Research into the varieties chosen for the Tree Trail
One of the questions that is often asked is why the trees we considered led to those we now finally see in the tree trail - How did we choose them ? What were their characteristics that led them to be preferred above so many other varieties ? Perhaps especially why some of these trees are not native varieties and should non-native have been prioritised for consideration. The phrase “The Right Tree in the Right Place” is behind everything in the trail - whether it be a tree to cheer us all up in Winter or to provide the longest flowering season for pollinators; as well of course our awareness of the urban environment into which our trees are placed.
The main starting places for these questions lies in three main places;
> one is how the residents and visitors to the town would benefit from seeing these varieties at different times of the year;
> another would be how well the varieties have been suited to the urban environment in which we have placed them - whether their root structure would be invasive, whether their seeds and fruits would present problems for pavements and if the seeds would self germinate and create problems within the generally limited spaces we have selected for their positioning;
> a third would be how beneficial the trees selected will be to wildlife, to the people living with them and how they might contribute to the local ecology.
To do this it was sensible to take all the advice possible and as varieties were considered they were discussed with both the nursery arborists and with tree specialists in Dorset.
Two academic researchers were ;
Dr Andrew Hirons; a Senior Lecturer at University Centre
Myerscough in Lancashire who teaches on full-time and online
courses in Arboriculture and Urban Forestry - and with a specialism
in tree biology and arboricultural practices.
and
Dr Henrik Sjöman; a Senior Researcher at the Swedish University
of Agricultural Sciences and Scientific Curator at Gothenburg
Botanical Garden. His work mainly focuses on developing
knowledge of site-adapted plant use for urban environments.
Starting with the accepted fact that climate is changing we needed to look at how resistant to drought our trees should be; how attractive they would be to visitors and residents; how supportive of wildlife they would be - all of course along with the mature size of the trees.
Each of the trees has a short hyperlinked comment outlining the reasoning for its choice.
Tree #1 - Prunus subhirtella ‘Autumnalis’, In the depths of winter what better mental lift can we get than to see flowers on bare branches and what better start for insects than early blossom in the spring and support for birds with berries in the autumn - all combined of course with stunning Autumn yellow colour. Prunus subhirtella ‘Autumnalis’ originated in Japan and came to the UK in 1894. It was given the prestigious Award of Garden Merit by The Royal Horticultural Society in 1930 and is one of the few trees flowering during the cold winter months.
Tree #2 - Himalayan Birch - ‘Snow Queen’. Himalayan birch is one of the climate ‘at-risk’ genus we chose - but in this case it was for the stunning platinum coloured bark rather than its environmental status. Our Wimborne Tree Trail of course is a part of the ‘Queens Canopy Initiative’ and that is a part of the Platinum Jubilee celebrations of Her Late Majesty, Queen Elizabeth II. The multi-stemmed variety (Betula utilis jacquemontii ‘Snow Queen’) was chosen to maximise the bark and to reduce the ultimate height of a variety that can grow quite tall.
Tree #3 - Koelreuteria paniculata. June, of course is the month of the Folk Festival in Wimborne and June/July is the time when the yellow racemes hang from the branches. These are heavily worked by Honeybees and Short-tongued Bumblebees for Nectar and also, but not so much for Pollen. The tree is a major source of nectar in July and August. How pleasant to sit in the early Summer on the grassy lawns outside the Allendale Cafe and the main house watching the flowers moving in the breeze. The flowers in turn give way to lantern-like seed heads that decorate the tree throughout the Winter months like delicate Christmas decorations; hanging on through all the winter winds and the rain until the new leaves appear in the spring time.
The winter interest helping to lighten our walks in the short winter days when the sun sets so early. The tree is happy with the dry conditions we have experienced in recent Summers and in our temperate climate gives no problems
Tree #4 - Styrax japonicus, Styrax japonicus would make an interesting and unusual tree for small gardens. Its wide, fan-shaped branches are covered in Summer with cascading trailing white bell shaped flowers and here on the small grassland area at the corner of two suburban roads this flowering tree makes a pleasant relief from the hedgerows and the older and upright limes that line the road lower down the hill. The flowers of course making it especially bee-friendly throughout the hotter Summer months. As the tree matures, the older dark grey and grooved bark reveals an orange under layer - allowing even the bare tree to contribute to the Winter scene.
Tree #5 - Sorbus Commixta, Chosen by the volunteers and trustees of Walford Mill, the Sorbus may be familiar to many residents and visitors - it is a relative of the ‘Mountain Ash’ or ‘Rowan’ - although this variety (Sorbus commixta 'Nanakamado' - also know as the ‘Japanese rowan’) is a little more unusual and originates in Japan; as its name implies ! It was the variety chosen for the London Olympic park surrounding the stadium and the leaf shape and colour has given it the name “Olympic Flame”. Flowering in May and June, followed in the Autumn by clumps of bird-friendly berries, the more common Rowan with which we are familiar was some of the trees to colonise the wasteland tundra after the retreat of the ice sheets 10,000+ years ago. The family of our more common ‘Mountain Ash’ trees have historical interest in communities too - often called "the witch" in England and used for dowsing rods to find ores. Twigs were also used to drive cattle to pasture for the first time in spring to ensure their health and fertility and in celtic folklore rowan trees were planted in pastures and on village greens to protect the nearby community from evil. [Read more]
Tree #6 - Gingko biloba (‘Saratoga’) Chosen for its awesome autumn colour and for the fact that it is on the endangered varieties list. It is therefore given a high priority conservation status, using the Evolutionary Distinct and Globally Endangered (EDGE) method. The tree has existed for the last 60 million years in its present form and is now the only one in its genus - prior to the end of the Cretaceous period there were related varieties back to 170 million years. The species revival has occurred through intervention by humans - and most interestingly it is one of the most effective tree at sequestering carbon from the atmosphere. As Carbon dioxide levels have risen research has shown that the tree adapts it’s leaf structure to absorb more and convert it to carbon within the tree - perhaps therefore the ideal tree to be planting in urban areas.
[https://ecobnb.com/blog/2019/03/anti-smog-trees/]
Tree #7 - Magnolia brooklynensis (‘Elizabeth’) In the Jubilee celebration year of 2022 the Queen’s Canopy Initiative was created. Her Late Majesty Queen Elizabeth II is remembered now especially with this variety named ‘Elizabeth’. Yellow magnolias are far less common than the pink and white varieties and produce a refreshing display in the springtime, although if a magnolia is planted in an environment it likes it can flower more than once in a season. In the wild, Magnolia are threatened mainly by timber production and by conversion of their woodland to open land for agriculture and livestock farming - all leading to a significant global decline in the wild.
Although not a native to the UK it was introduced in 1734 as a specimen tree - and that is how we are using all the trees on the Wimborne Minster Tree Trail. Traditionally the Magnolia tree symbolizes luck and stability and they have been around for a considerable time in parks and gardens here in southern Britain.
Tree #8 - Davidia Involucrata (Dove Tree) This medium sized tree has globe-like flower heads consisting of numerous male flowers and one female with a light green pistil and few stamens. The flowers are protected by two, and occasionally three, papery bracts - and it is these that give the tree its numerous names. When they first appear the bracts are green, allowing them to photo-synthesize but they gradually turn white and begin to attract a variety of pollinators. The most important of these are pollen-collecting bees and research has shown that insects generally prefer to fly to the white, rather than the green bracts. The bracts also protect the flowers from heavy rain and from strong winds - and in our variable and apparently changing climate this extends the life of the pollen sources. The three to four centimetre long drupes that form usually remain on the tree longer than the falling leaves and so add interest well into the Autumn.
Tree #9 Cercis canadensis (‘Forest Pansy’) Redbud (Cercis) trees flower early in the spring with a display that can last for several weeks - they can even last into June or July, depending on how hot it gets during the summer months - and so provide an attraction not only for those early butterflies and bees, but also the main groups later in the year. This particular variety (Forest Pansy) has large leaves up to twelve centimetres in width, that are a deep red-purple and turning shades of orange, bronze and reddish-purple in the autumn. The small, bright-pink flowers appear in clusters on bare stems before the leaves in spring; followed by the striking foliage that develops throughout the later summer giving a range of greens and purples ending with a blaze of reds, golds and purple hues. Its roots are kind to pavements and nearby brickwork; a prime consideration in an urban setting - and the shade it will provide on this small area of grass should prove useful for anyone waiting for family or friends who may be collecting the car or dropping it off in the adjacent car park.
Tree #10 Parrotia persica ‘Bella’ (Persian Ironwood) The ‘Ironwood’ is drought and heat tolerant and significantly free from pests - and with its flaking bark, its intense display of dense red ‘Hazel-like’ flowers on the bare branches in March it makes a welcome addition to any urban scene. The tree is not officially endangered in the wild; although it is seriously threatened, as it only comes from a very small area near the Caspian Sea that is gradually being converted to farmland. The ‘Ironwood’ is not a newcomer to our shores having arrived in 1840. It is a showy tree with reddish leaves in the springtime, gradually turning to dark green in the summer - having wavy edges for added interest - only to revert to yellows, reds and purples in the Autumn. Herbalists have used the species in earlier times for the treatment of various fevers and respiratory infections and it is also used for food colouring and food flavouring. It was first collected by the German naturalist, F.W. Parrot, on Mt Ararat while he was searching for Noah's Ark.
Tree #11 - Chitalpa taskentensis (Desert Willow) If we wished to have a small to medium attractive flowering tree that was also good to give dappled shady spots - just as might be required for a river-bank picnic - then it was obvious we would consider the fairly unusual Chitalpa tree. Since we also have a lovely grassy area beneath, then you'll be pleased to learn that it will thrive beneath the Chitalpa’s canopy. The long flowering season of this sterile variety has the twin benefits of providing pollen for a very long time - and so is bee-friendly over the whole summer - and yet provides no seeds that might germinate and create an unsightly area of an unwanted under-story.
In our changing climate that seems to be giving drier summers with wet and windy autumn periods, the Chitalpa can tolerate dryness and once established seems indifferent to wet spells too. In the autumn, the glossy green leaves turn golden and in the winter, the tree's attractive silvery-grey coloured bark will provide additional landscape interest - and remind us too of the 2022 platinum jubilee celebration for which it was planted.
Tree #12 Lagerstroemia - fauriei -Tuscarora (Crape Myrtle) When a
tree is found that can brighten up everyone with its vibrant and exotic colour why wouldn’t we choose it for the last tree to plant on our tree trail celebrating the 2022 Jubilee of Her Late Majesty Queen Elizabeth II.? The tree has been planted in England since the 1700s and as the English summers in recent years seem to be getting warmer , it may well start to be seen in many more gardens and parklands across our southern coastal areas. It is of incidental historic and botanic interest as Swedish merchant Magnus von Lagerstrom (from whom the tree gets its name) supplied botanist Carl Linnaeus with exotic new finds in the world of plants in the 1700s - including this species. It was Linnaeus who originated the plant classification system used in modern taxonomy.
The tree has fine roots that won’t damage pathways and nearby brickwork structures, so here alongside the Flood Defence wall it should be a kindly addition. And for anyone using the benches on their walks to and from the town centre - alongside the beautiful crystal clear River Allen it might be even more welcome giving both shade and colour.
There were concerns that it may not be frost-hardy enough here alongside the river but perhaps its worth taking that chance with so much benefit should it thrive here. The tree nursery from which it came is in Cambridgeshire and surely our climate here in Dorset will be kinder than the bleak fens alongside the North Sea ! We shall see.
Town Map
