I have had a long relationship with the Sandy Stiltball (Battarrea phalloides). It is one of Britain’s scarcest toadstools, and also one of the oddest. It looks as if it is cobbled together from several different kinds of fungus. The fruit body arises from an ‘egg’ as if it were going to develop into some kind of stinkhorn, or possibly something like the Death Cap. But then a dry, brown and rather shaggy stem a foot high appears, which is unlike that of either stinkhorn or toadstool – it looks almost like a wooden stick. Then, to crown it all, there is a small puffball perched on top as a cap. It’s a crazy, mixed-up mushroom! A closer look reveals that the cap is actually a mass of cinnamon-coloured spores, making an imperfect umbrella a few centimetres across. The fruit body arises from a cup-like volva hidden in the ground. I had wanted to see this fungus in the flesh ever since reading about it as a youngster in John Ramsbottom’s Mushrooms and Toadstools. Its exotic features are made even more glamorous by its rarity and unpredictable appearance: here skulking under a hedge bank, there tucked inside a hollow tree. It is a Will o’ the Wisp of the fungus world, challenging searchers to find it, only to pop up some place where it was least expected.
More than thirty years ago I first learned where Battarrea could be seen in all its eccentricity. I have had a long association with the easternmost county of Suffolk, and particularly the stretch of country adjacent to the coast between the small towns of Aldeburgh and Southwold. The Suffolk Wildlife Trust advertised what was claimed to be the smallest nature reserve in Britain – a single hedge bank by the road adjacent to Blyford Church – from which emerged many examples of the elusive fungus. East Anglian churches are nearly always set on slightly higher ground, as much of the landscape was once dominated by marshland. The older churches are constructed almost entirely of flint, because it is the only building stone available locally, although the arches and coigns are predominantly made from imported limestone blocks (many of which came from France after the Norman Conquest), as flint is practically useless when it comes to making corners. Blyford Church is a typical example of its kind. Most of the churchyards in East Anglia have never been fertilised, and the graves have been left alone to rot away over the centuries. This kind of neglect is good for the fungal tribe.
Blyford Church was once surrounded by elms, but Dutch elm disease had removed the larger trees, the dead remains of which could be seen poking out in places from the hedge bank. When I went there, six examples of the Sandy Stiltball appeared along a few metres of the bank, poking out beyond the grass. I had to blink several times to ensure that they were real. They really did look like an amalgam of toadstool and puffball. A few more old dry, brown stems remained from the previous year’s crop. These fungi were evidently remarkably persistent. The drivers of passing cars looked curiously at this odd fellow apparently staring intently into an ordinary hedge bank; there was nothing unusual about this site apart from the fungi. Very sandy soil was evident: this part of Britain is also geologically the youngest, and unconsolidated sediments underlie much of it. Because sand drains readily, the site was also very dry, which is not usually favourable for fungi. Since Battarrea is a saprotroph, it was a reasonable supposition that it was feeding on the wood of the dead elm. There was plenty still to go.
I returned to Blyford Church over the following years, and the Sandy Stiltball repaid me by showing up, but gradually the numbers of fruit bodies decreased, and then they were seen no more. I assumed that my relationship to Battarrea had come to an end; but I was wrong.
In the summer of 1998 I was back home in Oxfordshire and walking on one very wet day along an ancient footpath near Henley known as Pack and Prime Lane, in the Chiltern Hills. Allegedly the name of the track was derived from a time when a traveller was advised to pack a pistol and prime it to protect himself from footpads and ne’er-do-wells. A dangerous soaking was more likely on that day, and a generously proportioned oak tree offered shelter, and invited me to notice a Sandy Stiltball emerging from a low bank just behind the tree. I could hardly believe my eyes, for it had never been recorded in Oxfordshire before. The specimen was collected to send as a voucher to Kew Gardens’ mycological repository. I must have presented a curious sight rushing back home cradling my booty sheltered inside my coat while water cascaded down my back and my hair was plastered to my head. The written account of the discovery noted that there was nothing sandy about the locality, though it was a dry bank like the other places the Stiltball favours.
When the COVID pandemic began to recede we were allowed once more to make short journeys in the area around Henley. Just over the Buckinghamshire border the small village of Hambleden is the perfect brick-and-flint cluster of cottages arranged around a chalk stream and a fine parish church, all set in an unspoiled valley flanked by beech woodland. It has been used in countless period television dramas wherein Miss Marple or Lord Peter Wimsey nails the verger as the culprit. The old churchyard had the ‘feel’ of somewhere that should yield mushrooms. I was as surprised as delighted in finding the Sandy Stiltball there, in a corner right under a yew tree: three fine specimens in tip-top condition. The members of the Bucks Group of mycologists were alerted, some of whom came to worship the rarity. It could have been that the dense canopy of the yew made the soil very dry beneath the tree, but there was no sand near this locality either. I was starting to prefer the common name used in North America – Scaly Stalked Puffball – one that did not explicitly tie it to sand. Whichever name is preferable, I doubt whether anyone could challenge me for the Most Battarrea in Britain Medal, although it is unlikely that there would be many other contenders for the title.
In the 1990s I also saw the Sandy Stiltball (or whatever) halfway around the world. When I was looking for trilobites in the Great Basin in western USA, there it was by the side of the highway, emerging from the ground in the semi-desert. Much of this area comprises vast valleys where a few choosy cattle browse the sparse vegetation to produce what may be the best steaks in the world. By this stage I was quite insouciant about the strange fungus. It is not uncommonly found in semi-arid regions in North America, and particularly where I was now working. My discovery did suggest the reason for the most important adaptations of this fungal curiosity. It is specifically adapted to dry conditions wherever they occur. It keeps itself all wrapped up in a cosy subterranean ‘egg’ until ready to emerge. When the stem expands it is dry and hollow, and the spore mass on top expends no energy on making a fleshy cap. Implausible though it may seem, Suffolk and Nevada can be similar, especially where the former has porous, sandy ground. It is rather remarkable that the original descriptions came from British material, a country where it is so rare. The botanical savant Thomas Woodward found it near Bungay in Suffolk in 1783 and by 1785 it had received the name Lycoperdon phalloides, acknowledging its odd mix of puffball (Lycoperdon) and stinkhorn (Phallus) characteristics. The genus name Battarrea appeared later, in 1801. Whether subsequent examples are collected from the USA or Africa, the reference material typifying the species remains that from Suffolk, England.
It does seem extraordinary that the same fungus can be found on either side of the Atlantic Ocean and across half a continent. When I cautiously picked my way through the cholla scrub in Nevada, all the plants – the fragrant sagebrush, tough creosote bushes and fearsome cacti – were completely different from those I knew in Britain; only the Stiltball was familiar. It was the biogeographic joker in the pack. To my surprise a few other fungi were tucked under the scrubby vegetation, for even semi-deserts have dead roots underground that can feed mycelium after rainfall. One fungus rising from the ground looked like a white ‘button mushroom’ the size of my fist that had refused to open up, presumably remaining closed to save what moisture it could while it completed its life cycle. I could not identify it then, but the spores inside had evidently ripened, without the fruit body turning into a regular toadstool. I could find no evidence of gills when I broke one specimen open, but the spores had apparently been produced on a slightly spongy internal tissue. It had a stout, rather tough white stem. When it matured it effectively became just a bag of spores on a stalk.
Judging by the white cap and very dark colour of the spore mass, I had wondered if it could even be related to our familiar Agaricus mushroom of field and commerce. It was assuredly another fungus springing a surprise and it was not until I had my books to hand again that I found a possible name for it: Agaricus deserticola; its relationship to the typical mushroom of the supermarket shelves had been confirmed by DNA analysis in 2004. The Great Basin had presented me with examples of what are termed secotioid fungi, in which the usual method of spore dispersal from the gills has been abandoned in favour of a kind of arrested development, with spore production internalised. This adaptation is all about saving water to help survival in arid environments by ‘boxing in’ the mechanics of propagation, and is yet another astonishing example of the inventiveness of the fungal kingdom. It could have been mistaken for a puffball.
One more mushroom remained to surprise me in the Nevada scrub. The American mycologist David Arora described it thus: ‘To the feverish, sun-fried, dust-encrusted fungophile driving deliriously across the monotonous mushroom-meagre desert while dreaming of cool coastal pine forests bulging with boletes and flower-filled mountain meadows overflowing with Agaricus, it is likely to be mistaken for a miraculous mirage or wistful hallucination.’ What it does look like is a foot-high, slender, ghostly pale drumstick emerging from dry ground, often in small groups. It has a white, rather scaly cap in the shape of an unfurled umbrella and a long, distinctly spindly stem with a bulbous base – but the cap never opens. No mirage this, but another specialist for desert life: Desert Shaggy Mane, Podaxis pistillaris. It, too, has traded in a conventional lifestyle as a toadstool in favour of keeping its cap closed up until its whole spore mass is ripe for dispersal.
Nonetheless, there was something about the shape of this Shaggy Mane that reminded me of another toadstool. This fungus had what birdwatchers call the ‘jizz’ – the overall gestalt – of another, familiar mushroom, the Shaggy Inkcap (Coprinus comatus). Not only the scales on the surface of the cap, and its deep spindle shape, but even the dark colour of the spores resembled a fungus that commonly grows from buried wood in England, where the climate is as wet as the Great Basin is dry. Its other common name is Lawyer’s Wig, which is not a bad description of how it looks when it freshly appears on lawns and in flowerbeds in England, though it is not long before the cap dissolves into a wet, inky mass of spores. It looks as if the strange fungus poking out of the ground in the desert must be another specialist version of a familiar one, and molecular evidence has recently confirmed that inkcap relationship of Podaxis. It is evident that several different mushrooms evolved similar solutions to living and reproducing in very dry places where mushrooms seem to have no place by rights – an example of evolution on parallel paths if ever there was one.
Like the Sandy Stiltball, the Desert Shaggy Mane has an extraordinarily wide geographical distribution. I was to meet it again when trilobites took me to the remote outback in Queensland, Australia, where the last thing you expect to see in the dry plains is any kind of fungus. It appeared among the scrubby mallee gums in a vast area of semi-desert visited by dingoes and kangaroos but hardly a human. Old men among the Aboriginal tribes are reported to have used the spore mass to darken their white hairs – a strange parallel to the long use of inkcap ‘ink’ as a pigment in England. Most surprising of all was to find it on the dry side of the Hawaiian island of Maui, growing from volcanic debris; I discovered it while researching my book The Earth: An Intimate History, when fungi were the last thing on my mind. Hardly any other terrestrial organisms have such a spread, which poses interesting questions. The endemic floras of arid Australia, Maui and the Great Basin have absolutely nothing in common, so how does a fungus break all the rules of biogeography? It seems implausible that Podaxis was spread by human agency, even though there are well-documented examples of fungi being moved across much of the world, like the Devil’s Fingers (p. 155) from New Zealand to Britain. The remote areas in which the Desert Shaggy Mane grows seems to make this unlikely; very few people go off-road in either the Great Basin or the Australian outback.
Yet it also stretches the imagination to think of wind-borne spores travelling the immense distances involved. Most fungi shed the majority of their spores quite close to their fruit bodies; only a very special breeze would take them thousands of kilometres. Could the species have spread by way of a series of arid ‘stepping stones’ – Maui being the Pacific link in the chain? The remote Hawaiian Islands are, however, an overflowing cornucopia of introduced species, most of them disastrous for the native organisms, so if it were to have been introduced anywhere this might be the place. Podaxis was first noticed by Carl Linnaeus in 1771, and possibly first recognised scientifically in Australia in the early twentieth century, so there is time for an alien introduction, although it is as likely that it had simply escaped attention ‘down under’. The Desert Shaggy Mane looked so well adapted to both its outback and Nevada homes that it is hard to believe it could be other than native to both. I have not yet had the opportunity to see it in its reported South African home but I can almost visualise the habitat in my mind’s eye.
Stiltball, Desert Mushroom and Desert Shaggy Mane would once have been classified within a great group of fungi termed Gasteromycetes (‘stomach fungi’), which included basidios that develop mature spores within an enclosed ‘bag’ of various shapes and sizes – and hence differed from the gill-bearing agarics that release their spores directly into the air. Puffballs, earthballs, earthstars and even stinkhorns were once all placed in this great group. It would have been tempting to call them ‘gasteros’ here; but that does not work any more. It is now clear that not all these ‘stomach fungi’ are closely related – they have a number of separate origins from different ancestors and can no longer be lumped together. It was as if brown bears and koala bears had once been placed in the same category because of their general bearishness, when now we know that the larger bear is a placental mammal and the smaller a marsupial, and so they do not belong in the same taxonomic drawer. Classifications reflect knowledge. They change with advances in understanding, and time and again the relatively recent availability of cheap DNA sequencing has placed many previous assumptions about fungi under the molecular microscope.
All of which is a preamble to stating that the three peculiar fungi that grow in arid climates we have visited in this chapter are all agarics. They belong in the same group as Field Mushrooms, waxcaps and Death Caps, for all their bizarre attributes. They have similarities at the molecular level that place this beyond question. It is an extraordinary thought that any kind of puffball might have evolved from a conventional mushroom – they look so different. Even though nature is full of dramatic evolutionary gymnastics, this one could look like a somersault too far. So consider this scenario. On several occasions in the long history of the fungi, the kind of strategy used by Podaxis to ripen its spores ‘under cover’ may have led to specialised fruit bodies that were in no hurry to spread them. The outer hyphal layers of this modified mushroom became the longer-term cover (peridium, often in two layers) for a ‘bag’ of spores, to be released at leisure. Some kind of mouth (ostiole) developed at the apex of the fruit body to allow the spores to escape when they were ready to do so. By this point you have a typical puffball.
The most important evolutionary step was permitting the spores to mature from basidia retained inside the ‘bag’ in a tissue (gleba) woven from mycelium. Young puffballs are often firm inside and the solid interior is white. As the spores begin to ripen the interior tissue becomes soft and yellowish. Eventually all that remains are mature brown spores, often accompanied by the spongy mycelial ‘struts’ (capillitium) that allowed the interior to develop, the whole still enveloped in a membrane (the inner layer of the ‘skin’), which is by now quite soft and pliable. The puffball is ready to puff. The touch of a raindrop may be enough to release a cloud of tens of thousands of spores from the apex, but a mature puffball can endure for weeks, or even months, so turning into a repository for reproduction for a greatly extended season compared with a conventional mushroom. The puffball can cope better with drought than its gilled contemporaries. It is still quite a step to evolve a specialised puffball from an ‘unopened’ mushroom like Podaxis, not least that this modified mushroom does not ‘puff’ – it simply decays into a mass of black spores – but it does provide a model to explain how and why natural selection might work to push the design of the fruit body in the puffball direction.
The puff of brown ‘smoke’ that comes from quickly squeezing a mature Common Puffball (Lycoperdon perlatum) remains the best way to demonstrate the reality of spores to a group of fledgling mycologists. It often elicits a delighted gasp. Within a few seconds the cloud has dispersed into the air, and this is a good time to explain how those spores are still everywhere about us no matter how invisible they are, carried on the whim of the breeze to find exactly the right place to germinate. Even in the middle of winter in a damp wood slightly sad-looking, deflated specimens of the Stump Puffball (Apioperdon pyriforme) clustered on rotting wood can still be persuaded to perform, if a little half-heartedly.
The Giant Puffball (Calvatia gigantea) is probably the world’s most conspicuous fungus. Huge, bloated, white and shining, and often much larger than a football, it emerges singly or in clusters in fields or on the margins of woodland among straggly nettles. It gets noticed. I have more than once spied one from a passing car and stopped to collect it, ignoring the terrified protests from my family. Local newspapers have been known to feature a monster specimen in a photograph in conjunction with a small child for scale. I have seen it growing in graveyards and in the central reservation of a motorway (the one I didn’t pick). It does not last long in its pristine whiteness, gradually yellowing, losing its outer skin and becoming much less conspicuous. Eventually, it adopts the umber brown colour of the mature spores and then it hangs around for months in fields and hedge banks, supported by its mycelial skeleton, as light as a soufflé. Passers-by might give it a desultory kick, and then a cloud of spores will be released in wisps of diffuse smoke. This puffball does not have a special ‘mouth’ to release the spores, nor a clearly defined stem, which makes it rather different from the majority of its tribe. Most of the walkers who notice the brown ball will make no connection between this strange object and the white globes of its heyday.
The Giant Puffball is a sphere of superlatives. Consider the number of spores in one good-sized fruit body: there are estimates that such a specimen might yield 7,000,000,000,000 – seven trillion – spores (I have never counted them myself). Each spore is round and slightly spiky and about five thousandths of a millimetre across. So upon this micro-dust depends the future of the species. To put it in context, our galaxy the Milky Way has about a hundred billion stars, so a single puffball is seventy times as prolific. By the same token this puffball must have one of the lowest fertility success rates of anything on Earth, since there is (to put it generously) no more than a trillionth chance of any given spore producing a new mycelium and puffball. My coral specialist friend tells me that some reef corals release unfathomably large numbers of tiny larvae during a brief spawning episode, though these are many times larger than a spore – but the stratagem is comparable, since the job of the larva is to find exactly the right spot to develop in an endless ocean: safety in vast numbers. I believe that the Giant Puffball may be commoner than it once was, as it seems to tolerate nitrogenous conditions that are becoming more prevalent. As the edges of artificially fertilised meadows become full of nettles, the Giant Puffball can still find a home. It can only be eaten when it is very young, while the interior is still as white as a cheap supermarket loaf. If sliced and fried in butter till it is golden on both sides, it makes an excellent companion for scrambled eggs. If the inside has started to go a little yellowish the taste will already have a nasty acidic edge.
In fields with short grass in late summer a common sight is what look like scaled-down Giants – Grey or Brown Puffballs (Bovista). They are particularly found on golf courses, where they must infuriate players who mistake them for golf balls in a prime position to make it on to the green. At the same stage they can look like button mushrooms from afar and there have been occasions when I have sprinted across a fairway, basket in hand, only to be disappointed. As it matures, Bovista loses the white outer layer of its covering and the tough inner layer darkens to lead-grey or brownish according to the species. When fully mature this puffball becomes almost feather light and blows about in the wind, the spores escaping through a ragged hole in its surface. I have found it stranded in the middle of a road. It becomes the fungal equivalent of tumbleweed – those dried-up herbs of several species that bowl along southern American highways in the wind, which helps to distribute their seeds. Nature seems to be full of such similes.
The pestle-shaped Common Puffball is also edible when it is young and white inside, but I think it is hardly worth the trouble. Like all the true puffballs it is a saprotroph, and can be found on the ground by roadsides or in woodland, and in all weathers, so it is not fussy. It also has a worldwide distribution, which must surely testify to the efficiency of puffing into the wind, as well as its adaptability. Unlike the Giant Puffball, it has a stout stem that remains a stem and is not part of the fertile head. When it is young the top of the puffball is covered with little pyramidal warts of two sizes; these have a beautiful regular, but scattered arrangement. They can easily be brushed off the surface. As the puffball ages the warts leave behind a polygonal pattern as the fruit body changes from white to brown. At this stage it is a good puffer.
Several related species have different sizes and arrangements of the surface decorations, which is one of many reasons to always carry a hand lens into the field. In our local beech woods an attentive forayer can have a close encounter with one of the less common and most appealing puffballs. Tucked down into the litter it looks very like a small, pale-brown, rolled-up hedgehog – a ball of spines, no less. This is the Spiny Puffball (Lycoperdon echinatum) and a little scraping around reveals the stem anchoring it to the woodland soil. I can think of no reason why resembling a hedgehog should confer any advantage upon this pretty fungus. The resemblance is only superficial as the spines are not particularly sharp.
Other kinds of puffballs are frequently found along path sides near Lycoperdon. The Common Puffball is often outnumbered by rounded, yellow or pale-brown fruit bodies that tend to form clusters, looking somewhat like potatoes emerging from a bank, or even from hard ground. A pair of them side by side can look distinctly testicular. In dry summers these fungi are often the only specimens that can be brought home, and they occasionally occur in such numbers that the ground appears to be blistered. These earthballs (Scleroderma) are pretenders. They are not true puffballs. The first thing you notice is that they have a different texture – they are hard when fresh, more like a genuine golf ball than a Field Mushroom. The flesh inside is marbled, resembling that of black truffles. They do not smell pleasant; the odour is sometimes described as rubbery – although I am not quite sure what that means. They are without a stem, but attached to pale mycelial cords in the ground, although some species do extend downwards into a gnarled ‘pseudostipe’. Earthballs are designed to be tough customers. The commonest of them (S. citrinum) has a very thick yellow skin with a scurfy exterior – if you cut one through, the outer skin surrounds its innards in the same way the peel of a Seville orange encases the juicy fruit. Unlike the puffballs, the central spore ‘factory’ (gleba) is soon black, but remains very firm for a long time. Cavities develop within it that are lined with spore-producing basidia. It can take several months before the interior of the earthball is ready to become a puffer when the black spores are fully ripe, and the supporting tissues have degenerated. It then opens through a large, ragged vent in the top to make a crude cup. Every year I give a talk and lead a foray in October in the Harcourt Arboretum associated with Oxford University, at the edge of the attractive village of Nuneham Courtenay. On one occasion I was caught out in front of a small crowd by trying to make an earthball puff. The cup collects rainwater. My enthusiastic squeeze to demonstrate puffing projected a black, spore-filled soup into my face. It was the mycological equivalent of the custard pie. The small boys in the party were greatly amused.
There are many differences between these puffing pretenders and the true puffballs. They are not primarily saprotrophs, instead they are mycorrhizal partners with trees, which is why they accompany birches in such abundance in the part of Suffolk I know well. Their spores ripen in a different way and are about twice the size of those of puffballs. These terrestrial balls are also somewhat poisonous. They do not blow around like tumbleweed at any time in their life cycle. Their empty sacs endure for a long time in situ, sometimes breaking up into a crude star that becomes stained green with algae, at which point few would be able to guess their fungal persuasion. Earthballs have a separate evolutionary origin from other puffballs. DNA analysis has proved that they share a common ancestor with the fungus with which this book began – porcini. These inedible, tough, spherical survivalists are distant cousins of the boletes, the fleshy kings of the table that are all too soon decayed. The pore-bearing object of culinary desire has an undesirable alter ego, one that nobody wants to eat, not even snails. This may seem an astonishing transformation, but we have seen it before. It seems plausible that the processes of natural selection that made puffballs out of agarics made earthballs out of boletes. This would entail altering development so that spores matured while still enclosed, in the manner of the desert agarics. Certainly, earthballs cope well with dry conditions compared with their fleshy relatives – their outer skin ensures that they do not dehydrate, and they appear even in heat waves when the hopeful hunter searches in vain for porcini or one of its tasty relatives. They crouch down low in the ground, often partly buried. I sometimes think they are halfway to being truffles. Indeed, unscrupulous traders have used them to impersonate real truffles in patés and sauces. Their ingestion is known to cause stomach ache and nausea, but does not result in fatality, so death by earthball remains an improbable scenario.
* * *
On the north west side of the Chilterns the chalk scarp looks down on the fertile Aylesbury Plain below. For southern England the scarp is unusually steep, which has allowed it to escape the agricultural exploitation that has altered so much downland countryside. Sheep still graze on the slope and their tracks criss-cross the hillside. Towards the top of the hill, rock rose still blooms and has its own associated fungi in due course. Fragrant wild thyme and oregano decorate the tops of anthills, and the occasional orchid donates a splash of colour in June. On the flanks of Shirburn Hill above Watlington there is a strange, dark-green expanse of woodland hanging on to the steep side of the hill. On overcast days it can look almost black. It is a miniature forest of box trees (Buxus sempervirens).
A few years ago my wife Jackie and I were involved with a survey of such woodland, and found that most box trees were probably planted as game cover in large estates. These rare, dense, chalk-slope woods are something different. They are likely native. Box trees grow very slowly and spread by natural layering wherever branches touch the ground. In many places, as in Box Hill, Surrey, the hard boxwood has been used for centuries to make precision wooden tools – it is one of very few woods that can make a screw joint – as well as wind instruments and the boxwood rulers of the pre-plastic era. There is still a demand for the wood today, particularly from baroque revival orchestras. Such native box woodland is very densely packed. The outer branches lean down to the ground, making the whole mass of trees well nigh impenetrable. Nothing else grows there, except an occasional struggling mountain ash. Once the fortress has been breached by pushing aside branches and squeezing through, a strange world appears inside: the yellowish trunks of the trees make a series of supports as if the overarching canopy of leaves were a kind of enveloping tent. It is very dark. A hobbit would not seem out of place. Because so little light reaches the ground almost nothing grows there. It is not a little eerie.
When I ventured into this wood with a surveying party in the autumn of 2017, it did not seem the best place to prospect for fungi. People were stumbling around in the half-light getting poked by dead branches. The woodland floor appeared unpromisingly dry. Then the silence was broken by an excited cry: ‘Earthstars!’ Of all the puffers, the earthstars (Geastrum) are the most beautiful, and their discovery always causes a frisson of excitement. Here was a group of the largest and commonest species, the Collared Earthstar (G. triplex), each one a couple of inches or more across. A pale-brown, central spore-carrying sphere, with a distinctly projecting mouth (ostiole), was surrounded by six to nine outspread arms, like those of a starfish; on some specimens the arms had curved back and slightly elevated the fruit body. Several showed a collar around the spore sac. It was a delightful group. A tentative prod stimulated the expected spore puff. These earthstars had happily matured under this almost lightless, dense canopy. Further searching revealed some immature individuals, looking rather like onions with pointy ‘noses’, hunkering down on the forest floor. It was clear how the earthstar must have matured by the rays peeling back, almost like a flower opening from a bud, the outer layers of the ‘skin’ (periderm), making the star that allowed the inner one to achieve prominence as a specialised sac helping the expulsion of the spores to the atmosphere. ‘Earthflowers’ would have been as good a name as earthstar.
Hardly five minutes had passed when another cry went up from a different part of the wood: ‘Weather Earthstars!’ Now this was really exciting because this earthstar (Geastrum corollinum) is very uncommon. We hoped it might be a ‘first’ for Oxfordshire here in this apparently most unpromising site: a group of three or so, about half the size of the Collared Earthstar but with a very prominent conical ‘mouth’ where the spores were expelled. This particular earthstar has a remarkable ability. When the weather is dry, the arms curl up around the spore body, but when it is wet they fold back to allow spore distribution to continue. Ours was out-stretched. In the enrolled state there is perhaps no more graphic example of water conservation in fungi. We carefully collected one sample to be sure of our identification, but we would bring it back to finish its work. Within a few minutes a third earthstar was discovered: the Striated Earthstar (Geastrum striatum), a smaller, elegant fungus with a pointy mouth scribed with parallel grooves, and the whole, rather small spore-bearing flask born aloft on a stalk. Not many of our party had seen it before. Nor did it stop there: eventually, we discovered that a total of five (possibly six) different earthstars enjoyed a living in this gloomy woodland – more than had ever been recorded together from a single locality. It was proving earthstar heaven.
Now was the best time for our group to discuss why this particular place so suited these peculiarly engaging, and almost certainly saprotrophic fungi. It was implausible that there was any particular association with box trees as mycorrhizal partners. The most noticeable feature of the site was the absence of almost everything else. The ground was bare except for box debris and soil. There were hardly any other mushrooms or toadstools to be found; the only common fungus was an orange patch that could be observed on many of the standing dead branches; I later identified it as Peniophora proxima, Box Crust. Hence it seemed likely that the absence of any kind of fungal competition had helped our earthstars to flourish (though it was always possible that there may have been other species only present as mycelium). The dry habitat may have eliminated potential competitors. Our Weather Earthstar was already adapted to conserve water by spreading or recurving its ‘starfish’ arms according to the meteorological conditions. All earthstars could bide their time until it was time to ripen their spores. There were also virtually no flowering plants in this dim underworld – except the remains of a foxglove or two, perhaps. Even that possible competition was removed. I like to think that the earthstars were able to colonise a habitat that discouraged virtually everything else, bringing their own curious beauty to a dark and secret place.
Shiplake Church is a pretty brick-and-flint building of medieval origin and largely Victorian restoration not far from the River Thames on the Oxfordshire side. It is close to an ancient manor (now a private school) and somewhat further removed from an affluent riverside village that is home to many commuters and their families. As in Blyford, churchyards and graveyards are profitable places to search for interesting fungi. They have generally escaped artificial fertilisers and the grass around gravestones has been mowed often enough to keep fertility low and encourage a mixed sward. In Shiplake churchyard a splendid cedar tree dominates the gate that leads to the church. The dense canopy of the cedar is such an effective umbrella that virtually nothing will grow underneath it. A dry patch of needle duff encircles the trunk of the tree. It might sound a little like Shirburn Hill under the box trees. In November 2008 I was thrilled to find more than twenty small earthstars in this dry area where nothing else grew.
These examples were different from all I had seen before because the spore bodies had been lifted from the ground on stilts! Though they were not much taller than an upside-down eggcup, there was something inescapably anthropomorphic about these fungi, as if they were tiny homunculi trying to break free of the ground. Each one had a strikingly lead-grey round ‘head’ the size of a small marble carrying a narrow pyramidal ‘mouth’ for the spores to exit. On closer examination it was clear that what had lifted up the ‘head’ were the rays that in most earthstars spread horizontally to give the typical starfish-like appearance. Here they had curved steeply downwards to achieve an elevation that would help spore release clear of the litter. When I dug one earthstar carefully out of the needle duff, I discovered that its structure was more complicated: each of the arms was attached to a point around the edge of a thin bag buried somewhat in the soft ground. Needles adhered to the outside of the bag. So the earthstar was lifted up twice. The number of arms was variable – four to seven in this collection – and the ‘skin’ enclosing the spore body must have been composed of several layers, the outermost of which formed the basal bag, the inner one the elevated arms. I could now envisage how this extraordinary earthstar must have arisen after emerging from an initial ‘egg’, raising itself up on its arms like a jack-in-the-box to break free of the needle cover. It was another wonder of the fungus world.
With the aid of British Puffballs and Earthstars, a 1995 publication of the Royal Botanic Gardens, I believed I should be able to identify this discovery in short order. There were several species illustrated that had some claim to be the same as mine – a small one, Rayed Earthstar (Geastrum quadrifidum), was about the right size and looked generally similar but four rays were usual in this species, the ‘bag’ was not well-developed and the ‘mouth’ was not surrounded by grooves. One species stood out as having a similar human-like appearance, complete with basal bag, and it was very rare: the Arched Earthstar (provocatively named scientifically Geastrum fornicatum). I already knew about this earthstar from an illustration in Roger Phillips’ famous photographic guidebook to fungi, first published in 1981, and it must have been registered in my unconscious mind as an object of desire for many years. Could I have found it at last? It certainly looked similar in many ways. There were some reasons to be doubtful: not only were my specimens generally smaller, but the Arched Earthstar was typically four-rayed (most of mine had more), and the rays seemed to be more deeply split, and the covering on the spore sac was apparently not leaden grey as on the Shiplake specimens. I believed this was different. It was one of those occasions when the best thing to do is to dry a specimen and send it to Kew Gardens, where the reference collections for British fungi are conserved. I received a note back describing it as probably an unusual specimen of the Rayed Earthstar, Geastrum quadrifidum.
That might have been the end of the story, but there is another, and possibly final paragraph. In 2015 a scientific paper was published revisiting the European earthstars using modern scientific techniques, including DNA analysis.[1] A new species was erected for British specimens found in a churchyard in Cockley Cley, Norfolk – it was named Geastrum britannicum. I suppose it might be called the British Earthstar. It was without doubt the same earthstar that I had found in numbers in Shiplake, Oxfordshire, in 2008. It was also growing in needle litter. The Metro newspaper reported it in 2015 under the banner: ‘These Newly Discovered Mushrooms Look Like Little Humans’. My misgivings had been correct – mine did not belong to any of the species named in the books I had to hand in 2008.
Although I may have been the first to wonder whether my collection was a distinct form, I was not the first person to discover it; the Norfolk collection had already been made by Jonathon Revett, a local naturalist, in 2000. I have been back to my site every year since my first discovery, and the British Earthstar has reappeared in different numbers every year. Just a single fruit body survived the drought in 2022. Since 2015 there have been other discoveries in other churchyards, so this charming little ‘hominoid fungus’ had probably gone unrecognised for many years. If this is my ‘I was right’ story, I have a balancing ‘I was wrong’ story later in this book. When it comes to fungi, the one thing you cannot be is complacent.
The strangest and rarest member of the puffball tribe is the Pepper Pot (Myriostoma coliforme). When mature, it looks generally like an earthstar, but instead of having a single mouth through which the spores can exit, this weird creation of the fungus kingdom has a number of separate openings in the spore sac, which looks as if it had been pierced multiple times by a skewer. When the dusty spores emerge, it does, indeed, resemble a pepper pot. To make things odder still, the spore sac is supported by several pillars, like the bearers of a coffin. The figures in Roger Phillips’ 1981 mushroom guide included the last specimen to be collected in Britain, from Norfolk in 1881, with the note: ‘It is hoped that the publication of an illustration of this interesting fungus will lead to its rediscovery.’
After a hundred years that might have seemed a forlorn hope, but I always carried a secret wish that I might be the one to find it again in East Anglia, closest in Britain to where it was still known among sand dunes in the Netherlands. To the general astonishment of the mushrooming world it did reappear in our islands in sandy soil in 2006, at a site not so far from its 1881 home – I am not permitted to say exactly where. The rediscovery of the Pepper Pot can be credited to Neil Mahler, a diffident East Anglian mycophile of great persistence. He had already discovered the rare Arched Earthstar and spectacular Umbrella Polypore (Polyporus umbellatus) so he had a marvellous nose for alpha fungi. It remains a wonder that he spotted the Pepper Pot from a scooter.
Remarkable and strange though the ‘puffers’ and their lookalikes might be, few of them could be described as pretty, but that is the word that crops up when people first notice bird’s nest fungi. The recent fashion for spreading bark on flowerbeds and under trees as a weed suppressant has suited these diminutive relatives of the earthstars very well, so they are now a common sight in public parks and new housing estates. They do not puff in any comparable way to the other fungi in this chapter. They do, however, begin as small spheres the size of a large lentil, at which stage they are easily overlooked, even though they may occur in swarms. When the spores are ripening, these vessels open up into little cups, and inside the cups are ‘eggs’ (peridioles) that contain the numerous spores, so at this stage they really do look like miniaturised bird’s nests complete with a neatly stacked clutch. The spores have been packaged for a special kind of dispersal. The cups are no bigger across than your little fingernail (and some species are smaller) so to fully appreciate how pretty they are you have to get close. In the Striated Bird’s Nest (Cyathus striatus) the little cups are slightly flared and subtly grooved along the inside. The eggs nestle in the bottom. The Field Bird’s Nest (C. olla) is brown and hairy on the outside. The yellowish Common Bird’s Nest (Crucibulum laeve) has many smaller eggs, and often grows in lines upon fallen sticks in damp places. There is even a species that grows on dung. The distinctive design of the nests is recruited to help dispersal of the eggs and spores. When a raindrop splashes into one of the little cups an egg is splashed out and may travel up to a metre away. After their outer covering decays, the spores released frequently germinate in an ideal place. In the Harcourt Arboretum at Nuneham Courtenay extensive patches of bark dressing under the conifers were completely covered in cups of the Striated Bird’s Nest one year, so much so that it looked as if they had been deliberately planted to please the eye.