Sunday 26 August 2018

The potential of willow

A living chair we made. 

This appeared in the Kildare Nationalist, last week. 

Every few years the owner of the land next to us clears away the brush, giving us a front-row seat to what biologists call succession. Bare ground is quickly covered with an army of sprouting weeds, the first being the fastest to grow, seed and die, and each new entry grows more slowly and lasts longer. A year or so into the succession the first trees appear, and pioneer trees in Ireland are willows.

Because they are the tree closest to a weed in behaviour, willows – also called sallies, silver-sticks or osiers -- make an amazing resource everywhere they occur, but such thirsty plants do especially well in our wet climate. They can survive an amazing range of conditions, grow so quickly that a new crop of branches up to two to three metres long can be harvested each year – and few trees have as many uses.

The bark of the white willow (Salix alba) can be boiled to form acetecylic acid, or aspirin. Their fast growth makes an excellent windbreak, and makes them particularly useful for pulling carbon from the atmosphere, repairing some of the damage of climate change. Their wood has multiple uses, and can clean up toxic waste. 

Basket-weavers preferred willow over all other plants – the word for willows, “vikker” in Old Norse, became our word “wicker." Its shoots are highly pliable when wet, lightweight and tough when dry, and grows so quickly that shoots two or three metres long can be harvested every year. Willow groves here were coppiced (cut at the base) or pollarded (cut higher up) from stumps that grew wider every year, growing new foliage and branches that kept the tree alive. The shoots --"withies" they were called in Ireland -- were harvested each spring around St. Bridget's Day, Feb 2, before the spring, from giant stumps that had never been full trees. 

Their roots spread rapidly under the surface of the soil, making them an ideal crop to halt erosion – an important issue in Ireland, where the dramatic felling of the island’s forests over two hundred years washed away much of the soil. Widespread planting of willows back then might have halted some of the erosion that so devastated areas like the Burren.

In addition, the most common willow variety in Ireland, Salix viminalis or “basket willow,” has been shown to be a hyper-accumulator of heavy metals. Many plants help “clean” the soil by soaking up disproportionate levels of normally toxic materials, either as a quirk of their metabolism or as a way of protecting themselves against predators by making themselves poisonous. Many plants soak up only a single toxin, others only a few; Viminalis, it turned out, soaked up a broad range, including lead, cadmium, mercury, chromium, zinc, fossil-fuel hydrocarbons, uranium, selenium, potassium ferro-cyanide and silver.

Willow can also be used for more mundane forms of waste: researcher Alastair McCracken of the Agri-Food and Biosciences Institute of Northern Ireland is conducting trials to see how willow can help clean up effluents like sewage sludge and farm manure.

Perhaps most importantly for us in Ireland, however, willow wood makes an excellent fuel, and since the trees can quickly be regrown, the fuel can be 100 per cent sustainable and zero-carbon. Basket weavers in Ireland harvested ten tonnes per acre per year here in wet Ireland, and in the dry Midwest 19th-century farmers still got nine tonnes per acre. If the wood is for fuel, though, McCracken recommends a three-year rotation, however, for the maximum yield.

Ireland stands out among European nations: no other country has more potential for biomass production, and no other uses it less. Ireland has the highest potential annual yield of wood in Europe according to the SEI. Yet Sweden, Germany, Finland, Austria, the UK and even dry Spain manufacture more than ten times the amount of biomass as we do in numbers, and while some of those countries have more area than we do, many also have more population; Britain is many times more crowded than Ireland, yet devotes more of its land to growing energy. Finland gets 18 per cent of its energy from biomass, according to a study by Sustainable Energy Ireland, in contrast with our 1.3 per cent.

In short, one of our commonest and most easily overlooked trees could be the key to solving many of our problems at once. 

A few baskets I made.
Sustainable Energy Ireland, fact sheet: “What is Biomass?”
“Growing Willow for Energy,” by Alastair McCracken, Local Planet, 30 October 2006.
Phytoremediation. By McCutcheon & Schnoor. 2003, New Jersey, John Wiley & Sons, page 19.
“Enhancing Phytoextraction: The Effect of Chemical Soil Manipulation on Mobility, Plant Accumulation, and Leaching of Heavy Metals,” by Ulrich Schmidt. Journal of Environmental Quality 32:1939-1954 (2003).
“The potential for phytoremediation of iron cyanide complex by Willows,” by X.Z. Yu, P.H. Zhou and Y.M. Yang. Ecotoxicology 2006.

Monday 6 August 2018

Building with straw bales

Straw-bale building under construction. Courtesy of Wikicommons. 

This article appeared in the Kildare Nationalist newspaper. 

These days, the old straw bales that a human could lift have been replaced by mammoth cylinders that require farm equipment. If you can find some of the old rectangular, metre-long bales, however, they can be put to many uses.

On the Great Plains of North America, people stacked them inside a frame to create walls, which were then covered in mud plaster. This technique, pioneered by 19th-century settlers to the Great Plains, is seeing a comeback as people discover the value of energy-efficient buildings. 

Straw is plentiful, does not require the clearing of forests, can form load-bearing walls or can simply insulate. It is easy to work with, and can be stacked and plastered by amateurs. Gathering and baling it does no damage to the environment, and the building waste can be composted. 

It is also one of the most perfect insulating materials around. Insulation is measured in “R-values,” and the higher the R-value, the less heat escapes the home. Most conventional homes are estimated to be R-12 to R-20; most bale homes, R-30 to R-50. 

Isn’t straw flammable, you ask? Loose straw is, but bales are tightly compressed, and are no more flammable than wood. The National Research Council of Canada, for example, found that a straw bale wall withstood temperatures of up to 1,850 degrees for two hours.

Nor can the big bad wolf cannot blow the house down – the Building Research Center of the University of New South Wales, Australia found in 1998 that bale walls withstood winds up to 134 miles per hour – equivalent to a Category 3 hurricane.

The disadvantage to building with it is that it is quite sensitive to moisture, so here in Ireland it might be best to try it out with temporary structures – barns and sheds, for example. To find out if bale building is for you, consult books like “Serious Straw Bale” by Paul Lacinski and Michel Bergeron, or “More Straw Bale Building” by Chris Magwood.

If you don’t have the ambition for experimental architecture, however, you could plant a garden directly inside straw bales. I have heard from a number of gardeners who have tried this and swear by the result, and while they each used a slightly different method, the details were the same.

First line up bales, long side to long side, to create a garden bed, and water them as you would the rest of your garden for a few days. For a week or so after that, keep watering but add nitrogen and phosphorous -- stir some chicken manure in your watering can, leave it for a few days and pour the resulting liquid over the bales. Urine is also great to add, applied however you think appropriate.

After doing this for two weeks – just water for a few days, then water-with-fertilizer for a week and a half – punch a row of holes in the bales. Set a handful of rich compost into the hole, and plant a seedling in the earth. Sprinkle some earth on top across the entire top of the bale, and water as you would any other garden plants. The straw bale decays as the plant grows, until the plant can stretch more roots directly through the composting straw.

An approach like this can allow elderly and people with back problems to garden a raised bed without having to bend over all the time, and without having to build garden beds from wood. It helps make the garden unreachable by rabbits and many pests.

It helps cut down on the amount of soil you have to use, and since all soil contains weed seeds, it reduces the amount of weeding – although some of the grass seed will inevitably sprout. And, again, when the bales are disintegrating, they become compost, and nothing is wasted.

Wednesday 1 August 2018


Undated photo of children on an Irish train, courtesy of

Living on an island, the Irish have always been a nation of travellers, and some of my co-workers now fly to Majorca and Cyprus as frequently and casually as their grandparents travelled to Dublin. Now that money has become lean again, however, many are finding travel far too expensive to do frequently.

Strangely, there are several ways to travel cheaply that few people practice. One of them is the business trip -- my job paid for me to go to London three times in the last year, and each time I stayed on extra days to see the sights. My employer had to pay for a return ticket anyway so it made no difference to them, and I got to see London for several days.  

If your job doesn’t send you abroad, however, some airlines offer standby tickets, which allow you to take a flight as soon as a passenger misses their flight. If you don’t work full-time, you might try being hired as a courier, to accompany a package to a destination, and see if a company will pay for most of your plane service.

When you want to stay in another country, hostels are usually the best place to sleep. Most of them are as comfortable and clean as any hotel, but a hotel room might cost you a few hundred euros a night, while a hostel can cost you ten to fifty. They differ from conventional hotels in that they often do not offer single rooms, with the private showers, televisions and maids that most hotel-goers have come to expect. Instead, most hostels require visitors to sleep in rooms with several other people, but this is not as difficult as it might sound; most hostel guests respect the privacy and sleeping habits of others and, as they are spending the day working or having fun, use their rooms only for sleeping.

Hostels also offer the chance to mingle with other guests in a way that hotel s do not. Since most people in hostels use their rooms only for sleeping, and spend their time at the hostel sitting in common rooms, hostel guests have the opportunity to chat with others if they choose. Hostel guests also tend to be young and adventurous, often backpackers or other casual travellers, and come from all over the world. When I stay at a hostel, I soon have enjoyable conversations with people from Russia, Australia, Africa and many other parts of the world – all with stories to tell.

You might think that seeing a foreign city would be expensive, and every city is different. In many cities, though, the most amazing sites are the statues, buildings, rivers, bridges and public parks, and those are almost always free. London has dozens of museums, many of them open to the public every day for free; each time I go I see a few more. 

Many other great entertainments, however, are surprisingly inexpensive. Musical plays are in great demand right now, so their tickets run into the hundreds of euros, but amazing plays starring world-famous actors can have very cheap seats. I saw a play starring Keira Knightley and other well-known movie stars for about 30 euros, little more than a movie ticket with popcorn these days.

Travelling around a strange city can often be part of the adventure, and while most cities charge more than they should for public transportation, most also offer the opportunity to pay one charge for a whole day or week. The London Underground, for example, charges the equivalent of 8.50 euros to ride all day, but that takes one anywhere in the city for half the price of a short taxi ride.  

Finally, eating in another city or country doesn’t have to be expensive either. We tend to pay more for food when we are hungry, intuitively enough, and take less time to enjoy the food. If you want to eat cheaply and enjoy your food as much as possible, therefore, buy cheap, healthy snacks at a grocery store. Snack on fennel or apples as you walk or ride from one attraction to the next, and keep yourself from getting too hungry and impulsively buying food, and you will truly be able to enjoy the restaurants you do visit.
Tips like these can help you visit other parts of the world even on a tight budget – or, if you’re that kind of person, to save all your money for drinking.