The colour comes from catkins, the male flowers of the hazel, which hang fluffy and limp like the lambs tails by which they are also known. Bees mooch around the branches, slowed by the cold air but collecting precious pollen from the amber spirals.

The hazel doesn’t rely upon the bees for pollination and instead lets the wind scatter its pollen across the small, red-tufted female flowers that are tucked up tight against the twigs and branches. When the sun shines on a breezy winter day, yellow clouds of pollen may billow above a hazel copse.

The flowers, once fertilised, will begin the gradual transformation into the nuts with which we are so familiar. Back in the autumn, woodpeckers hammered into the brown shells while dormice nibbled neat holes before gorging themselves ready for hibernation. Other mammals such as squirrels, mice and voles will have cached hazelnuts in log piles or beneath the ground and those that aren’t recovered may germinate to one day form catkins of their own.

Left alone, the hazel may survive for a relatively short 80 years, but coppicing encourages growth for many hundreds more. Upon reaching a diameter of around 7.5cm (3 in), the first trunk is cut back to the stool. Multiple stems then grow that will be coppiced again every 6 to 10 years. These growths are long, straight and incredibly flexible, perfect for the construction of hurdle fencing and useful too for lightweight walking sticks, beanpoles and even rod rests for fishermen.

Where to see: scrub and hedgerows

Hazelnut

Borne in clusters, hazelnuts have edible kernels inside hard-shells that are prized by hedgerow foragers (although small mammels often reach them first). Wood mice nibble a circular hole in the nut, squirrels split it neatly in half vertically, bank voles gnaw off the pointed end.

Common Alder, Alnus glutinosa

The alder is not a large tree, nor does it live for particularly long, but it has a fondness for water that few other trees can match. In low quality soil, the alder is a pioneer. Within its root nodules live bacteria, Frankia alni, that feed on sugars produced by the tree. The Frankia begin processes that allow the alder to pass amino acids and nitrogen into the soil, improving fertility for future growth.

On a steep riverbank, the alder sends out roots from its lower trunk that reach sideways to find footing, preventing the tree from being unseated from below. Those roots that finger out over the water will tuck back beneath themselves, forming a tangle that provides sanctuary for fish and invertebrates. Should a limb fall into the water, then it will not necessarily rot. If alder remains submerged, then it will solidify like granite. Man has long utilised this property, building crannogs upon alder in the lochs and loughs of Scotland and Ireland, and using it as a foundation in Amsterdam and Venice.

In March, the catkins of the alder are maturing from claret to yellow and, once pollinated, the smaller female flowers harden like miniature pine cones. They remain on the tree until long after the rounded leaves have fallen, and snare the lines of anglers who cast for the fish that lurk in the root mass beneath.

Where to see: along river banks, fields, near water

Alder seeds

Alder’s small winged seeds, which ripen inside black globular cones, are important food for small finches in autumn. Alder is a riverside tree, so vast quantities of buoyant seed are carried by floodwater and washed ashore on muddy banks that provide the moist conditions needed for germination.

More related content:

• Famous trees of the UK
• F is for Forest Bathing: mindfulness in nature
• Britain’s best forests and woodlands

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Hawthorn, Crataegus monogyna

Though a single tree may grow to 12m (40ft), hawthorn is most often found tightly packed in our hedgerows. Its dense, fast-growing branches have long been recognised as a perfect natural barrier, and some 200,000 miles of hawthorn hedges are estimated to have been planted during the 18th and 19th centuries.

It says much of our changing seasons that we should consider the hawthorn in April, when the blossom dotting our hedgerows has long been associated with May.

As our winters shorten, so the white flowers of the hawthorn dazzle ever earlier each spring, and though we still refer to May blossom, in some parts of the country, the petals are no more than a browning carpet when the month itself finally arrives.

In spring the hawthorn is prime avian real estate. The twists of fissured bark and stiffened, unyielding thorns create perfect nesting habitat for small birds, safe from the beaks of corvids and too tight for a female cuckoo to sneak in and lay her deceit. A weasel or adder might be lithe enough to snake through the tangled mass, but larger mammals, such as foxes, martens and pet cats can do nothing but wait until the young birds fledge.

Almost as soon as they unfurl, the deep-lobed shiny, green leaves will be alive with caterpillars – many moth species are almost wholly dependant upon the hawthorn. The flowers provide pollen for insects such as bees, but also dormice who will not long have risen from hibernation.

Where to see: commonly found in hedgerows, woodland and scrub.

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Silver Birch, Betula pendula

The silver and downy birch, which are both widespread, are well regarded by mycologists – especially those looking for an edible treat. The acidic soil in which they thrive provides good ground for some of our most iconic mushrooms. Ceps, orange birch boletes, chanterelles and fly agaric all flourish beneath the birch, especially when the tree is a dominant species within a mixed woodland.

As the leaves begin to brown and fall, finches fill the branches to feed upon the tiny winged seeds. There is little commercial value in the wood, but this is a tree long associated with fertility. In the Highlands, it was once believed that an unbearing cow could be made fecund if she was herded with a branch of birch.

Betula pendula In his 1802 Romantic work The Picture; or The Lover’s Resolution, Samuel Taylor Coleridge finds himself beneath a “weeping birch”.

He calls it the “Most beautiful of forest trees – the Lady of the woods”. It is hard to disagree. There is a fragility to a birch tree. Not just in the flaking bark that cracks and peels like varnish on the weathered hull of a boat, but also the delicate branches that tremble in the softest of breezes.

On a dank winter day, the trunks shimmer through the mist like the stretched ghosts of old foresters. And even in summer, with the tree in full leaf, the trunk remains distinct. The leaves of a birch are small but vibrant, bright green emeralds glistening against grey. They still hold their colour in August, and remain sparse, allowing plenty of light to reach the forest floor. Here, smaller plants can find room for their own growth, though in late summer it is fungi with which the birch is often associated.

Where to see: Mixed woodlands

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Elder, Sambucus nigra

In June, the elder is at its finest, its leaves almost lost beneath the white of its flowers. The petals are small and clustered, but form an umbel that is broad and soporifically scented, like a dollop of perfume-infused, inflorescent ice-cream. The crowns of elderflower have long been gathered. Some are dunked in batter and fried, while others find their way into cordials, wines or bottles of fermented fizz. This impacts little upon the tree’s regeneration, however, and by August those pollinated flowers that remain will have transformed into berries that ripen from green to deep claret.

These too may be harvested, by makers of wine or roach anglers sourcing a free bait. Many more are eaten by birds, with blackcaps, thrushes and woodpigeons all content to gorge before dispersing the undigested seeds through their droppings.

It was once believed that the elder tree had the power to render useless the evil spells of a witch. As a result, trees would be planted at gateways and in gardens, with whole hedgerows encircling the homes of the most superstitious.

It was also believed that breaking so much as a twig of elder might bring ill fortune, though such a portent is overlooked by anyone searching for kindling. The dry, brittle branches of an elder burn with great speed and heat.

Where to see: woodlands, parks and gardens

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Oak, Quercus robur

Explore local parks and woodlands and keep an eye out for the Oak tree, also known as Quercus robur. Despite the fact that it may stand for a millennium, the oak is a surprisingly fast-growing tree. From a sapling, it may spend 100 years reaching impatiently for the sky, before easing into maturity and spreading itself outwards rather than up.  The bark is rich in tannin and as it grows old so it hardens like crocodile skin, armouring a trunk that may be three metres across.

As September approaches, the purple hairstreak butterflies dance their last in the canopy, having deposited their eggs at the bases of the leaf-buds. In spring, the newly hatched caterpillars are sought by many birds, not least the pied flycatcher – a species that favours the oak above any other tree.

The acorns are just beginning to brown, but won’t fall until later in autumn when squirrels will be busy on the forest floor – collecting and caching alongside the electric blue flash of the jay, who will bury acorns by the hundred in order to dig them out when winter bites.

The leaves have distinctive rounded lobes and, though small, are robust and feel almost as if formed from fabric. They carry their deep green late into the year and often share the branches with apple-shaped galls of the wasp species Biorhiza pallida.

Oakwood has long been used in the construction of houses and boats, and by furniture makers and coopers. It has great strength, and man has long revered its majesty. This is a tree heralded throughout history; in Greek mythology the oak was regarded as a tree sacred to Zeus, while the ancient Germanic peoples believed that their gods lived within the branches themselves.

Where to see: parks and woodland

Learn more in our oak tree guide

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Common lime, Tilia x europea

Amid the rich potpourri of high summer, the scent of the lime wafts as unexpectedly as it is deliciously sweet. Discover more about the common lime, also known as tilia x europea.Unlike the pink and white blossoms of early spring or the creamy wallop of elderflower in June, the petals of lime are somewhat more unassuming. Though tinged with yellow, they hide themselves beneath the flat, heart-shaped leaves and all but vanish into green.

Bees find the flowers irresistible, and the buzz of insects is almost as intense as the fragrance. Lime-tree or Linden honey is highly regarded for its sweet and mildly astringent taste, with one single tree able to produce 40 pounds (18kg) given favourable conditions.

Feeding on the leaves is a myriad of moth caterpillars, among them the lime hawk, vapourer and peppered. It is the common lime that we see in our parks and avenues, a hybrid of the scarcer but native small-leaved and large-leaved trees. Its shade, smell and solidity has long made the common lime popular as an ornamental plant.

A tree might live for five centuries, and they are often grown for commercial use. In North America and China, the timber of the Tilia genus is known as basswood, and is widely used in the manufacture of furniture and window dressings. The trunks grow straight and tall, providing a softwood that is easily formed, yet strong and straight-grained.

In Europe, the lime has long been associated with fertility, and was often planted in France after battles as a symbol of liberty.

Where to see: commonly found in parks and along residential streets.

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