Plant a Tree for Wildlife!

by Natasha Shirley

It’s autumn again and this is the perfect time to plant a new tree or shrub. Fears of selecting the ‘wrong’ tree or planting it in the ‘wrong’ place put people off from doing so. However, even the smallest garden or courtyard can accommodate some sort of tree and there will be a tree for you …

The benefits a tree can bring to our garden wildlife are numerous. Not only do trees bring vertical interest to our gardens, they provide a whole ecosystem of their own. Their foliage is a place of safety for birds to flee, roost and build nests, and their blossom provides nectar for bees and other pollinators.

Their fruits, nuts and seeds are a larder of plenty for the winter months; the leaves are larval food for butterfly and moth caterpillars; and the bark provides a platform for lichens and fungi, while the fissures within it are shelter for beetles, spiders, earwigs and wood lice. Even the fallen leaf litter builds up beneath them to give ground mammals, amphibians and insects a place to forage and hibernate.

You may ask, what is the value of attracting all these insects to your garden? The truth is that less than 1 per cent of our insects are considered garden pests, and their presence becomes a food source for the predators further up the chain. The development of a healthy food chain means that soon the use of harmful, indiscriminate, chemical pest control will be negated. As top predators are encouraged by a plentiful food supply, you may be rewarded by the sight of visiting owls hunting for voles and mice, while ground beetles, thrushes and hedgehogs will take care of your unwanted slugs, and a family of Blue Tits will devour over 100,000 aphids in a season!

However, some species of tree provide more support to wildlife than others, so if you only have room for one tree, give a second thought to selecting a species that is particularly wildlife friendly. Our native trees tend to score very highly on this front, but not many of us will be able to accommodate a fully grown English oak, ash or beech in all its majestic glory.

However, there is a way round this problem and that is to plant a line of mixed hedging along your boundary. Many of our native woodland trees cope very well when planted as a hedge. Again, autumn is the best time to plant bare root, one-year-old whips. Although they may appear small and insignificant when they arrive, each should cost less than £1.00 and will establish quickly, so that within five years you will be the proud owner of a thick healthy hedge and a ready made haven for wildlife.

Hedging

Here are some examples of wildlife friendly species that can be planted as hedging:

Ilex aquifolium (Holly, can grow more than 8m) This is an evergreen tree, providing year-round shelter for roosting birds. The female plant has winter berries that are food for garden birds such as Blackbirds and Robins. Its insignificant spring flowers attract the Holly Blue butterfly whose caterpillars feed on the buds and leaves.

Frangula alnus/Rhamnus cathartica (Buckthorn) The small yellow flowers of these trees attract the early bumblebees and newly emerging Brimstone and Green Hairstreak butterflies who also lay their eggs on the leaves. Black berries are borne on the female plants in autumn which become food for hungry birds and mammals.

Rhamnus cathartica (Buckthorn) with berries

Corylus avellana (Hazel, can grow up to 12m but it can be coppiced or grown as a hedge) It is the primary home for the endangered dormouse which eats the caterpillars, such as the Large Emerald, Small White Wave, Barred Umber and Nut Tree Tussock moths, that live on the leaves in the summer and the cob nuts in autumn. Amongst many others, Woodpeckers, Nuthatches, Jays, mice and squirrels all feast on this plant. Hazel catkins provide early pollen for bees, and the bark is often covered in moss or lichen on older trees.

Corylus avellana (Hazel)

Prunus spinosa (Blackthorn) This is a common hedgerow species, recognisable in autumn by the presence of sloes. The berries are a valuable food source for birds and small mammals, while it is also home to the caterpillars of the Magpie, Lackey and Common Emerald moths and the Brown Hairstreak butterfly.

Prunus spinosa (Blackthorn) in blossom

Quercus robur (English oak, can grow up to 25m) It has been said to support up to an incredible 532 species of living things. The acorns attract birds, mice and other mammals. The leaves are food for many types of caterpillar including the Purple Hairstreak butterfly. If you stand under an oak tree in summer and just listen, you will hear the humming of tree bees, wasps and all sorts of other insects living in the canopy above.

Salix caprea (Goat willow/pussy willow, can grow more than 8m) The long tubular catkins are amongst the first trees to flower after winter and so are an invaluable source of early nectar to emerging bumblebees and miner bees. The moth caterpillars of Sallow Kitten, Sallow Clearwing, Dusky Clearwing and Lunar Hornet all live on these leaves. Willow trees are thought to support over 300 species of insects, birds and invertebrates.

Salix caprea (Goat willow/pussy willow)

Crataegus monogyna (Hawthorn, can grow up to 5m) Its scented white/pink blossom signifies the start of spring; its leaves are the larval food for many moths. Its autumn haws are a valuable food for migratory birds such as Redwing and it is said to support 149 associated insects.

Crataegus monogyna (Hawthorn) in blossom

 

Crataegus monogyna (Hawthorn) haws

Euonymus europaeus (Spindle) This is a native shrubby tree that grows up to 4 m. It has excellent autumn colour, particularly the cultivar ‘Red Cascade’ which has orange berries bursting out of bright pink cases. They attract Robins and Song Thrushes.

Euonymus europaeus (Spindle) berries

Elder, yew, field maple, wild plum, dogwood and beech are also fabulous species for nature, offering, between them, shelter, berries and flowers. Add them into the hedgerow too with some flowering shrubs like Rosa rugosa, ivy, honeysuckle and the native clematis (old man’s beard) to scramble over.

Specimen trees

If you have a small garden and want a specimen tree rather than a hedge, then choose a tree that either has an upright, columnar habit or one with an airy branch network so it won’t cast too much shade. Grow a small-headed tree in a pot or plant out one that won’t reach more than about 4m. Perhaps try a species like Malus (apple), Prunus (cherry), Fagus (beech) or Carpinus betulus (hornbeam) – the latter two keep their leaves over winter – which can all be trained as a fan, cordon or espalier, grown two-dimensionally against a boundary wall or fence. Alternatively, fruit trees grafted onto dwarfing rootstock can make a wonderful focal point. Look for a species that offers as much seasonal interest as possible, especially if space is at a premium. Your tree needs to earn it’s keep. Look for a tree that can give you scented flowers, berries or fruit and interest in its bark or foliage with unusual shaped leaves or autumn colour.

For example, here are some suggestions of wildlife friendly trees with prolonged seasonal interest:

Sorbus aucuparia (Mountain Ash) Can grow more than 15m high, but its soft, airy foliage and thin, columnar habit means it may still be suitable for a small garden. It is a delicate looking tree with clusters of autumn berries for birds like Redstart and Redwing and it is the food plant of the Buff Tip moth amongst others.

Sorbus aucuparia (Mountain Ash) in flower

Sorbus aucuparia (Mountain Ash) with berries

Malus domestica (Apple) There are literally hundreds of varieties of apple to chose from but if you have a small garden, chose a dwarf rootstock such as that grown on M27, M26 or M9.  Make sure you buy a self-fertile variety if there isn’t a companion pollinator tree nearby. The trees have beautiful spring blossom and the autumn fruit can be picked, eaten, stored or juiced by us, while windfalls present a bonanza to ground mammals which are quick to scavenge fallen fruit but any left to rot on the ground will be enjoyed by Red Admiral and Comma butterflies basking in the sun as they feed on the juices.  

Malus domestica (Apple) 

Malus sylvestris (Crab apple) Again, so many beautiful cultivars to choose from. ‘Red Sentinel’ sometimes hangs onto its fruit all winter so is a superb option for added visual interest as well as a prolonged food supply for the birds. Crab apples are a manageable size, up to 5m, but can also be strictly trained as espaliers and they come in weeping forms too. They have gorgeous spring blossom and are excellent pollinators for other fruit trees. Their beautiful blossom is popular with so many insects. The emerging spring foliage is so pretty, with winning combinations of deep purple leaves against pink blossom or white blossom emerging from scarlet buds over fresh lime green leaves. The autumn fruits themselves come in a range of colours from the yellow of M.‘Golden Hornet’ to the multi-tone fruit of M.‘Evereste’ in orange, yellow and red. The giant red fruits of M.‘John Downie’ make the most fabulous looking crab apple jelly. Crab apple trees attract birds like Fieldfare, Song Thrush and Blackbirds.

Although our native species are perhaps the most beneficial to wildlife, their large size and sometimes lack of visual appeal may go against them as you make your choice. However, you may be able to find smaller cultivars or cultivars with slightly more aesthetic appeal. For example, Betula pendula (Silver Birch) can reach 15–20m but has many smaller growing cultivars such as Betula utilis var. jacquemontii which has particularly white bark, golden autumn tints and can still support hundreds of species of insect and birds. Birds such as finches, tits and Siskin flock to the tree not only to feed on its abundant seeds but also for the insects it hosts. Multi-stemmed forms can be stunning specimen trees that can be under-planted as a focal point for the garden. 

Betula pendula (Silver Birch) 

The native goat willow, Salix caprea, grows to over 12m in height but there is a much smaller cultivar, Salix caprea ‘Kilmarnock‘ along with Salix alba var. vitellina ‘Britzensis’ that can be pollarded and its new shoots have the brightest coloured stems in winter. They can both be under-planted with summer bedding plants in a front garden as they do not cast too much shade. 

The native Sorbus aucuparia has a smaller growing cultivar, S. ‘Sheerwater Seedling’. This form still flowers in spring and provides heavy clusters of red berries in the autumn. However, the gorgeous autumnal tints of this variety are stunning as the leaves change to a fiery red.  

It seems almost impossible to chose just one tree, but try asking yourself this: what insect/animal/bird do I want to see in my garden? Work backwards with your boundaries, aspect and soil conditions, and plant the tree that will encourage them and flourish in its location. Give it time and they will come.

For North Curry Wildlife Group's website, please see: https://www.northcurrywildlife.com/