In the photography of Ackroyd & Harvey, notions of passage of time and transience are evoked through the use of a living plant material – seedling grass. The artists use grass grown from seed on vertical surfaces as a living photographic medium, which they term ‘photographic photosynthesis’. In a darkroom setting using projected light through a negative image, the emergent blade of grass has an extraordinary capacity to record complex photographic images through the production of chlorophyll. Each germinating blade of grass produces a concentration of chlorophyll pigment that relates to the amount of projected light available to it, and the strength of green produced is according to the intensity of light received. Gradual fading of the image may occur over time due to natural UV bleaching by light.Responding to ‘place’ is integral to how Ackroyd & Harvey develop ideas. To make the photographic content for rīvus, the artists worked with Uncle Charles ‘Chicka’ Madden, a widely respected Gadigal Elder, and his grand-daughter Lille Madden, First Nations director at Groundswell, a giving platform for climate action, and activist with Indigenous youth climate network Seed Mob.