It’s all in the genes

As August turns to September we enjoy the hot colours of summer: the tiger lilies; the red dahlias; the orange heleniums, the many salvias, and – new to the garden – the little bat-faced cuphea, Cuphea llavea ‘Torpedo’, which makes a low mound of bright red and purple flowers. The cuphea is a native of Mexico and its long, purple, hairy calyx and corolla tube gives a clue to its main pollinator – the humming bird. Whilst there are no pollinators with long enough tongues to do the job in Scotland, here the bees have bored holes in the bottom of the calyx and corolla tubes and stolen the nectar. The two red petals give the plant its comical name.

For the gardeners August is dominated by the cutting of the yew hedges. Nowadays it is facilitated by a Mobile Elevated Working Platform (MEWP). Mike and Steve are the main hedge cutters and they need to make good use of the MEWP because it is expensive to hire. However, this year it breaks down and for a while things are slowed up and ladders are used as they were in the past. But not shears! The cutters they use are electric which have the added advantages of being quieter than the previous cutters and being more planet friendly; the MEWP is noisy and still runs on diesel

Some of the hedges were not cut last year and the Scottish flame flower, Tropaeolum speciosum, became even more of a nuisance than usual. There is a love/hate relationship with this Chilean nasturtium – definitely part of the Crathes summer scene, but rather a trial when it has to be removed before cutting the hedges. By the beginning of September the walled garden yews are just about finished, but there are still hedges and bushes to cut elsewhere – some around the nursery area and some at the West Lodge.  

The egg and eggcup yew topiaries are thought to have been planted in 1702. For Crathes folk they are much loved; for visitors they have that ‘wow’ factor that makes a visit memorable.

They also have relevance in a national and international context. The Royal Botanic Garden Edinburgh (RBGE) is an important player in global conservation and it is one of the remits of the garden to preserve the genetic diversity of species wherever possible. Diversity is best preserved in healthy habitats and ecosystems, but with the planet in crisis there is an urgent need for conservation in seedbanks and in living collections. A project started some years ago by the International Conifer Conservation Programme (ICCP) is slowly coming to fruition with the planting of hundreds of yew trees, Taxus baccata, from diverse genetic origins, in the form of a hedge – the new perimeter hedge of RBGE. A cutting taken from the famous Fortingall yew began the planting in 2014; eventually around 2000 yews will be planted. When completed the hedge will contain cuttings from seventeen Scottish heritage yews; from eighteen English, Welsh and Northern Irish yews; and from two in the Republic of Ireland. It will also contain plants grown from seed collected from various locations within the natural range of the yew including two English sites and one Republic of Ireland site. Other locations within the natural range include countries such as Denmark, Albania and Croatia where RBGE staff (often nationals of the country) are domicile. A heritage hedge can successfully preserve a wide genetic diversity of one species in a relatively small space. In this case 30% are from the British Isles and 70% are from other countries. Why is this hedge important? With such a depletion of the natural habitats of yews, the possibility of declining health – in the way that inbreeding in humans is detrimental – might affect the long term future of these trees. If in time we learn to manage our resources more effectively, habitats may be restored and the diversity of the RBGE hedge will give any such restorations a greater chance of success.

The Crathes egg and eggcups are over three hundred years old and a cutting from the more southerly topiary has been included in the RBGE hedge. Also included is a cutting from one of the yews that grows about the crags just to the south-west of the castle – thought to have been planted around the end of the eighteenth century.

I was delighted to realise that I was familiar with some of the other yews that are represented in the hedge. The Fortingall yew, sometimes said to be 5,000 years old years old, is estimated by RBGE to be 1,500 to 3,000 years old and may be the oldest tree in Europe. It’s a long time since I was there – before the days of digital images. For centuries this yew has been a tourist attraction; the protecting wall surrounding it dates from the late eighteenth century. The Selborne yew and the Kingley Vale yew wood were seen when we spent a holiday in the South Downs in 2015. A highlight (there were many) of that holiday was a day spent visiting the gardens of Jane Austen and Gilbert White the famous naturalist (1720-1793). In the churchyard at Selborne I was fascinated by the enormous stump of the ancient yew which had blown down on 25 January 1990. The tree was torn up in the gale and it was decided to cut the crown back and replant the massive stump. Cuttings were taken at the time and one is now successfully growing in the churchyard, but the parent tree was later pronounced dead. It appeared to re-sprout in 2008, but it is thought that the sprouts are seedlings, not clones of the parent tree.

I discovered that Gilbert White mentions it in his book, but I couldn’t find the quote in my copy, although there are a few attractive illustrations of the church and its famous tree.* Then I realised that the ‘Antiquities’ section is not included in all editions. This is White’s comment which I found in the online Biodiversity Heritage Library: In the church-yard of this village is a yew tree, whose aspect bespeaks it to be of a great age: it seems to have seen several centuries, and is probably coeval with the church, and therefore may be deemed an antiquity: the body is squat short, and thick, and measures twenty-three feet in girth, supporting an head of suitable extent to its bulk. This is a male tree, which in the spring sheds clouds of dust, and fills the atmosphere around with its farina.

Yews are dioecious – male and female cones are generally born on separate trees – although trees do sometimes change sex. The single seed is surrounded by a red fleshy scale which looks more like a berry than a cone. The Fortingall yew is male but recently developed a branch that is female.

Another day in the Downs we visited the Kingley Vale yew wood just to the north of Chichester – the largest yew woodland in the British Isles.

Some of the yews at Crathes are Irish fastigiated yews – growing tall and straight – and I was interested to see that cuttings of the Florence Court Irish yew in Enniskillen have been incorporated in the heritage hedge. The story of the Florence Court yew dates back to 1767 when a local farmer, George Willis, collected two saplings from a nearby mountain. One he gave to Florence Court, the other, which he planted in his garden, later died. The Florence Court yew – a female – thrived, many cuttings were taken and all the Irish yews in the world are thought to have originated from this one tree. Any seedlings derived from the berries revert to normal spreading growth; the cuttings preserve the genetics.

I did wonder if the Hampton Court yews might be incorporated in the hedge, but no. However, I can’t resist including them in my reminiscing about yew trees. They had been planted as avenues in the Great Fountain Garden created for William and Mary about the same time as the egg and eggcups were planted at Crathes. The story goes that sometime later Lancelot Brown (c 1716-1783), famous for developing the English Landscape tradition, allowed the yews to grow naturally. I love their, now clipped, unusual shapes.

Martin Gardner, Co-ordinator of the ICCP, has given me information on the RBGE hedge.** He says they are now planting the last part of the hedge with trees he collected in Morocco some years ago. Martin is writing a book about the hedge which will include information on each yew from which they collected material.

The yews at the north end of the Crathes Millpond were probably planted in 1858 when the Millpond was developed into a decorative feature as the East (main) Drive was established. Before that the millpond had been purely functional and part of the Candieshill rental.

When I was nosing about around the yews at the millpond I saw some interesting fungi. The white fungi seemed to sprout where broadleaved tree trunks were lying rotting – often following the line of the trunk.  Less welcome was the sight of the invasive skunk cabbage; there were more along the side of the Coy Burn.

The rain following the heat has brought forth a crop of different fungi. There are few species that I am confident to identify, but I find them beautiful and intriguing so will just post a few photographs.

Genetics came up again when I was talking to Joanna about the Aeonium tabuliforme that is flowering in the broadspan. This plant is fasciated – ‘when several contiguous parts grow unnaturally together into one’ (Oxford English Dictionary).

I remembered that when the original plants flowered one of them was fasciated, and so we wondered if some of our collected seed had originated either from the fasciated plant or from seeds pollinated by the fasciated plant. An online article suggested fasciation can be caused by recessive genes.***

My computer auto-corrected fasciated to fascinated; checking on the spellings and usage of both fasciated and fastigiated I realised that I had often mixed them up and used them incorrectly. Since we have plants of both types of growth in the garden I soon had the words sorted out. The Dawyk beech that grows in the Golden Garden is a good example of a fastigiated plant; its branches, like the Irish yews, all growing upwards. It was found around the mid-nineteenth century in the grounds of the Dawyk Estate, near Peebles, (now belonging to RBGE). It was moved nearer to the house and a later owner dispersed cuttings to the botanical world.

Confusingly the Veronicastrum virginicum ‘Fascination’ that grows in the Blue and Pink Border and in the Upper Pool Garden is often fasciated.

More issues of genetics arise as we contemplate the Portugal laurel in the centre of the White Border. We don’t know its age, but it is well over a hundred years, perhaps two hundred years old. For some time the head gardeners have worried about it. Now hollow and looking rather thin on top the time to replace it cannot be that far away. The regrowth at the bottom shows us that it would not die if the top was blown over, but its position in the garden calls for a more immediate solution.

Many years ago a new plant was raised from cutting of this tree and planted in the gardener’s garden until such time as it was needed, but the years went by and the young tree is now too big to transplant. Another solution awaits in the yard because the cuttings that Joanna took in 2019 have grown amazingly. True, they could do with being a little bigger, but should there be an emergency the new cutting, which will have the same genetics as the old tree, could easily take its place.   

Updates

Work continued on the drains with James and Davy shifting about 40 tonnes of hardcore to improve the camber on the path to the garden. Larger drains and silt traps are also to be installed and it is hoped that the long-term problems of flooding at the gate will be sorted. In the garden there has been a concentrated effort to improve the paths.

At last we have some butterflies with peacocks enjoying the buddleias, but it has been a worrying year for insects with few of the usual solitary bees in evidence.

There is definitely a feeling of autumn in the air now and the plants confirm the turning of the year. Autumn crocuses and nerines are in flower, the crab apples are making a show, viburnum and enkianthus berries are ripening as are the conkers on the horse chestnut trees.

*White, Gilbert, The Natural history Of Selborne (Ware 1989) illustrated by Edward H New; first published in 1788-89.

**Conservation Hedges – Modern-Day Arks in ‘Sibbaldia’ (Journal of Botanic Horticulture) No. 17 pages 71-100.

***Annals of Botany, October 2006; 98(4): 715-730.