This Week features the Bee-wolf (Philanthus triangulum). We appear to be in a peak period of nesting for this fascinating solitary wasp. Previously considered rare, they have rallied in recent decades. The bee wolf is a member of Aculeata, one of three super families of the ‘Stinging Hymenoptera’. The defining feature of all aculeates is that the egg-laying ovipositor is modified to form a sting. In Britain there are around 590 species of aculeates. These include ants, bees and wasps.
For more than a quarter of a century, entomologists from the Natural History Museum have visited Barnes Common to research Aculeata, a fact discovered by chance when our Education Manager was visiting the museum on another matter! The bee wolf is just one of more than a hundred species of Apoid wasps found on the Common. Twenty-five are described as locally rare or endangered and is one of the reasons you will see some areas fenced off.
Two people alerted me to a ‘swarm of wasps building a nest’. On investigation I was happy to explain to the family that it was in fact just a hundred or so bee-wolfs and that the sandy south-facing scrape on Mill Hill was the perfect place for them to set up home. They will catch another insect (often a honeybee, hence their wolf name) as their prey, insert it in their nest hole and then lay their eggs on it, so the hatched grubs have a source of food. Other solitary bees and wasps will dig in the ground, making little volcanoes of sand – about an inch across and half inch high. Once you get your eye in you will see them everywhere around the Common through most of the summer.
HAZEL (Corylus avellana) is the first of our featured trees this week. It is a member of the Birch family (Betulaceae) that also includes alder, birch, and hornbeam. This native hazel was probably one of the first to recolonise after the retreat of the glaciers and may even have survived in small areas. Hazel in the UK is typically a shrub, with many stems and rarely a single trunk, but this may in part be due to coppicing and/or grazing. Although some claim it only grows to 6m and others say 10m, we have one tree on the Common which has multiple trunks but has grown to this sort of height – making it arguably our most Notable tree. It has probably been left untouched since being coppiced some 150 years ago. Hazel is known for its ‘lamb’s tail’ (male) catkins – early signs of Spring. Its fruit is hazel, or cobnuts. Here on the Common these are most likely to be eaten by squirrels long before they are ripe (if insects have not got there first).
Hazel supports over 100 insects. Over thousands of years it has found its place in planted hedgerows and woodland. Anyone planting a quickset hedge of thorn would be wise to include hazel in the mix as this ensures a ready supply of stakes every ten to twelve years, which is invaluable in laying the hedge. Hedge-laying is the highly skilled craft of bending and partially cutting (pleaching) through the stems of a line of shrubs or small trees near ground level and arching the stems without breaking them, so they can grow horizontally and be intertwined. There are many different styles of hedge, dependant on where you are in the country and this is a great source of pride to local craftsmen.
Coppicing and pollarding are two ways of extending the life of a tree – Oliver Rackham estimated one coppice stool to be over 1500 years old, ten times its normal lifespan. This type of woodland management also increases biodiversity in the woodland understorey and floor. We are fortunate to have a small hazel coppice on the Common, planted some 25 years ago and now on its second rotation. Hazel propagates easily by striking cuttings or layering (pegging a shoot to the ground). This was done during the first coppicing, to produce many new whips for transplanting into our new hedges. We hope to see these woodland management techniques and crafts promoted over coming years.
Fast-growing and easy to work, coppiced hazel gives a good yield and as many traditional uses including bean poles, clothes-line props, hurdles, baskets, thatching spars, pegs, barrel hoops, and cropping for fodder. As I discovered, hazel makes the best rods for water divining, the perfect little white wood ‘Y’ we needed at school as our locker peg, and passable bows and arrows. How we children enjoyed the hedge my mother planted to supply her bean poles!
LIME is our second featured tree this week and belongs to the large Malvaceae family that includes Cacao (chocolate), Kapok, Baobab and Durian trees, as well as Okra, Cotton, Hibiscus – and Hollyhocks!
The Common Lime (Tilia x vulgaris, aka T x europea) is a hybrid of Britain’s two true natives, Tilia cordata and Tilia platyphyllos (small and large-leaved limes, respectively). The Common Lime can also be native in areas where both parents exist and natural hybridisation occurred, but most derive from trees imported from the Netherlands, when long avenues became fashionable in the 17th century. The name is likely a derivation from Lind or Lyne, forms of which are found in German (linden), Dutch, Norse, Old English and in a North American children’s song: ‘…you rake the linden leaves, I’ll rake the ash. Red leaves and yellow leaves burn in a flash’. Perhaps appropriately, on the Common, we have Common Lime. All have been planted.
Spreading north some 8000 years ago, before the English Channel was formed, Lime was a dominant species in primeval woodland, more common than Oak, with small-leaved lime more abundant than the large-leaved. Today it is almost impossible to capture a sense of how this woodland might have looked. Like other trees, it was coppiced for winter fodder.
The Common Lime grows tall and can form imposing avenues. However, with age its limbs die back and it can begin to look quite scruffy. Its sweetly scented flowers appear quite late, attracting many bees and insects: I have seen a bee swarm take up residence on a lime near the railway when it was in flower, moving on after a couple of days. It has often been planted along roads, but it is a poor choice as it is prone to sprouting at the base of the trunk (epicormic growth), which blocks paths and requires maintenance – as along Vine Road. Older trees shed heavy limbs with potential for significant damage. However, the trees also support vast numbers of aphids, with the sticky honeydew an asset for more than fifty insects, lady birds and small birds – but not so much for any cars or anything else below!
In pre-Christian time, large and small-leaved Lindens were associated with Frigga, the goddess of fertility, danced around and served as a trysting place for lovers meeting under the shade of their heart-shaped leaves. They were often planted to celebrate religious or civil liberty, or the end of wars. The wood was used for bowls, ladles, and dug-out canoes. The under-bark, known as bast, was stripped and the fibres used to make robes and nets in prehistoric times.
22nd June 2020. M Hildesley
Images unless stated: M Hildesley
 MILNER J E; (1992) The Tree Book Collins & Brown: London