At first I can’t make out the inscription, even though I’m searching for it. Smooth new bark has grown into the cuts, bulging around the incision, preserving the words on the trunk. I run my hand across the surface, tracing the grooves, feeling the letters: R-E-T-R-I-B-U-T-I-O-N. And below, in slightly larger hand, ‘CAMP’.

We are in the boab belt, the ‘western wilds’ of the Victoria River District in the Northern Territory, between Katherine and Kununurra. This is Ngarinyman country: near the northern end of Judbarra/Gregory National Park. It has taken us much of the morning to track down this particular boab, which rises grandly out of long, thick grass. I step back to take it in as a whole. It is immense.

It is hard not to be captivated by boabs (Adansonia gregorii). They are the charismatic megafauna of the botanical world; their bulbous trunks and knobbled limbs lend themselves to anthropomorphism. Ernestine Hill affectionately described the boab as the ‘friendly ogre of the great North-west’: ‘a grizzled, distorted old goblin with a girth of a giant, the hide of a rhinoceros, twiggy fingers clutching at empty air, and the disposition of a guardian angel’. But boabs are more than guardian angels; in remote arid areas, they are life itself. Their soft, fibrous wood can trap so much moisture that the trunk visibly swells and shrinks with the seasons. Even in drought, ‘sweet water’ can be sucked from the wood or scooped from its hollows. In the nineteenth century, certain boabs along the police track between Derby and Halls Creek had jam tins dangling from their trunks for the convenience of thirsty travellers.