The grounds of the Astley Ainslie hospital, excluding the spruce plantation at the south end, contain around 1000 substantial trees. These trees give the site much of its attraction, visually and as an open-air space where people can walk, play and exercise. And it is largely because of the trees that the site accommodates such a variety of wildlife.
The trees on the site are protected under a Tree Preservation Order, which has been in place since 2000. The schedule relating to the order is based on a survey undertaken by R.H. Watson in 1998, attached to the report of which is an evaluation of the ‘character and quality of the treescape’ (October 1997) by Alistair Scott.
The 1998 survey lists 814 trees having a trunk diameter of 30cm or more, and a further 413 smaller ones.
Alistair Scott’s assessment of the ‘treescape’ very largely still holds good. He describes its components and suggests when they would have been planted and for what purpose. The oldest trees probably date from the early 19thcentury, but it is likely that most of the larger trees that form the bones of the present landscape were planted after 1850. Scott suggests that one of the oldest trees is the Spanish chestnut in the grounds of St Roque. Its base was formerly encircled by a seat held in place by three cast iron dragons, but only a small embedded iron fragment remains.
The commonest trees on the site (around a third) are sycamores, and many of these will be self-sown, originating from several very large old specimens in the SW corner. But the trees that probably contribute most to the structure and character of the landscape are limes. There are some particularly fine old specimens on the western boundary, in the thicket between Canaan Park and Grange Loan, and in the grounds of Woodburn House, which also have some of the tallest trees of other kinds. There is a large silver pendent lime in the Canaan Park thicket (close to two very large Norway maples) .
Four species of oak are present, five if you count the young North American oak in the grounds of Woodburn, and there is a large tree E of the modern detached building on the Woodburn site that may well be a sixth. There are large and conspicuous holm (evergreen) oaks in the grounds of St Roque and Canaan Park and there are several Turkey oaks close to the W boundary of the site in what would have been the grounds of Millbank (another with deeply dissected leaves sits beside the road below the Grange Loan entrance). Also in the grounds of Millbank, closer to the Administration Block (originally Canaan Cottage), is a group of three oaks – Turkey, English (pedunculate) and sessile, which is the one that occurs more commonly throughout Scotland. There are, however, relatively few native oaks on the site, and they are missing altogether from Scott’s list.
Among other kinds of native trees, there are a few scattered Scots pine – generally of no great size. Most of the pines on the site are Austrian pines (called Corsican pines by Watson), easily distinguishable from Scots pines by their dense tufts of darker green, long, stiff needles. The only other type of pine present is the Bhutan pine, of which there is a massive specimen in the lawn in front of the Administration Block; Scott suggests this is probably the largest one in the Lothians. There are two or three more of these to the E of the school building but they are rather hemmed-in among other trees. The Bhutan pines are easily recognisable by their cones – roughly the size and shape of a banana – and their floppy needles in bundles of five (rather than two).
Other notable conifers include cedars, two giant redwoods, two Coast redwoods (sequoias) in the grounds of Woodburn House, and the silver (noble) fir in the open ground to the S of St Roque. The giant redwood beside the road that runs up to the Charles Bell Pavilion to the W of the school is perhaps the most striking tree on the site, at around 30m high and with a girth of approx. 6m. There are at least five kinds of cypress present, although the great majority of the cypresses are various forms of Lawson’s. Some of these, perhaps most notably the ones beside the Administration Block and in front of Woodlands House, are nicely proportioned and visually quite striking. The large trees in the woodland below Woodburn House, on the other hand, are very much smothered by their surroundings. Close to the main traffic roundabout there is a single, very substantial Monterey cypress. These are commonly planted in seaside towns on the S and W coasts of Britain and Ireland because they resist the wind and salt spray, but they are infrequent in Edinburgh. There is a single monkey-puzzle, to the SW of St Roque – close to the chestnut but somewhat suffocated in the belt of trees. And there are two Douglas firs, strikingly tall but thin and straggly, in the belt of trees separating the grounds of Millbank from Canaan Cottage.
The commonest of the cedars is the deodar or Indian cedar – there are two particularly large ones between the disused Sycamore Block (on the Millbank site) and the Administration Block. All three kinds (the others are the cedar of Lebanon and the Atlantic or Atlas cedar) are present as large trees lining the road between the roundabout and St Roque in a very stately order. The Lebanon cedar here has been badly damaged by the wind, as has the one in the woodland behind Woodburn House, but it is still easily distinguishable from the Atlantics and deodars by its stiffly horizontal branches. A young Atlantic cedar with strikingly pale (‘blue’) foliage in front of the Administration block was planted in memory of George Bald, a hospital gardener. Another, in front of the occupational therapy building was allegedly planted to mark the end of the Second World War (VE day). Quite close to it there is a young-ish specimen of Metasequoia glyptostroboides, the (Chinese) dawn redwood, which may also have been planted to commemorate a person or an event.
In the relatively open part of the site around the main treatment blocks there are Japanese flowering cherry trees. It has been suggested that these – like others in Edinburgh – were planted to mark VJ day. But many of them are clearly rather older than that, and they were more likely planted when the pavilions (wards) and the Scientific Block were built. Two weeping willows just east of the Scientific Block are a pleasant feature of this area; there are two more of them close to the school building. And there is a single Himalayan birch with bright white bark in front of the WRVS café.
The plantation between the modern Smart Centre (opened 2007) and the railway is seemingly not covered by the Tree Preservation Order. It consists almost entirely of Norway spruce (Christmas trees), unlike most of the plantations in the Southern Uplands, in which Sitka spruce overwhelmingly predominates. It contains an active badger sett.
The strip of ground between the plantation and the railway, where the Jordan Burn runs underground, is damper than the rest of the site – with a few characteristic plants such as the great hairy willow-herb and tussocks of the pendulous sedge. On the very edge of the plantation there are three white willows, one blown severely askew by the W wind, and there are one or two sizeable sallows on this part of the site. Hard against the W end of the plantation are two unusually tall pear trees which produce small, rather globular and bullet-hard pears.
In the gap between the W end of the plantation and Egypt Mews is the only patch of what might be considered wild grass, albeit surrounded by brambles and nettles. This has an assortment of characteristic wild flowers that might once have occurred much more widely across the site and indeed in the local area: meadow buttercup, field scabious, tufted vetch, birdsfoot trefoil, bush vetch, and the smooth tare. There is also a single plant of the common spotted orchid.
One more plant worth mentioning: a large specimen of pokeweed grows just above the main car park where the path comes through the wall from the Balfour Pavilion to the workshops. I am reasonably certain it is the Chinese pokeweed (Phytolacca polyandra) rather than the American one. This is a poisonous plant that grows to about 6ft and it does look just a little menacing in the autumn, with long spikes of black berries carried on pink stems. Pokeweeds have various real and imaginary medicinal properties and it would be nice to think that it has come from the garden of James Syme, the surgeon who lived at Millbank from 1842 -1870 where he kept a physic garden.
Reproduced by kind permission of the Astley Ainslie Community Trust