Circular walk from Jacobstow to Poulza
  1. From the Parish Hall, turn right onto the lane and follow it downhill to a junction opposite a cottage with a wagon wheel on the wall.

    Jacobstow is thought to have arisen from a Celtic religious settlement in early mediaeval times. It's likely that it would have originally had a Cornish name, quite possibly starting with "lan" to indicate a religious enclosure.

    The Saxons had a stronghold in northeastern Cornwall, which is reflected in many of the place names (-stow, -bury, -ton, -worthy, -cott, -ham, -ford etc). As you move further west, the Celtic place names (Tre-, Pen-, Lan-) become more common.

  2. Turn right and follow the lane to a ford at the bottom of the valley.

    The river is the same one you'll cross towards the end of the walk. North of Wainhouse Corner, the valleys on this side of the A39 all feed water into a major tributary of the river at Bude, which merges with the River Strat at Helebridge. Jacobstow is in the upper reaches of this catchment area.

  3. At the ford, cross via the footbridge on the left or the path on the right to rejoin the track. Follow the track uphill until you reach a barn on your right.

    The first record of Poulza is from 1179 and the meaning of the name is not known. In 1421, a chapel dedicated to St James was recorded here. No mediaeval buildings remain but some of the farm buildings in Lower Poulza date from the 18th Century or before. By Victorian times, the settlement had been divided into Lower and Higher Poulza.

  4. Continue past the barn and follow the track around a bend to the left to reach a fork.

    Being somewhat away from civilisation, originally, post wasn't delivered to Poulza, but instead to a farm off the Headon Cross main road, consequently known as "Lower Poulza Post". Although no longer the postal hub for Lower Poulza, Lower Poulza Post carved a new niche for itself as Britain's only naturist farm campsite. Don't bother packing your binoculars - this walk doesn't pass very close.

  5. At the fork, bear left to stay on the track and keep following it until you see a waymark on the left about 50m before the track ends at a gate.

    Oak was often associated with the gods of thunder as it was often split by lightning, probably because an oak is often the tallest tree in the area. Oak was also the sacred wood burnt by the druids for their mid-summer sacrifice.

  6. Turn left at the waymark and follow the footpath into the woods, keeping right along the wall until you reach a stile.

    The woods contain plant species such as wood sorrel which are indicators that the woodland here is ancient. Mixed deciduous woodland such as this is an important habitat supporting a lot of wildlife.

    As the name suggests, Wood Sorrel grows in shady places and as it spreads slowly it is used as an indicator of ancient woodland. It is recognisable by a carpet of bright green leaves that look a bit like clover. It is said that St Patrick used the three-lobed leaves to illustrate the Holy Trinity and therefore it's one of the plants dedicated to him and collectively known as "shamrock". Around Easter, wood sorrel produces delicate white flowers which gives rise to its European common name of Alleluia.

    The leaves and flowers fold up at night and reopen each morning, and they do the same during rain. This is a protection mechanism to avoid damage to the leaves when there is no solar power available, or pollen being knocked out of the flowers by the rain.

    Ivy is rarely a threat to healthy trees. Ivy is not a parasite. Since it has its own root system, it absorbs its own nutrients. It simply uses a tree for support. The main risk to trees is during strong winds when the surface of the ivy can act as a sail which, together with the extra weight from the ivy, can cause a tree to fall.

  7. Cross the stile and continue ahead to the gates out of the pen. Go through these (by removing the metal pole in the centre if closed) then follow the right hedge to a gate in the far corner.

    If there are sheep in the field and you have a dog, make sure it's securely on its lead (sheep are prone to panic and injuring themselves even if a dog is just being inquisitive). If the sheep start bleating, this means they are scared and they are liable to panic.

    If there are pregnant sheep in the field, be particularly sensitive as a scare can cause a miscarriage. If there are sheep in the field with lambs, avoid approaching them closely, making loud noises or walking between a lamb and its mother, as you may provoke the mother to defend her young.

    Sheep may look cute but if provoked they can cause serious injury (hence the verb "to ram"). Generally, the best plan is to walk quietly along the hedges and they will move away or ignore you.

  8. Go through the gate and turn left onto a track. Follow the track until it emerges onto a lane.

    In June, there are foxgloves along the track and lane which attract bumblebees.

    Foxgloves are reliant on bumblebees for pollination and bumblebees are much more active when the weather is good. Partly, as an insurance policy against bad weather, foxgloves have evolved to stagger their flowering over several weeks, starting with the flowers at the base of the stalk and working up to the top, where the higher flowers protrude over other vegetation that has grown up in that time.

    In situations where ducks need to watch out for predators, they can sleep one half of their brain at a time, keeping one eye open for danger. In safer circumstances, ducks will sleep fully.

  9. Continue ahead to join the lane and follow it, passing South Dinnicombe farm, until it ends at a T-junction opposite "Little Dinnicombe".

    The pheasant is named after the Ancient town of Phasis (now in West Georgia) and the birds were naturalised in the UK by the 10th Century with introductions both from the Romano-British and the Normans. However, by the 17th Century they had become extinct in most of the British Isles.

    In the 1830s, the pheasant was rediscovered as a game bird and since then it has been reared extensively for shooting. The pheasant has a life expectancy of less than a year in the wild and it is only common because around 30 million pheasants are released each year on shooting estates.

  10. At the T-junction, turn left and follow the lane back towards Jacobstow until it also ends at a T-junction.

    At the bottom of the valley, the lane crosses a stream, alongside which, wild garlic grows.

    Despite the pungent smell, the leaves of wild garlic are quite delicate in flavour so can be used quite large quantities in cooking or more sparingly within salads. They are at their most fiery early in the season. As well as a garlic flavour, the leaves have a slight (though not excessive) bitter note which can be balanced against sweet flavours (e.g. tomato or roasted pepper) or salty flavours like bacon to cut through a rich sauce.

    As well as forgetting where they buried some of them, squirrels may also lose a quarter of their buried food to birds, other rodents and fellow squirrels. Squirrels therefore use dummy tactics to confuse thieves by sometimes just pretending to bury a nut.

  11. Turn left at the junction, signposted to Jacobstow, and follow the lane to the church.

    The stream just before you reach the church starts from a spring near the A39 which rises through a holy well which is dedicated to St James. It is thought that its proximity to the A39 (which was already a main road in mediaeval times) caused it to be adopted by passing pilgrims as a shrine to St James of Compostela in Northern Spain. This is likely to have resulted in the dedication of the church and the Saxon name for the settlement.

  12. From Jacobstow church, follow the lane uphill to return to the Parish Hall.

    Jacobstow parish church is dedicated to St James and there is evidence of a former Saxon church on the same site. An ancient altar stone is in the south aisle chapel: it was the main altar stone up to about 1550, in the reign of Edward VI. At this time, the Church of England was becoming more Protestant and an Act required that all altar stones should be removed. This one became a footbridge over a stream. It was found and moved back to the churchyard as a seat in the 1800s, and installed in the south aisle chapel in 1972.

During Saxon times, the River Tamar was used as the border between Devon and Cornwall. After the Norman Conquest, a new border was drawn up between the two counties using the River Ottery as the dividing line near Launceston. The result was that the parishes of North Petherwin and Werrington were lost into Devon and remained there for nearly 900 years until 1966 when the border was altered to once again be along the River Tamar.

Mosses are close relatives of the first plants to colonise the land 500 million years ago. They descended originally from freshwater algae but evolved an outer coating that protected them from the temperature changes and UV radiation that made life on the land more of a challenge than in the water. There are now estimated to be over 10,000 species of moss.

Mosses reproduce with tiny spores rather than seeds. Many mosses use wind to carry their spores and produce tiny stalks with the spore-releasing equipment on the top in order to catch the wind - these can be seen as thread-like structures standing up from the moss. These spore-releasing devices often have a ring of teeth around the edge (visible with a magnifying glass) to control the release of the spores, allowing them to be released gradually over a period of time to catch gusts of wind of different speeds and in different directions.

Sphagnum (peat) mosses use compressed air to launch their spores. To get an idea of the acceleration that the spores are launched with, an astronaut in a rocket launch experiences an acceleration g-force of about 3 g and the maximum in a fighter jet is about 9 g. Sphagnum moss spores are accelerated at 36,000 g!

Mosses don't have roots but instead have little rootlets known as rhizoids. Since there is no need to root into soil, mosses can grow on stones, tree trunks, buildings etc. This together with their wind-carried spores makes them excellent colonisers of barren land. The buildup of organic material from dead moss then provides an environment that other small plants can start to colonise.

Mosses' lack of deep roots mean they need to store their own supply of water during dry periods which is why they are found in shady places that are not dried-out by the sun. This also applies to moss on trees - it rarely grows on the south-facing part of the trunk which can be used as a crude form of compass when navigating.

Some mosses are able to absorb 20-30 times their own weight in liquid. Moss was used in several ancient cultures as nappies: babies were carried in a moss-lined bag to prevent leaks. Moss has also traditionally been used to line hanging baskets which are very prone to drying-out. Areas of moss help to protect soil from erosion by runoff and rivers from sediment and flooding by capturing rainfall and giving it chance to soak slowly into the soil.

Ferns evolved a long time before flowering plants and dominated the planet during the Carboniferous period. The bark from tree ferns during this period is thought to have been the main source of the planet's coal reserves.

Fern fronds form in a coil (known as a crozier or fiddlehead) with the delicate tip protected in the centre. As the outer parts begin to photosynthesise, the sugars they produce cause more water to be drawn into the leaf, causing it to expand and gradually unfurl.

Ferns produce 2 different types of leaf (although they often look quite similar). The normal leaves are used for photosynthesis of sugars just like in other plants. Ferns also produce a special kind of spore-bearing leaf which can often be identified from the dots on the underside. In hart's tongue ferns, these are really obvious.

Ferns produce neither flowers nor seeds and rely on the tiny spores for their reproduction which are most commonly distributed by the wind. This allows them to colonise some quite random places such as rocky ledges that heavier seeds might not reach. Since the spores come from just one parent fern, the offspring is a genetic clone.

The spore from a fern doesn't grow into a fern. Instead it grows into an organism resembling a liverwort (i.e. a small green blob). Instead of producing spores, these produce eggs and also sperm which they interchange with neighbouring blobs to get a new mix of genes. The fertilised egg grows into a new fern and so this alternating process of ferns and blobs repeats.

The bramble is a member of the rose family and there are over 320 species of bramble in the UK. This is a big part of why not all blackberries ripen at the same time, and vary in size and flavour.

The word "bramble" comes from bræmaz - a word of Germanic origin meaning "prickly". The study of brambles is involved enough to be considered a discipline of its own and is known as batology (from baton - the Ancient Greek word for blackberry).

Bramble roots are perennial but its shoots last just two years. In the first year, the shoots grow vigorously (up to 8cm in one day!). In the second year, the shoots mature and send out side-shoots with flowers.

The growth rhythm of brambles is so steady that it can be used in forensics to work out how long remains have been at a crime scene.

Bramble flowers produce a lot of nectar so they attract bees and butterflies which spread the pollen between plants. One study found the bramble flowers as the fifth highest nectar producers out of the 175 species studied. Brimstone and Speckled Wood butterflies are particularly fond of bramble flowers.

As well as through pollen being transferred by insects from other plants, if there are not many insects around (e.g. in cold or wet weather), bramble flowers are able to produce seeds without being fertilised (the flower is able to use its own pollen).

Bramble seeds are spread very widely by being attached to a tasty blackberry. Mammals, birds, insects and even some fish will eat blackberries. Bramble seeds can survive up to 100 years in the soil, which helps them to colonise recently-cleared land.

As well as producing seeds both sexually and asexually, brambles can also clone themselves to create daughter plants either via underground stems (rhizomes) or by the over-ground stems rooting where they meet the ground.

Due to their rapid growth, brambles are often one of the first plants to colonise brown-field sites but, unlike heather, brambles are not particularly tolerant of metal-contaminated soil. Heavy metals interfere with plant metabolisms (e.g. the magnesium in chlorophyll could get replaced by another metal instead) and this is noticeable as leaf discolorations such as paler green areas or red edges.

Researchers have worked out that they can do image processing on the colours of bramble leaves from aerial images to measure the level of contamination and even the type of contamination by creating "fingerprints" of leaf colours associated with a particular metal. This seems to work fairly well with completely bare areas (likely to have metal levels so high that brambles can't actually grow) showing up immediately adjacent to those calculated as the most polluted bramble-covered areas.

Robins are able to hover like kingfishers and hummingbirds and use this skill when feeding from bird feeders, which they are unable to cling to.

Robins are also able to see magnetic fields. Receptors in their eyes make magnetic fields appear as patterns of light or colour which allows them to use the Earth's magnetic field for navigation. They only seem to use their right eye for this as the left half of their brain (linked to the right eye) does the processing.

Unlike many birds that just sing in spring, robins sing nearly all year round. In fact during winter if you hear birdsong, it's most likely to be a robin. Despite how cute robins look, they are actually very territorial and the chirp is an aggressive warning to any would-be intruders not to even think of trying it. When robins don't sing, this a sign that their body fat reserves are low and they are conserving what little they have left until food becomes more plentiful.

The tradition of robins on Christmas cards is thought to arise from Victorian postmen wearing red jackets. Consequently they were nicknamed Robins.

The Cornish name for the bird is rudhek from rudh = "red" (in Cornish, "dh" is pronounced like the "th" in "with"). Cornish place names like Bedruthan, Ruthern and Redruth are all based on the colour red.

The blackbird is a species of thrush. The name "blackbird" is mediaeval, first recorded in 1486. Since most of the crow family is also black, plus many seabirds, the choice of this particular species for the name is thought to be due to its size. Up to the 18th Century, larger birds such as crows were referred to as "fowl" and the term "bird" was only used for smaller species.

The Old English name for the blackbird was osle and up to the 17th Century this survived as in alternative names for the blackbird ranging from ouzel to woosel. One of these is used in A Midsummer Night's Dream by Shakespeare: "The Woosell cocke, so blacke of hew, With Orenge-tawny bill".

Only male blackbirds are actually black. The females are brown. The difference in appearance between males and females is known as sexual dimorphism and is an evolutionary strategy by the males to get noticed more by females at the cost of decreased chances of survival.

Blackbirds can be found in deciduous woodland, particularly where there is dense undergrowth. In the man-made landscape, hedges provide plenty of dense undergrowth and have consequently become a really important habitat for blackbirds. Moreover, many gardens have such a high density of hedges and bushes that they are able to support ten times the blackbird population versus an equivalent area of their natural woodland habitat.

Blackbirds are one of the most common birds in the UK with a population of somewhere between 10 and 15 million. However, blackbirds were in steady decline from the 1970s through to the mid-1990s. The population has only relatively recently recovered.

Blackbirds begin singing from around the end of January but it is normally the overkeen young males initially - the older, wiser males wait until March, pacing themselves for the singing period which continues into the early summer. Blackbirds have been shown to sing more during and after rain but exactly why is not yet known.

Baby blackbirds usually leave the nest before they can actually fly then hop and scramble through the bushes. Their parents watch over them so don't attempt to rescue them.

Blackbirds in the UK are resident all year round but the blackbirds that live further north (e.g. in Norway) migrate south for the winter. To help with migration and also to avoid being eaten by predators, blackbirds can sleep half their brain at a time. This allows them to get some rest whilst still maintaining enough alertness to fly or spot predators.

The reference in the nursery rhyme "sing a song a sixpence" to "four and twenty blackbirds baked in a pie" is thought to be to the 16th Century amusement (though not for the blackbirds) of producing a large pie which included an empty chamber. After the pie had been baked and was ready to be served, a trapdoor would be cut in the empty chamber and live birds were placed inside which would fly out when the pie was cut open. Live frogs were sometimes used as an alternative.

In the Christmas carol "The Twelve Days of Christmas", the line "four colly birds" is thought to be from 18th Century slang meaning "black as coal" and was a popular nickname for the blackbird. Whilst many people today sing and write "four calling birds", this is thought to be a modern misunderstanding of what was originally written.

Blackthorn is a spiny type of plum which is more broadly a member of the rose family. It is native to the UK and common on old farmland where blackthorn trees were planted as hedges to keep out cattle. It is still common in Cornish hedgerows today and also common on the coast as it's tolerant to salt.

Given the right conditions, a blackthorn tree can live 100 years and grow to about 20ft in height. In harsher environments such as by the coast the bushes may be as little as 2ft tall.

The name "blackthorn" is just a general reference to the dark colour of the bark, rather than anything specific to do with the thorns which are not any darker than the rest of the wood. It's primarily a comparison with hawthorn where the bark is lighter (in fact hawthorn is also known as "white thorn" despite not having white thorns). Just to confuse things further, the flowers of blackthorn are whiter than hawthorn!

In mediaeval times, blackthorn was associated with evil. This may also tie in with the English word "strife" which has Celtic origins. Straif was the name of a letter used in Celtic Ogham script and was originally the word for "sulphur". Some of the other letters in the script corresponded to tree names. In late mediaeval times, a retrospective assignment of trees to the letters in the alphabet used for Ogham that weren't already tree names became popular (sometimes known as the "tree alphabet") and blackthorn was chosen for Straif.

The expression "Blackthorn Winter" is a rural expression for a final cold snap in late March or early April when the blackthorn is in flower. It was generally used in the context of not getting too carried away (e.g. planting crops) if there was a warm week in early March as more frosts may still be yet to come.

Blackthorn wood is very tough and hard-wearing. In order to form its thorns, the tree allows the tips of the tiny stems that make up the thorns to die. The dead wood in the thorn tip is harder and therefore sharper than the living wood.

Blackthorn stems are often covered in fungi or bacteria and if a thorn punctures skin, these can sometimes cause infection. Any splinters left in the skin can also disintegrate over time and result in an immune response. If a puncture wound becomes infected, it's a good idea to get it checked-out in a minor injuries unit in case antibacterial or anti-fungal treatment is needed to prevent it escalating.

Due to blackthorn wood's toughness, it was used to make tool handles, walking sticks and as a traditional Celtic weapon for clubbing people to death! It is still regarded as the ultimate wood for making walking sticks. Once cut and trimmed, the wood needs to be dried for at least a year (often several) which allows moisture to escape and the wood to shrink and harden.

A cordial can be made from blackthorn blossom by dissolving 100g of sugar in 1 litre of warm water mixing one large handful of blossom, scaled up to produce the quantity you require.

The word crow is from the Old English crawe. Since this sounds a lot like the noise the bird makes, there is a misconception that the Old English is directly derived from this. In fact the word is far older. It's related the the Old Saxon kraia and can be traced back further to a Proto-Indo-European word from the late Neolithic period which is thought to mean "to call hoarsely".

The word "crow" is sometimes used to refer to the whole crow family (including jackdaws, rooks and ravens) and sometimes specifically to the common (carrion) crow. Carrion crows can be distinguished from their cousins by being totally black (jackdaws have grey heads, rooks have pale beaks) and having a slender and fairly straight beak (i.e. not the broad beak with a hooked top that a raven has). Biologists use the word "corvids" for "crow family" to avoid ambiguity, or to show off.

The collective noun for a group of crows is a "murder". The term has been traced back to around the 15th Century, originally as a murthre (which was a Middle English word that meant "murder"). It is thought that the expression may be based on crows scavenging carcasses.

Birds of the crow family are considered to be among the world's most intelligent animals, displaying a high learning ability and are able to use logic for solving problems. Researchers have found some crow species capable of not only tool use but also tool construction. Crows have also demonstrated the ability to distinguish individual humans apart by recognising facial features. If a crow encounters a cruel human, it can also teach other crows how to identify that individual.

Research has shown that crows have a much higher density of neurons in their forebrains than primates do (the density of neurons in this region is thought to correlate with intelligence).

The brain of a crow accounts for 2.7 percent of the bird's overall weight whereas an adult human's brain represents 1.9 percent of their body weight. This is even more impressive when considered in context: birds need to be as light as possible in order to fly.

Ravens are considered the most intelligent crow species, outperforming chimpanzees in some tests. Consequently an academic is quoted as saying that crows are "smarter than many undergraduates, but probably not as smart as ravens."

Studies have shown that crows are capable of self-discipline. If offered one piece of food now or two later, the crows will resist temptation and wait. However if the initial piece of food is a high value item such as sausage, they won't take the risk.

Crows are omnivores and their ability to eat anything from animal feed to potato chips has allowed them to capitalise on food sources created by humans. Their problem-solving skills also allow them to access food that less savvy animals cannot, for example tugging on bin liners and tucking each fold under their feet to raise the contents of waste bins in motorway service stations.

Crows have a vocabulary of different calls with specific meanings and these can be varied to convey emotion like a human tone of voice.

The sounds that crows make have also been found to vary with location rather like regional accents in humans. When a crow moves into a new area, it mimics the calls of the most dominant flock members to fit in with its peer group.

There is a somewhat brutal rural tradition of hanging dead crows in fields with crops. Scientists now understand why this was so effective. Research has shown that crows understand the concept of death and can distinguish an (obviously) dead crow from a taxidermically-stuffed (alive-looking) crow. Crows often gather around a dead individual in "crow funerals" to try to determine the cause of death and assess the threat to themselves. They become wary of the place a dead crow is found but will also harass humans who handle crow corpses.

In the 3rd Century BC, the Romans named their ill-fated gangplank for boarding other ships "corvus" (Latin for crow) because its end contained a large metal spike which was thought to resemble a crow's beak. The end of the gangplank was dropped from a height onto the captured ship and the spike acted as a nail, attaching the gangplank to the deck of the ship being boarded. The design was short-lived because the 36ft gangplank sticking up from the front mast of the ship did nothing for its stability and consequently resulted in almost two entire fleets being lost in rough seas.

Alexanders are a member of the carrot family and grow along roadsides in places similar to cow parsley. The leaves are more solid than the lacy cow parsley leaves and the flowers are yellow rather than white. The name arises because the plant was introduced to the UK by the Romans and was known as the "pot herb of Alexandria". It is also sometimes known as horse parsley.

Alexanders are very salt tolerant so they thrive in Cornwall's salty climate. They are just as likely to be found along coastal footpaths as along country lanes. New growth appears in the autumn so during the winter, when most other plants are dormant, it is a dominant source of greenery along paths and lanes in exposed coastal areas.

Another place that alexanders are commonly found is near the sites of mediaeval settlements, in particular religious settlements where they were cultivated by monks as a vegetable. In mediaeval cuisine they were used as an alternative to celery (which was a more bitter plant back then). It was traditionally one of the "pot herbs" that were added to stews and the dried seeds can also be used as a spice. Alexanders were particularly useful during lean winters as its new growth is available in the late Autumn, before many other spring greens.

All parts of the alexanders plant can be eaten and it is a good source of iron and vitamins A and C. The flavour has been described as somewhere between parsley and angelica. However, foraging alexanders is not recommended unless you are experienced at identifying it because novices can confuse it with hemlock (the most poisonous plant in the UK - just a few leaves from this can kill you).

The buzzard family is quite closely related to hawks and consists of a number of different species which occupy different habitat niches (e.g. colder countries further north). The buzzard species we see in the UK is the common buzzard. This is one of the largest birds of prey in Britain with a wingspan of over 4 feet.

The name buzzard is from mediaeval English buisart which itself came from the Old French word buson. It is based on the Latin word for hawk or falcon buteo hence its scientific name is Buteo buteo.

Buzzards are not quiet birds! Their long, loud "pieeuuu" call can be often be the first thing to give away their presence and is one of the easiest bird calls to remember. It is thought that the original Latin word for buzzard was probably an onomatopoeia (i.e. an imitation of the bird's call) within the constraints of what was deemed an acceptable Latin word (suggesting "pieeuuu" would probably have resulted in being fed to the lions!).

Buzzards were once thought to be a threat to game birds and were actively shot. During the 1950s-60s, the combination of myxomatosis nearly wiping out one of their main food sources and use of pesticides such as DDT caused further decline in the buzzard population. Since then the population has gradually recovered and buzzards are now the commonest and most widespread bird of prey in the UK.

A large proportion of buzzards diet is earthworms and carrion and consequently they have a reputation for being lazy and scavengers. However, when they need to be, buzzards are formidable predators. Diving on rabbits and small mammals from a slow or hovering flight, or from a perch, they nearly always make the kill on the ground.

In a natural habitat, buzzards perch at the top of trees to survey the surrounding fields. Their brown-and-white pattern camouflages them quite well so it's quite common for walkers to inadvertently disturb what turns out to be a huge flapping monster just feet away. Telegraph poles provide a perfect alternative to trees without any cluttering branches so buzzards can often be seen perched on the top, unfazed by cars passing beneath.

Buzzards breed once they reach 2-3 years old. During their breeding season in spring, male buzzards create spectacular aerial displays to impress females by soaring high into the air and dropping suddenly towards the ground. The birds then pair for life.

A pair of buzzards have a territory which includes a number of possible nesting sites which can be as many as 20. They move nesting site each year which prevents a buildup of nest parasites such as bird fleas. The new nest is decorated with fresh green foliage.

The name "buttercup" is thought to have come from a mediaeval belief that cows eating the flowers gave butter its yellow colour. In fact this couldn't be further from the truth as the plant contains toxins which make it taste acrid and is therefore avoided by grazing animals.

The Latin name of the buttercup, Ranunculus, means "little frog" and said to be because the plants like wet conditions. It is thought it may have come via a derogatory name for people who lived near marshes!

There are a few different species of buttercup. One of most common is meadow buttercup (unsurprisingly found in meadows!) which is the tallest member of the family. Another common one is creeping buttercup which as the name suggests spreads through rhizomes so is more likely to be found in dense clumps in damp places. Its leaves are also more golden and glossy.

Meadow buttercups spread across a field relatively slowly as most seeds fall quite close to the parent and although it has a creeping root system capable of propagating new plants, this only extends a fairly short distance from each plant (unlike creeping buttercup which has a much more extensive root system). Because grazing animals avoid buttercups due to their acrid taste, this allows them to accumulate over time. The combination of these factors allows the number of meadow buttercups in a field to be used as an indicator of how long it's been used for grazing.

Buttercups produce a toxin called protoanemonin, which is at its highest concentration when flowering. It is thought that buttercups may be partly responsible for Equine Grass Sickness. Fortunately the toxin is quite unstable and drying of the plant in haymaking leads to polymerisation into non-toxic anemonin. Buttercups are also toxic to dogs, cats and humans. They have a bitter taste which puts dogs off eating the plants but pollen can collect on fur and be ingested, particularly by cats when they clean themselves. A man in France who drank a glass of juice made from buttercups suffered severe colic after four hours and was dead the next day!

Over 160,000 species of butterfly and moth have been described and nearly 19,000 of these have been found in the UK. Butterflies are effectively a sub-group of moths that fly during the day. They have adaptations for this such as wings that fold flat against each other with a camouflaged underside to help them hide from predators when landed but a patterned upper surface to attract mates during flight. Whilst moths' feathery antennae are highly optimised for an incredibly sensitive sense of smell, butterflies can make use of vision so their antennae are more streamlined and are also used to measure air temperature.

The oldest moth fossils found so far are from the Carboniferous period 300 million years ago. By the Middle Triassic (age of amphibians - before the dinosaurs), moths had evolved their proboscis used to collect nectar from flowers. Day-flying butterflies were on the scene in the Late Cretaceous (when Tyrannosaurs were around). Originally it was thought day-flying was to avoid night-flying bats but it's now thought more likely that this was mainly to take advantage of the abundance of nectar that was originally targeted at bees.

A popular misconception is that a butterfly was originally called "flutterby". In fact, the name stems from the Old English word buttorfleoge which literally means "butterfly". The term "flutterby" is thought to have been coined by Shakespeare.

Exactly why butterflies were associated with butter is a bit of a mystery. One theory is that they were seen hovering over pails of milk and thought to be stealing or protecting the butter. Another is that the yellow brimstone was the species for which this name was first devised.

When a caterpillar is still developing, it grows a small group of cells - known as an imaginal disc - for each of the adult body parts it will need as a mature butterfly. When a caterpillar pupates, it digests itself, releasing enzymes which dissolve all of its tissues into a soup leaving only the imaginal discs. These then act as seeds from which the adult butterfly is resurrected.

Many butterflies taste/smell using chemoreceptors on their feet and antennae. They can detect a sugar solution (nectar) with their feet that they can feed on. Female butterflies also detect suitable caterpillar food plants on which to lay their eggs.

The red campion produces a blaze of pink flowers along hedgerows in the spring with the most intense flowering period occurring between late April and the end of June. A scattering of flowers continue throughout the rest of the summer. In the mild Cornish climate, a few plants can often be seen flowering during winter months.

Despite being called red campion, its flowers are most definitely pink - varying quite widely in shade from vibrant deep pinks to very pale. The colour is produced by red anthrocyanin compounds which are also responsible for red autumn leaves and red tinges on new growth in some plants as well as flower colours. In red campion, the intensity of the colour is controlled by a pair of genes and several other genes control the exact balance of anthrocyanin compounds within the petals. These are passed down the generations and so pale pink parents are likely to produce pale pink offspring.

The second part of the Latin name of red campion - dioica ("two houses") - refers to the plants' gender. Some plants are male and others are female. The male plants' flowers can be recognised from five yellow stamens sticking out from a protruding ring in the centre of the petals. The female plants' flowers have no protruding ring and instead have 5 curly white stigmas. These produce a white froth to trap pollen.

Red campion is also known as "red catchfly". The flowers are an important nectar source for larger pollinating insects including butterflies, bees and hoverflies. Much smaller flies drawn to the nectar can become stuck in the froth on the stigmas of the female flowers but this is not intentional by the plant (it doesn't eat them).

Red Campion seeds ripen between June and August. The seed capsule has teeth at the end which fold back when the seeds are ripe, allowing them to escape when it is shaken by the wind (known in botanical circles as "the pepper pot mechanism"). Each seed weighs only one thousandth of a gram, allowing it to be carried as far as possible by the wind. Nevertheless many end up falling quite close to the parent which is why red campion often occurs as a cluster of plants.

The genus name for campions - Silene from the often-drunk Greek woodland god Silenus whose name derives from the Greek word for saliva. The name is thought to be based on the froth on the female flowers used to trap pollen although its habitat preference including semi-shade within woodland also fits fairly well.

Red campion is also known by a few local names including Johnny Woods (from its habitat) and Ragged Jack (from its flower shape). Some are colour references such as Scalded Apples, and particularly in the southwest, Red Riding Hood. Cuckoo-flower is a reference to the time of year that it flowers. Another name - "Batchelors' buttons" - suggests it was once worn as a buttonhole by young men.

The roots of red campion contain saponins (soapy compounds) which protect the plants against microbes and fungi. These compounds make it easier for large molecules such as proteins to enter cell membranes. This has the potential to increase the effectiveness of immunotherapy against cancer by allowing immunotoxins to enter the cancer cells more easily.