Francine Toon spent two years of her childhood in the Scottish Highlands, near a town called Dornoch – “the last place in the UK to execute someone for witchcraft,” she says with a shiver.

Toon and other kids played in nearby Clashmore forest, frightening each other with stories about ghosts, or serial killers, or babysitters who meet horrible ends. “They made a big impression, those stories,” she says. “When it came to telling them myself I enjoyed embellishing them, and this gave me a sense of control over the thing that was scaring me. Writing Pine, I realised I was doing the same thing.”

Born in Canterbury in 1986, Toon lived in England and Portugal before moving to the Highlands when she was nine. The family moved to St Andrews in Fife two years later, but the northern wilds have haunted her ever since, and form the backdrop to her debut novel. Ten-year-old Lauren lives in a remote house with her father, who struggles with alcoholism. Her mother disappeared long ago – all Lauren knows is that she “was a healer and different to anyone else”. Ostracised by the other children and pursued by the whispers about her mother’s vanishing, Lauren comforts herself with tarot cards and a handwritten book of spells that belonged to her female forebears. When locals start seeing a silent stranger, it seems only Lauren is able to remember her visits. What follows is a chilling tale of isolation and trauma, filled with precise evocations of the natural world.

Magic feels all too likely, even logical in the remote rural setting of Pine, where Toon writes that Lauren’s dad Niall can imagine his daughter grown up and “no longer [having] to reassure her that kelpies are imaginary. Selkies, though, are almost real.”

In the world of the novel, the membrane between reality and folklore is thin. “You feel very small in that landscape of dramatic hills and forests,” Toon says. “Especially as a child.”

Now an editor at Sceptre, she recalls being taught about selkies at school, how they shed their sealskin to assume human form. And when you’re at the beach, a seal popping up “could easily be the head of a person”.

“I can see why people came up with those myths,” she says. “A friend might make up stories about a local woman being a witch, and she’d be telling this as if she was believing it herself. But even though this wasn’t true, was just children telling stories, you’d also be told a witch was executed in the nearby town. And that story would be true. The sense of the unknown, and the similarity of folklore and actual history surrounding the area, make the blending of myth and reality quite blurry.”

This in-between zone has proved fertile ground for fiction, Toon says, with female writers in particular turning to stories of witchcraft. “I always think of witchcraft-related spirituality and tarot, and even things like horoscopes, as the spiritual side of feminism if people want to seek it out. It’s female-centric in its beliefs. It’s outside of the normal patriarchal structure.”

Just as the writer and her friends found a sense of control in shaping stories about the things they feared, Lauren finds control in her life by reading the tarot, Toon adds, which is a sort of storytelling itself. “Away from its dark history, the figure of the witch has the association of an empowered woman who isn’t necessarily tied to marriage. Who doesn’t have the same fears as women in terms of being able to look after herself. In this book I was preoccupied by the idea of vulnerable women, women who’ve disappeared or women have been abducted.”

Lauren gradually understands that her mother didn’t want to leave her family, and that she will never be able to come back – a realisation that is made all the more chilling by the theory Lauren hears from two local teenagers. Then one of them goes missing, too.

As a teenager in St Andrews, Toon recalls a man who pulled up beside her in a car when she was on the way to school.

“He asked if I wanted a lift to school, saying he knew my dad,” she says. “But he didn’t say my dad’s name, and he was driving in the wrong direction to where my dad worked. Something made me say I didn’t need a lift, even though it was raining and I’d be late for school. That incident made me think about how vulnerable teenage girls can be. Especially in wilderness spaces.”

But such remote places are where witches are truly at home, Toon continues, citing a scene from Andrew Fleming’s 1996 film The Craft where four teenage witches go out into the countryside to have a picnic and perform rituals. “A bus driver tells them: ‘Watch out for the weirdos.’ And they say: ‘We are the weirdos.’ They don’t have any fear about going into that sort of space. It belongs to them.”

• Pine by Francine Toon is published by Doubleday