Chestnuts roasting on an open fire ……… the lyrics and scene fill us with nostalgia for chilly autumn evenings, family and friends together, chatting and telling tales – long before the invasion of the tele! Thus an ‘old chestnut’ became a tale told once too often! Autumn evenings here would not be the same without the street sellers’ glowing braziers serving finger-burning castañas.
The sweet chestnut, castanea sativa, or Sardian nutis native to Sardis in Asia Minor. It spread through Europe, self-sowing, on climatic parameters roughly equivalent to that of the grape vine. The mighty Roman Empire gave the tree a huge thrust into the British Isles.
The nuts were an important food crop in Southern Europe during the Middle Ages when forest dwellers, with little access to wheat, ground the nuts down into a carbohydrate-rich flour. They were also boiled, roasted and candied – as in the world famous marrons glacés. The crop was stored in sand-packed barrels so that maggots had to surface for air, where they were killed.
The sweet chestnut is one of the most magnificent of our European trees, attaining 30m in height and with a stout, solid trunk and spreading branches forming a large leafy canopy. Happy wherever soils are light, with some humidity in the air and fresher night-time temperatures – it is one of the stalwarts of our Mediterranean foothills. Look for them now – they’re very distinctive with their prickly nutcases, like large green sea urchins, held in twos or threes, which split open to reveal the glossy chestnut-brown nuts inside. The bark is greyish, grooved and fissured, twisting round the trunk in spirals that resemble worn rope. The large handsome serrated leaves turn a delicious golden yellow before leaf fall. One of our last trees to flower, it produces catkins, some male only, some with male and female on the same branch. They’re striking but the males give off a heavy, sickly-smelling pollen which many find overpowering. They can take several years to settle into nut production and are considered mature at thirty years of age going on to bear crops for very many years – often living for centuries.
The wood is oak-like, but more workable. Because of its tendency to split and develop deep fissures, it was used for smaller decorative items, for building and mine props, and barrels. Coppiced plants were used to produce chestnut paling and, by the brewing industry, as stakes for hops.
Although it is such a large tree, the roots are not particularly invasive. Give it space simply because it’s large and majestic, and it deserves it!
The walnut, or juglans regia, a native of Persia was, again, spread through Europe by the Romans. It’s a rapid grower, often attaining 20-25m with large, stretching limbs some 10m long. A strong tap root anchors it into even the rockiest ground and enables it to reach a great old age though, like the chestnut, it can take a few years to come into production. Its timber, beautifully veined, is noted as being, proportionally, the lightest to strength of any other known; it was used for gunstocks and in furniture and piano making. The roots, bark and unripe husks of the nuts produce a dark brown dye – take care when harvesting! The young, unripe fruits are often preserved as sweetmeats or pickled, whilst ripe nuts are important in autumn and winter deserts. My 5 year old grand-daughter longs for winter evenings sitting around our wood-burning stove cracking walnuts! Walnut oil is pressed from the kernels, giving half the weight of oil to kernels. For harvesting, the trees are beaten with long poles (similar to olive cropping). This often breaks the branch tips which will then produce new spurs and female (fruit-bearing) flowers. This thrashing of the tree is also applied to barren trees to bring them into production.
In hot weather, or when bruised, the leaves give off a very powerful narcotic aroma which produces drowsiness, so take care not to fall asleep under the shade of your walnut tree! Even more importantly, don’t even try to grow anything under your tree – it is one of the most allelopathic plants known to us – which means that it gives off a chemical, juglone, to ‘protect its space’ and even grass will not grow under a walnut tree.
Once established neither tree will need irrigation, they are very disease resistant and undemanding trees. They’re not, perhaps, trees we would think to plant in our orchards or as large specimens but, when you do, I know you’ll be proud of them!
Lorraine Cavanagh has lived in Spain for over 21 years; a mother, grandmother and hispanista, her passions are plants, the environment, food and drink, and travelling within Spain. She owns a small plant nursery, is a landscape gardener and a writer. She also has a weekly spot on OCI radio. Her book Lorraine Cavanagh’s Mediterranean Garden Plants has been nicknamed ‘the bible’ and it is now generally available throughout Spain. Flexi-cover €24 and hardback €31
E-mail: florenaspain@hotmail.com
