Posts tagged ‘feature’
February 25, 2011
I established a black walnut Juglans nigra improvement programme while I worked with the Northmoor Trust in the mid 2000s. I was lucky to visit the USA on a couple of occasions as part of this work, where black walnut is an indigenous species and a significant timber tree.
I took part in two symposia of the Walnut Council where I presented papers. On my first visit, some of their leading researchers and growers laid on a fantastic tour across Wisconsin and Indiana. I visited the Hardwood Tree Improvement and Regeneration Center of Purdue University. I met over one hundred passionate walnut growers, including Senator Dick Lugar in Indiana, saw so many wonderful woodlands and was throughly looked after by fantastic hosts.
These visits laid the foundations for a black walnut tree improvement programme for the UK. Black walnut is economically one of the more productive broadleaved timber species in Britain. However, it is also one of the least-planted species. There was insufficient knowledge about the species among foresters and very little, if any, improved material was available.
I arranged a range-wide collection of seeds from plus trees and populations in the USA (Alabama, Illinois, Indiana, Iowa, Kentucky, Maryland, Minnesota, Missouri, North Carolina, Ohio, Pennsylvania, Tennessee, Wisconsin) and Europe (Austria, Czech Republic, France, Great Britain, Italy, Serbia and Montenegro, Slovak Republic). I planted two field trials in Britain during 2003/4: at Paradise Wood in Oxfordshire, and at the National Forest in Derbyshire.
Clark, J., Hemery, G.E., Russell, K. & Williams, H. The future of black walnut in Britain. Quarterly Journal of Forestry 99, 207-212 (2005).
December 10, 2010
If you are lucky enough to have a kitchen garden and to grow your own rhubarb, you should be aware that a danger lurks in the form of the walnut tree. Juglone, a natural but toxic compound found in walnut trees, will kill rhubarb as it is very sensitive to it.
Juglone occurs naturally in the leaves, roots, husks, and bark of walnut trees. Technically juglone is known as a phenolic compound. It is toxic to many other plants and it can also stunt their growth; it is extracted for use as a natural herbicide to control weeds. In a garden or forest its fallen leaves will create high levels of juglone in the soil, and a walnut tree’s roots will also release the toxin.
In the wild walnut fruit-forests of Central Asia, hundreds of thousands of walnut trees (Juglans regia) grow as the main canopy tree species without competition. One of the main reasons is the high levels of toxic juglone that has built up under their canopy. It is interesting that underneath the walnut trees, some plants do thrive particularly wild apple, pear and plum. You can read more about these forests in my Walnut Expedition Journal.
Juglone is also a very effective natural insecticide; a phenomenon observed by our ancestors. They may not have known about phenolic compounds but they recognised that horses tethered to a walnut tree would remain unmolested by buzzing insects. My view is that this is why there so many public houses in Britain named “The Walnut Tree Inn”: many of these will have been coaching inns – once a vital part of our transport infrastructure. A search on Google maps for “Walnut Tree” inn or hotel brings up hundreds of results across Britain.
November 12, 2010
Some years ago I had the privilege of visiting a leading maker of fine guns, James Purdey and Sons of London (Est. 1814), where I met their wood expert and buyer.
The common or English walnut (Juglans regia) is the wood of choice for gunmaking as it has superior strength and flexibility, and it holds tightly the surprisingly small screws that are used to mount the metal parts to the stock. The other quality in walnut is its beautiful figure of course. One gunmaker’s lyrical explanation of walnut figure captures it perfectly:
“mottles and motes, sunburst and fiddleback: as intricate as an opium dream.”
I was shown into Purdeys’ stockroom, an Aladdin’s cave containing thousands of beautiful wood ‘blanks‘; ready for the next customer to select their choice of wooden gunstock. The company go to enormous effort to source walnut of the right quality, with the emphasis on both beauty and strength. Today they source almost exclusively from the walnut forests of Turkey. Other sources have been used in the past but these have been either exhausted of suitable stock or proven to be too expensive due to access problems. Kyrgyzstan is a good example of the latter, where the mountainous terrain and poor infrastructure are significant barriers.
In the stockroom my eyes were drawn to one particular wooden blank that had been shaped and part-machined but lay amongst the thousands of other rectangular blanks on a shelf. It had beautiful figure and I wondered, aloud, why it has not been finished and used in a gun. The expert pointed out that though the figure was exquisite, the grain at the gun’s thinnest and most vulnerable point, the neck, ran across rather than along the blank. He explained that it had been shaped and machined to that point only because the customer was so keen of this particular piece of walnut. However, it could never be used as a blank as it would have been dangerously weak. He then surprised me saying “you can have it if you like?”
I was obviously delighted and have used it for years in talks and presentations. I polished one side of the blank to bring out the beautiful figure. Had this blank been perfect it would have been worth at least £10,000; if part of a matching pair over £25,000 for the two. This sort of value is rare in wood but of course Purdeys supply the highest end of the market where only the best will do.
October 2, 2010
The same year that I started planting Paradise Wood , a new forest and centre for forestry research in Oxfordshire, I started recording a view of the former arable farm from a nearby vantage point.
The Wittenham Clumps provided a perfect place to view the low-lying fields to the north, looking towards the village of Long Wittenham. The first photograph was taken in 1993. Unfortunately this did not include the entire width of the future forest although from 1996 onwards a full view is captured.
The photograph catalogue so far is 1993, 1996, 1998, 1999, 2000, 2001 and 2010. I am sure that I haven’t run this photomonitoring project as well as I should. The images don’t align exactly when closely compared. In my defense the fence corner post that I used to mark the position was removed sometime in 1998, and the format changed from 35mm slide to digital format too.
The pictures certainly make for a fascinating record of a changing landscape over a 17 year period, which I intend to continue.
August 18, 2010
I undertook an expedition to Kyrgyzstan in 1997 to collect walnut seeds from the wild walnut-fruit forests.
Walnut journal entry – Monday 29th September 1997
I woke up with a terrible stomach and I knew when we left Mamajan’s home at 0900 for another day collecting walnut seeds in the forest, that I was in for a bad day! Frequent trips to the bushes during the morning soon confirmed this and I felt increasingly tired and lethargic. After struggling around the first few trees the others decided that I should be abandoned! So I lay down on a small terrace on the hillside; underneath the spreading crowns of the walnut trees. Luckily some tablets I had taken calmed my aching stomach and I quickly fell asleep.
I slept for three hours – woken only once by an inquisitive feral cow breathing in my ear. The ‘crash-thud-crunch’ of walnuts falling through the canopy of leaves, hitting the ground and bouncing in the thick leaf litter, soon soothed me back to sleep.
When I woke for good I felt much better but still rather delicate. The others had worked splendidly without me!
Later back at Mamajan’s home, where the rest of the family had been busy bagging sunflower seeds, we decided that tomorrow should be a rest day. The day after we may travel the furthest yet to collect walnut seed; that’s bound to be a tiring day.
I found out today that the maps we had bought in Bishkek – the ones where I felt like a spy buying them – had ‘SECRET‘ stamped on each of them! I was right after all (more here).
June 22, 2010
I met the late environmental broadcaster and writer Roger Deakin (b. February 11th 1943 and d. August 19th 2006) when he came to visit the walnut trials I had established at Paradise Wood in Oxfordshire. He was researching for his book, Wildwood: a journey through trees, that would become his last, published in 2007.
Roger came to learn more about my walnut seed collecting expedition to Kyrgyzstan, and to see the walnut research field trials in Oxfordshire (Wildwood p. 148). He came as a member of the Walnut Club; a short-lived group dedicated to walnutters interested in growing walnuts for their fruit and timber, then supported by Horticulture Research International.
Our meeting led to him pursuing many in my walnut network including Robin Bircham in Suffolk, Peter Savill in Oxford, and Jaguar Cars: summed up in his beautiful prose in the chapter Among Jaguars. He later describes his own travels to Kyrgyzstan, including his explorations amongst the walnut forests in the south.