Heather Ackroyd and Dan Harvey (b. 1959/1959 England) have been collaborating since 1990 exploring the themes of growth, transformation and decay through a variety of media including sculpture, photography, architecture and landscape design. Their work juxtaposes nature and structure, control and randomness to reveal a time-based practice with an intrinsic bias towards process and event. Over the last few years Ackroyd & Harvey have made a series of expeditions to the High Arctic with the Cape Farewell project, looking at the effects of global warming on the ecosystem.

Ackroyd & Harvey are acclaimed for their experimentation with the light sensitivity of seedling grass and its ability to record complex photographic images. Their early work with grass brought them to work with scientists at the Institute of Grassland and Environmental Research in Wales. Their collective research lead to remarkable results for both the artists and the scientific community. The artists have also used grass to create monumental works such as FlyTower (2007), whereby they grew the entire north and west face of the of London's National Theatre landmark building with seedling grass.

Ackroyd & Harvey have exhibited widely including at Mostra SESC Des Artes, Sao Paulo, Miraikan Museum, Japan, Liverpool Art Biennale, Natural History Museum London, Sculpture Quadrennial, Riga, Chicago Public Art Program, and the V&A Museum London. They been recipients of numerous awards including two RSA Art For Architecture awards, Wellcome Sci-Art, NESTA Pioneering Award and the L'Oreal Art & Science of Colour Grand Prize. They live and work in Surrey, England.

Many hours of Ackroyd & Harvey's March 2001 residency were spent studying the collection, documenting, and finding source material in preparation for their exhibition in October. They extensively photographed the galleries and researched the early manuscript and textiles collection. Among the objects that drew the artists' attention were the Crawford Bookcase in the Blue Room, containing photographs and correspondence by Marion Crawford, William James, Thomas Russell Sullivan, Henry James, as well as the collected manuscripts of Henry Wadsworth Longfellow, William Cullen Bryant and a plaster cast of William Greenleaf Whittier's hand. Other works that the artists incorporated into the show were two Spanish iron clad doors from the 12th century, an excerpted text taken from Dante Alighieri's Canto IV, Comedia del Divino Poeta Fiorentino Dante (1481), in the Long Gallery, a terracotta Bust of Saint John the Baptist ca. 1480 from the Dutch Room, and the Bust of a Woman, a late 19th century sculpture from the Gothic Room.

For the month of October, Ackroyd & Harvey turned the Special Exhibition Gallery into their studio and darkroom. They built, seeded, and exposed, nine canvases which grew with the help of daily care and watering. Their process was recorded by filmmaker Mark Lipman and made into a short film. In addition, a CD-Rom called Presence: The Ephemeral in Focus was created in collaboration with Isabel Mierelles and Fenya Su from the Dynamic Media Institute at Massachusetts College of Art. This contained Lipman's footage of the germination process, interviews, excerpts from the artists' work with scientists, and examples of Ackroyd and Harvey's previous works. The museum was awarded Honorable Mention by the American Association of Museums for this CD-Rom in 2004.

In conjunction with the exhibition, Presence, the artists spoke about their fascinating work with photosynthesis and genetic research to create sustainable grass photographs. The desire to arrest the ephemeral grass image had brought them together with scientists at the Institute of Grassland and Environmental Research (IGER), whose pioneering research led to the development of a "stay-green" grass. Their five-year collaboration produced highly effective results and is a prime example of how art and science work together. The artists were joined by curator Pieranna Cavalchini, British scientists Professor Howard Thomas and Dr. Helen Ougham from IGER (via conference call), and Carole Kismaric, co-curator of Paradise Now, a 2000 exhibition on contemporary artists exploring genetics.

While preparing for their exhibition, Ackroyd & Harvey worked with a class of fifth graders from the Farragut School. The students learned how to make their own art by using the process of photosynthesis. During a series of visits in both the museum and the classroom, the artists described their technique of fixing photographic images in growing grass. The students then made stencils based on drawings they had made of objects and architectural elements in the Gothic Room. Next, the artists assisted them in growing their own grass images using the stencils made at the museum. A week after the images were planted, they were green and ready for exhibition in the school hallway.

In 2006, Dan Harvey was invited to talk about their trip and project in the Arctic in conjunction with Henrik Håkansson's exhibition. He also lead a crystal growing activity during Neighborhood Nights. Five years later, Harvey returned for two weeks to re-grow Script, a work from their 2001 exhibition. The piece was installed January 2012 in Points of View, an inaugural exhibition celebrating the opening of the museum's new wing and the twentieth anniversary of the museum's Artist-in-Residence program.

Presence: The Ephemeral in Focus CD-Rom