years back I bought a set of whittling knives, so I thought I would have a go at making a few rhododendron staffs.

I found the wood very pleasant to work with, the bark has an almost reddish tinge and the wood underneath it is lovely and white. There is a lot of quartz in the rock at Valley Wood, so I easily found small quartz crystals with which to adorn the new staffs. I found that I really enjoy making them. Apparently rhododendron wood has the property of protecting the staff owner from enemies! I have already sold one of these staffs and hope to sell more as my staff-making improves. And rhododendron wood seems to be an excellent, strong wood for walking sticks!

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One of the ways which rhododendron spreads is when heavy branches bend down and touch the soil, and the branch puts out new roots at the point of contact. Like other hardwoods, rhododendron can be propagated from cuttings, but rhododendron is particularly easy to get to root.

There are a few places in the woodland where I have wanted some kind of screen to obscure the view of the campsite and shelter, or the forest garden. I did wonder about buying a couple of hundred hawthorn whips and planting them to make hedges. This seemed like quite a laborious and expensive option, the hedge would not really be tall enough for a couple of years at least and in the winter it would not serve as a screen as all of the leaves would fall.

Whilst cutting rhododendron, I noticed that after I had separated out the main stems for firewood, I was left with a big pile of branches of three or four nodes, which were very bushy and green – perfect hedging material, in fact. So I decided to take advantage of rhododendron’s easy rooting property, and simply took all of the cut branches and pushed the ends into the ground along the track above the campsite, forming a very dense, very instant and completely free-of-charge hedge!

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Again, using the discarded parts of the harvested rhododendron plant in this way means that nothing is wasted and everything has a use – Permaculture in action.

There are even more uses for rhododendron – the leafy stems can be harvested and sold to companies providing foliage for florists. There are a couple of reports which make very interesting reading regarding generating an income from rhododendron:- Profit from Rhododendron and Rhododendron Foliage Harvesting.

My aim with Valley Wood is to eventually clear most of the rhododendron from the woodland, allowing the woodland ecosystem to regenerate. But in the process I will benefit from firewood logs, kindling, poles for building, free hedging and the rhododendron plants I leave in place will provide cover for birds and screens. I think that the Permaculture approach to rhododendron control says that although the plant has come to Britain as an invasive alien species, it is here to stay and must find its place in a balanced system. Left to its own devices in the wild, it will upset the ecosystem balance, but as part of a managed Permaculture system with humans included, it has a place as a productive plant which is kept under control by regular harvesting for its products, with no need for the damaging use of herbicides or energy-intensive industrial clearing efforts.

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Basket Case

Inspired by a design I saw at a friend’s party last November, I decided to make myself a fire basket from an old washing machine drum and a wheel rim. And here it is!

Making A Rocket Stove

There are loads of good videos on YouTube about how to make your own rocket stove, but this is how I made mine.

I used two catering sized vegetable oil tins and a normal baked bean size tin.

First using a strong pair of scissors I cut the top off the first large tin. Better to use tin snips if you have them but good scissors will do. Start the cut by making a hole in the can with a hammer and a sharp screwdriver.

Then I cut both ends off the second large tin and rolled it up to make a narrow tube. I used garden wire to hold it tight.

Then I took both ends off the small tin using a can opener, and using the screwdriver scratched a circle near the bottom of both the big tin and the narrow tube. The circle is nearer the bottom of the tube than the tin because the tube sits inside the big tin to form the flue.

I cut a circular hole in the big tin and the flue, and put the small tin through both. Then I filled in the outside of the flue with wood ash from my wood stove, to insulate it.

Finally I cut a hole on the middle of the bottom of the second large tin which was left over, and made a lid for the stove. I cut some 1cm notches in the top of the stove so the lid would push down into it a bit, and then hammered down the edges to keep the lid in place.

Finally I sprayed the stove black with woodstove paint. Voila!













Log In

We received our first delivery of seasoned logs for the wood stove since February yesterday. We have survived since then on solar power for hot water and some scrounged logs for the odd fire.

These logs are lovely though, cut to just the right size and dried so they burn beautifully!

Stone Free

Had a great day yesterday at Transition Stone’s “Festival of Possibilities” – the location was the very beautiful Hayes at Stone, a big old house in acres of picturesque grounds which is home to a small community of Transitioners giving a whole range of workshops, everything from bread-making, bicycle maintenance and diesel engine vegetable oil conversions to micro-hydro and woodworking using a home made pole lathe. I gave my Green Cottage presentation as a contribution.

I don’t know if it was a combination of the venue, lovely weather and kindred spirits or the home made cake, soup and crusty rolls, but the whole day was really heartwarming and gave me a real lift. It’s not that often I find people who are really on my wavelength but this was one occasion. Thankyou Transition Stone for a great day and a big success, all power to you!!

Love the home made geodome 😉

Feeling Chipper

Bought a garden shredder/chipper today for £80 – after much debate with myself I decided to get one to deal with the huge quantities of ‘green waste’ my little garden generates.

We don’t have bins for green waste round our way as the council don’t think we have gardens to speak of, being a terraced housing estate. But every year, especially in the autumn, I end up burning huge quantities of vegetable matter because I simply don’t have any other way of getting rid of it.

I didn’t really want to get a shredder as it uses power of course, and it’s just another thing to take up space in the house. But being able to recycle all my green waste into a useful mulch is really going to benefit my garden, I think.

At the moment the weather is so dry that a mulch of shredded twigs and leaves will hopefully help to keep the moisture in the soil. And one thing the soil in my garden is really short of is nice thick organic matter – over time as the mulch decomposes and is incorporated into the soil by worms, it should really improve the soil quality – a perfect in-house solution really. So I decided that the chipper was a good idea – it won’t be used that often really, but when it is, it will be invaluable.

Fun in the Sun

We are having a bit of a community fun day today in our local park, with all sorts of stuff including home made food, herb planting, face painting, information stalls about recycling and all sorts of other stuff.

The weather is amazing. April is the new June!!

Wood Fuel: What If . . . ?

I sometimes get asked – and it is a fair question – ‘what would happen if everyone did what you are doing?’. One of my main aims with the Green Cottage eco-renovation project is to find solutions which are replicable at different levels. Solutions which can only ever apply to a few people in special situations are not really going to help us achieve the kind of transformation we need to, although of course everyone’s situation will be special to a degree.

When it comes to the use of wood as a fuel, the issue is quite complex and there are quite a few different factors at play.

At the time of writing, there is a reasonably plentiful supply of wood fuel available. This comes mainly in the form of seasoned logs which are sold typically by farmers and tree surgeons sourced from waste wood from their own arboricultural operations. Most local authorities’ parks and countryside services produce large quantities of waste wood annually, a lot of which is still chipped and used as a mulch or covering for paths etc. Some is even taken to landfill.

So at present there is some slack which remains to be taken up in the wood fuel market.

However, the wood fuel supply is likely to begin to come under pressure in the not-too-distant future. Not only are more and more people buying wood stoves – for ecological reasons, for warmth security reasons (they work during a power cut) or for financial reasons (the rising price of fossil fuels) – but across the country, planning permission is currently being given for dozens of biomass power stations and smaller Combined Heat and Power plants. These plants burn a LOT of wood, so much in fact that many of these new power plants are planning to import their biomass feedstock from abroad.

All this means that at some stage, log fuel may well become either a lot more expensive, or unavailable at any cost. This would be a real shame, and this is where the principled ‘green socialist’ for want of a better phrase comes out. I am normally fairly apolitical when it comes to these things, but a number of principles are at stake here:-

– log fuel is by its nature a low-energy, low-carbon renewable fuel. It takes very little energy to prepare (chopping and stacking for seasoning) and most of its energy footprint is in the harvesting of the logs and the distribution of the log fuel. Other forms of biomass fuel such as wood pellets and wood chip have a much higher embodied energy, because they need to have a quality grade for use with high technology furnaces.

– log fuel is typically produced and distributed locally, whereas higher grade biomass fuel typically is not.

– log fuel is ideal for tackling fuel poverty, a condition which is commonly found in 100 year old solid walled terraced brick town houses. This type of property has a chimney, a good thermal mass, is typically insulated by two more properties on either side, and in short is perfect for the installation of a modern, clean-burning, high efficiency wood stove room heater, if not a stove which also heats the hot water and runs the radiators. Experience has shown that even a simple room heater can cut gas heating bills by two thirds.

– wood ash is a perfect fertiliser for growing fruit in an urban setting, as it contains potash which is the main ingredient in any ‘fruit fertiliser’ which you can buy.

Other types of house such as detached and semi-detached may be more suitable for other types of alternative heating such as heat pumps, which are more expensive than wood stoves and so more appropriately suited to the socio-economic status of such householders . New houses should of course be built to require little or no heating.

I do fear that there is a danger that locally produced wood resources may be diverted to feed large biomass power stations, which in my humble opinion would be a Bad Thing. There is certainly a place for fast-growing energy crops such as willow, poplar or even miscanthus grass to feed biomass plants, but local log fuel should have its own supply chain and used to heat local, relatively fuel poor homes.

A rise in the price of log fuel would not be all bad, however: at present most local authorities have areas of woodland which are currently unmanaged due to lack of funding fir proper woodland management programmes. Proper management can not only result in a woodland becoming productive in terms of wood fuel and other wood products, but thinning and other management techniques are also better in terms of biodiversity opportunities. A higher price (and therefore value) for wood fuel and other wood products could provide the necessary funding streams to enable proper business plans to be formulated for the sustainable management of currently marginal woodlands.

Besides, I never want to have to resort to burning coal, that would most definitely be a retrograde step 😉

Constant Planks

Because we have a wood stove, people tend to donate bits of wood they want to get rid of for us to burn.

But quite often we will be given bits of really nice wood that it seems a real shame to just cut up and burn.

Here’s our current stack of quality timber – a pack of six posts I found just lying on a pavement one evening, apparently unwanted; a large beam given to me by a builder who often does jobs for me; and all the slats from a futon which was given to us by a friend.

No idea what to do with them yet, but I’m sure I can use them for something! The green box on the right is a lean-to greenhouse kit I’ve bought for the back of the house – some of the timber could be used to make a kind of cold frame to go next to it, together with some spare corrugated plastic I have left over from my last effort at a cold frame, which turned out to be in the wrong place and didn’t get much sun.

Hopefully I will be able to get out in the garden this weekend if the weather permits, and get it cleared up a bit for the coming growing season, and so I can get these greenhouses (greenhice?) up.