The last fortnight has been a little gloomy, with the first confirmed outbreak of Chalara fraxinea (Ash dieback disease) in mature ash in Devon. Fifty miles from Treragin and closing! I have been thinking about how to respond when (and I regret it is when, rather than if) the disease reaches us.
I included 30% ash when planting Treragin, 24 years ago now, which means around 1500 ash trees at risk. The other main species planted were southern beech (also 30%), oak (15% and wild cherry (15%), plus 10% mixed shrubs, mainly planted along the ride edges. I always thought firewood was likely to be a mainstay of harvesting, and so went for a mix of quality (ash) and speed (southern beech). Fortunately they tended to be planted in small groups, so nowhere is there a group of more than 25 ash trees. The southern beech has certainly romped away, with trunk diameters of up to 50cms; ash has also done well, and as you might expect oak has been the slowest growing.
In early thinning work I had been aiming to make sure that the southern beech did not swamp other species, and worked hard to ensure the survival of the best oaks. (I’ll leave squirrel control for another blog!) Now I am having to change emphasis and aim to thin against the ash, and in favour of all other species.
This will not lead to the loss of ash from Treragin, but a significant fall in its importance is inevitable. Current thoughts are perhaps 10% of the natural stock will be immune, so let’s hope on that front. Elsewhere I have often stressed the importance of an uneven structure for good woodland conservation, and it looks as if Chalara will help achieve that for me. How much replacement planting will be necessary remains to be seen, but if the roe deer co-operate there will be scope for some natural regeneration. Canopy spread from adjacent species as they continue to mature will also reduce any need for replanting.
So I guess things could be a lot worse, but after more than twenty years hard work its a little galling to face such a dramatic change. I may need a few more firewood customers!
Meanwhile, Kathryn, my wife, and I undertook the now annual count of orchids in Treragin Wood last weekend. Rather later than usual, because of the cold spring, though that is hard to imagine now. The main object of the count is broad-leaved helleborines, which are a relatively uncommon species found in shady hedgerows and woods. It is allso rgarded as an ancient woodland indicator species, though in Treagin’s case we think they have spread from the old hedge along the stream and bottom of the wood. This year we found 65 spikes, well down on last year, however last year was exceptional. The good thing is that we are now finding them throughout the whole 13 acres, whereas they were once along the bottom path only. I am sure there are many more than 65, but we do not have the time to walk over the entire wood. Two twayblades also made their standard appearance, in the same location for five years now.