Hedge and tree

Poster for the hedge and tree habitat (Living Field)
Poster for the hedge and tree habitat (Living Field)

Hedges and trees form vertical and linear features in cropland that act as windbreaks for crops and offer cover and refuge for other plants and for animals. Hedges can grow into trees and trees can be cut into hedges.  Many of the cropland’s tree-lines grew out of hedges, while trees cut 1-2 m in height can live to form durable hedges.

Like stone walls, hedges were commonly put in to reinforce legal boundaries and to confine stock.  Blackthorn, hawthorn, hazel, elder, alder, pear, apple, rose, cherry, elm, holly, beech, ash are all constituents of hedges. The number of species in a hedge sometimes increases over time as new plants find their way in; but few conifers such as pine, spruce and yew, survive in hedges. Except for holly, the species lose their leaves in autumn and are leafless through the winter.

Blackthorn flowering in the Living Field garden 17 April 2014
Blackthorn flowering in the Living Field garden 17 April 2014

Tree-lines are a defining feature of the croplands. Look at any landscape from a distance and they can be seen or their absence felt. Small woodlands and copses are also planted for shelter and firewood.  While tree lines are mostly deciduous – ash, oak, beech, and elm once – copses and farm woodlands can be conifers or mixtures of conifers and deciduous trees.  

While some hedges have been taken out to create larger fields, much of the cropland is still well populated with trees and shrubs, some quite magnificent, giving it that characteristic temperate, ‘north atlantic’ look of lush foliage and timeless stability.  

Hedge and tree - (upper) rowan berries, blackthorn flower, (middle) rose hips, autumn leaf, elder berries, (lower) hawthorn flower, dead trunk with insect nest-holes (Living Field collection)
Hedge and tree – (upper) rowan berries, blackthorn flower, (middle) rose hips, autumn leaf, elder berries, (lower) hawthorn flower, dead trunk with insect nest-holes (Living Field collection)

Yet both trees and hedges need to be managed – trees fall in the gales, or are felled for wood, and need to be replanted; and the current practice of shaving the top off hedges year after year creates a surface web of branches, hiding internal holes that lead to death and gaps. Hedges also get their unwanted share of fertiliser and pesticide from operations in the field, so have to recover from spray-burn and to compete with aggressive weeds like cleavers, nettle and thistles. The future of the cropland hedge is not assured.

Hedges were planted round the garden and a few trees were put in just north of the pond and ditch. Their influence was immediate – birds sing from the trees and feed off the hedges.

Here are some of the species.

Alder Alnus glutinous is a small tree that prefers wet soil (but where’s not wet round here in some years).  There are a couple of trees near the pond and other individuals in the hedges. It has catkins (lower left), similar to hazel, and female ‘cones’ that persist, black through the winter.

Hazel Corylus avellana also lives as  small tree with the alder, but probably takes better to hedge-life.  The long catkins appear in spring with the very small female flowers, which if you look closely, emerge red at the tip of small buds.

Blackthorn Of the three cherries still common in the croplands,  Prunus spinosa is the first one to flower, so long as branches are left to grow long, and is well represented in the Living Field hedges. It is well-named spinosa; but slightly less well known are the black or blue-black fruits, named sloes, welcomed as flavouring to certain drinks such as gin.

Elder Sambucus nigra is a fast-growing, pithy and light-stemmed, large shrub, that reaches 2-3 m in height. Its stinking foliage contrasts with frothy, cream flower heads emerging in May and June and red-blue fruits that get picked by the birds, one by one, as they ripen later in the year. The stems grow to a few inches across and usually have a hole in the middle (centre inset below). Flowers and fruits are edible.

Hawthorn Crataegus monogyna was not planted as a tree in the garden but forms a neat small tree when sheltered in the wild.  It flowers later than its relatives, the blackthorn, gean and bird cherry. It leaves before it flowers while the blackthorn flowers before it leaves – as the saying goes – not always true.

Birch, species of Betula,  here as a couple of small trees,  has a characteristic whitish, peeling bark and small, almost diamond-shaped leaves that filter rather than block the light. Leaves that develop in the shade are deeper green and larger than those  exposed to the sun and wind. More at home in the higher croplands than with the oaks and ashes of the lowlands.

Birch tree, with white trunk inset, leaf canopy from below, shade leaves and trunk with peeling bark.

Bird-cherry Prunus padus became uncommon as a self-seeded, wild plant in the croplands, but has recently been planted widely on waysides and roundabouts. In among the other cherries in the Living Field hedges, it has  bigger leaves and holds its flowers on short curving sub-branches.

Wild rose Rosa species extend their spiny outgrowths from all parts of the hedges, growing as small bushes or climbing 3 to 4 m then cascading down. Their small flowers range from pink to white and all shades between. Their bright red or brown hips extend the colouration of the garden and its autumn-menu options for inverts and birds. Rose hips have been a source of Vitamin C (rose hip syrup) and notably came to the country’s aid during scarcity. Several species grow in the hedges, some difficult to identify.

Rose growing tall in an uncut hedge and (insets) white flower and thorny stem, cluster of leaf and flower and red hips in autumn.

Holly Ilex aquilifolium is the only plant of the hedges to keep its leaves over the winter.  And by keeping its leaves, so spiny and impenetrable, it offers space for small animals that seek a refuge. Holly is one of few plants – another is the stinging nettle – that have the sexes on different individuals, yet while they are cut short, the branches rarely flower; so a few individuals were left uncut to grow into small trees, to see if some would be female and produce berries.

Rowan Sorbus aucuparia is perhaps the one small tree that – albeit with gean – best defines the croplands and the higher grazing lands. Sometimes surviving in a cut hedge, and not often comfortable below oak, ash and beech, it nevertheless stands out where it grows by form and colour and usefulness. The garden has one rowan tree but most others of the species are part of the hedges, where they flower and fruit if left uncut for a year or two.

Rowan leaves in early summer, floral bunch, fruits and leaves in autumn.

Management

Mixed-species hedges were planted round the perimeter and along the divide between west and east gardens. They are part of the hedge network that permeates the farm. All hedge and tree species are local and were sourced from local, specialist nurseries.  The plants were put in as as small ‘whips’ in 2004 and have since grown into large shrubs. They are  cut back every few years to about 1 m in height, but usually one side at a time, so that the hedge retains some long, flowering branches and adequate shelter. Most species in the hedge will grow into trees if not cut back.

A few trees – alder, birch, hazel, wild cherry – were brought in as large saplings and planted in a clump to the east of the dividing hedge just north of the pond.  Given the small area of the garden, tree species were chosen  that do not grow to a great height and girth like the oaks, ash and beech.  

Light filtered through birch leaves (Living Field collection)
Light filtered through birch leaves (Living Field collection)

Uses

[in progress]

sustainable croplands