| 1 | Eastern ratsnake |
Maximum length: 228cm.
In the USA, there’s no snake more likely to be found hiding in a dark tree trunk hollow than the black ratsnake (Pantherophis alleghaniensis), or its close relatives further west like the grey ratsnake and western ratsnake.
This species inhabits the US east coast, and ranges from Vermont in the north to Florida in the south. It’s a non-venomous constrictor with a thick body, which reaches a record length of 228cm.
Much of the black ratsnake’s diet consists of birds, as well as small mammals. Consequently, it has evolved excellent climbing abilities, and ascends tree trunks with ease, using the natural grooves of bark for added friction. It often raids nestling birds while they’re sleeping, tactically ensuring that the mother birds are away hunting (though it sometimes mistimes this).
The logical progression was to start hiding within trees themselves, and that’s exactly what black ratsnakes do. Black ratsnakes are regularly found hiding in dead, hollow trees, or in natural chambers within the thick trunks of living trees. In any North Carolina woodland, there’s a high chance that you’re walking past multiple black ratsnakes stashed away inside trunks, invisible to the naked eye.
Being a lumberjack is hard enough as it is, with the risk of massive falling trunks that could crush you. But in the eastern USA, there’s a very real risk that you could have a heart attack as a 2 metre serpent crawls out of a tree trunk, just as you’re stacking it in a neat pile. There’s even a risk of a black ratsnake emerging as you drive your timber truck down the forest path, and appearing in your rear view mirror, causing you to crash the vehicle in horror.
| 2 | Southern African rock python |
Maximum length: 580cm.
The most widespread python in South Africa, Zimbabwe, Botswana, etc. Alongside its central rock python cousin, this one of the top 5 longest snakes worldwide, sometimes breaking through 5 metres, with rumours of even 7 metre brutes. Despite this brute size, the southern rock python still has the power to identify a dark hole in a tree trunk, weave through and take shelter inside the tree itself, particularly as a juvenile.
The diet of this huge species includes antelopes, warthogs, white pelicans, and monitor lizards. Many African locals have mentioned the tendency of this snake to hide in empty mammal burrows, such as those of aardvarks. Tree trunks are another impenetrable shelter, which southern rock pythons eagerly invade if given the opportunity.
Southern rock pythons lack even a mild venom, meaning that there’s little risk of walking past their tree sanctuary and being lunged at. Huge individuals have attempted to hunt children occasionally, but they generally have no desire to attack human beings.
The only thing you have to fear from this species is a heart attack, if a curious python head suddenly appears from nowhere. African rock pythons have a history of reaching weird, usually unattainable places; this image shows one up a cliff 1000 metres high.
| 3 | Golden tree snake |
Maximum length: 140cm.
A harmless flying snake of southeast Asia, especially Thailand, where it’s abundant in Bangkok itself. The golden tree snake (Chrysopelea ornata) is mildly venomous and averages at 100-130cm.
Golden tree snakes are constantly leaping between trees, gliding to reach far off branches, but they also take shelter within trees. They can slither into large crevices created by branches splitting and falling to the ground, but also tiny holes, which grant them access to the hollow tree trunk chambers within. This species can access places a human being couldn’t dream of, weaving through entrances of mere centimetres.
As a thin-bodied snake with few weapons, the golden flying snake must be concerned with its safety. Thailand is home to many snake-eating (ophiophagous) predators, such as the king cobra and various birds of prey.
Golden tree snakes can position themselves between overlapping branches, using a shield of thick leaves to hide themselves. But there’s nothing more secure than a tree trunk sanctuary where a bird literally cannot fit through the entrance, no matter how much it flaps and squawks.
This species is mildly venomous, but incapable of killing human beings. There’s nothing to fear if you put your hand into a tree trunk and feel its scales brushing against you, perhaps while searching for fossilised insects in amber tree sap.
| 4 | Lichtenstein’s green racer |
Maximum length: 147.6cm.
Lichtenstein’s green racer (Philodryas olfersii) is a species found all over eastern Brazil, particularly near São Paulo and the northeasterly Paraíba region (the easternmost point of the Americas). This is a moderately venomous species which causes swelling and haemorrhaging, and has caused one confirmed death.
Lichtenstein’s green racers regularly exceed 1 metre, and shun open arid areas. Instead, they appear anywhere trees grow, from isolated clumps to fully fledged forests. Lichtenstein’s green racers appear anywhere on trees: at their foot, 15 metres high, on a mid-height branch, or nestled within secret sanctuaries inside the thick tree trunk. They like to stash themselves when not hunting, accessing the hidden hollows through tiny entrances.
Like the eastern ratsnake, Lichtenstein’s green racers commonly slither directly up gnarly tree trunks and into bird’s nests, hoping to swallow up the nestlings. According to a sighting from Campinas, São Paulo state, they’re intelligent enough to return to the same tree year after year, seeking out new birds to eat. It’s likely that they return to the same cosy tree hollows as well.
Cut down a tree in Brazil, carve up some timber and there’s a great chance of cutting into the Lichtenstein green racer’s hidden tree trunk sanctuary. How it will react to this intrusion remains to be seen. Fortunately, there’s no risk of instant death, as this species must chew repeatedly to inject its venom.
| 5 | King cobra |
Maximum length: 5.85 metres.
Unlike many on this list, the world’s longest venomous snake isn’t an arboreal or tree-dwelling species. King cobras primarily stick to the ground, in rainforests and evergreen forests receiving over 1500mm of precipitation annually. Yet there’s numerous stories of people accidentally finding king cobras coiled inside hollow trees. Thai villagers and European naturalists alike have peered in to find the brutish face of a king cobra staring back at them.
King cobras (Ophiophagous hannah) are widespread in Thailand, northeast India and Cambodia alike, yet tend to be sparser than true cobras. The likes of monocled cobras appear in inner city Bangkok, but king cobras stay away from urban zones, and generally reside in forests. This is a rare snake to construct its own nest, by dragging in assorted forest materials. Hiding in tree trunks is another surprising tendency, particularly for such a large snake.
There’s a very real possibility of exploring a Thai forest while on holiday, only for a semi-basilisk to explode out of a tree trunk towards you. If any snake could solidify the old superstition “the forest came alive and took him”, it’s the king cobra.
| 6 | Bull snake |
Maximum length: 267.7cm.
A widespread species of the western US, inhabiting Colorado, Wyoming, Montana, etc. Bull snakes aren’t as fond of trees as eastern ratsnakes, preferring open grassland, plains and the edges of crop fields. However, they still venture to forest clumps, and will happily invade the hollow centres of trees when they do.
The bull snake is actually a subspecies of the gopher snake (Pituophis catenifer), and is non-venomous, relying purely on constriction skills. It also holds the record for longest US snake ever, with a record of 267.7cm. Picking this snake up isn’t advised, as it’s known to turn vicious in a flash.
Like eastern ratsnakes, birds and their eggs are a common meal for bull snakes, and once they’ve consumed them, there’s no reason to move on quickly, if there’s a cosy dark hole they can rest in. A hollowed-out chamber within the trunk of a tree they’re already resting on is the perfect sanctuary.
In its cosy tree, the bull snake can coil up in comfort with nothing but sap and bark and woodlice for company. It can ponder the day’s activity, running through datastreams concerning the flight paths of nearby birds, and the most profitable local fields for rats and mice. It can decide whether to stick to its current location, or seek out a more bountiful neighbourhood a few hundred metres away. Then the bull snake can emerge at dawn and implement its plan of action.
Bull snakes hunt by day and rest at night, so it’s unlikely that one will lunge at you from a tree on your weekend walk in the forest.
| 7 | Scarlet kingsnake |
Maximum length: 74.0cm (maybe 76.2cm).
The scarlet kingsnake (Lampropeltis elapsoides) inhabits southeastern US states such as Florida, where it’s most likely to be found in woodlands and sparse forests. It’s also a likely snake to find hidden within trees themselves.
Rather than dark chambers, scarlet kingsnakes are particularly fond of wedging themselves behind rotting bark, especially in long strips of bark peeling away from trees. They even lay their eggs in these bark sanctuaries. This fondness for hiding behind bark strips makes them one of the easier snake species to find in a Florida woodland – if you know the secret.
Scarlet kingsnakes prey overwhelmingly on fellow reptiles, including 74% skinks and 15% fellow snakes according to one study. They reach an average length of 50cm, and are no threat to humans.
The one possible exception is triggering a heart attack, as you’re enjoying a picnic lunch and a random snake slithers out of a tree. It doesn’t help that they bare a close resemblance to the eastern coral snake. Scarlet kingsnakes are differentiated by their “red touches black, venom lack” banded patterns, instead of “red touches yellow, kill a fellow” for the eastern coral snake.
Scarlet kingsnakes lack any means to defend themselves, so stashing themselves in tree trunks is likely a simple means of shelter. They also shelter in fallen logs on the ground, and rotting stumps of dead trees.
| 8 | Black-necked spitting cobra |
Maximum length: 240cm.
One of Central Africa’s most widespread snakes, especially in Nigeria and Ghana. Black-necked spitting cobras (Naja nigricollis) have a cytotoxic bite, but more infamously, the power to spit 9.75mg venom globules into people’s eyes, and blind them for 3 days. This globule could come from overgrown grass, a bush, or more disturbingly, a tree trunk.
Black-necked spitting cobras exceed 2 metres, but are relatively thin, allowing them to weave through small gaps, and coil up cosily inside a tree trunk sanctuary. They rely on venom rather than crushing constriction, and have no need for thickness.
Many Nigerian locals have mentioned the tendency of this snake to hide in hollow trees, as well as termite mounds. This makes peering into a hole in a Nigerian tree a very risky business. Your face could get bitten, or a blob of venom could fly out. Theoretically, a globule could strike you as you walk past, although since they aim for the eyes, this would be more likely to strike you on the side of the head.
Black-necked spitting cobras are fast-moving and easy to recognise via their flared hood, and blacker appearance than the nearby forest cobra. Though agonising, victims’ eyes usually heal and regain their vision several days post spray.
| 9 | Horseshoe whipsnake |
Maximum length: 185cm.
This Spanish snake’s tendency to stash itself in tree trunks has had grave consequences. Horseshoe whipsnakes typically measure 100-160cm and are extremely common in Spain, and can prey on virtually anything. They occupy various habitats, and olive plantations are a particular haven for them, where they often rest in tree hollows for hours or even days, unbeknownst to the workers harvesting valuable olives above their heads.
This tree trunk tendency poses little threat to humans, as horseshoe whipsnakes are completely non-venomous. The one grave consequence has been the invasion of Ibiza and Mallorca, and the decimation of the native wall lizards there.
2 decades ago, there was a huge trend on the Balearic Islands for ornamental olive trees planted in gardens. These were uprooted from mainland plantations and transported across the sea, allowing horseshoe whipsnakes to slither out and conquer an all new island.
The problem is that Ibiza and Mallorca have no native snakes, and the poor wall lizards have no defensive instincts against them. Consequently, numbers of the native lizards are plummeting, and efforts are underway to eradicate the invasive horseshoe whipsnakes hunting them.
Either way, if you’re in Spain and an olive tree starts hissing at you, you haven’t lost the last tattered shreds of your sanity. The ladder snake is another olive tree stasher found in Spain.
| 10 | Annulated-cat eyed snake |
Maximum length: 103.8cm.
This South American species takes hiding in tree trunks to an industrial level. The annulated cat-eyed snake (Leptodeira annulata) is a mildly venomous species which spends 95% of its life on branches, hunting for tree frogs and their eggs. It inhabits the vast majority of Brazil, plus Bolivia, Peru, Paraguay etc. Annulated cat-eyed snakes are nocturnal, and during the day, they rest inside the best shelter available to them: small chambers within gnarly tree trunks.
One great study took place in the Pantanal wetlands of southwest Brazil. It found that the local annulated cat-eyed snakes followed a regular pattern, where they would retreat into tree trunk hollows when the sun rose, then poke their heads out again at approximately 18:30, in order to scan their surroundings.
If there’s any snake where you could sit on the grass with a camera in hand, waiting for the snake to emerge at sunset, it’s the annulated cat-eyed snake. The only tricky part is selecting the correct tree in the first place. At 18:30, your camera might be fixed on the tree in front of you, while an unnoticed cat-eyed snake pokes its head out of the tree directly behind you. Luckily, this is an abundant snake, and many can live in one area.
Leptodeira annulata is a fast, agile species, and coexists with snakes such as the Brazilian smooth snake and yellow anaconda, which prefer rivers and rivershores below the trees.