 Macleay corresponded with and sent indigenous plant specimens to Kew, donated exotic plants to the Sydney Botanic Gardens, supplied trees to nurseryman Thomas Shepherd, exchanged plants with William Macarthur at Camden Park, encouraged local naturalists, and promoted exploration.As a member of numerous public and charitable committees, he exerted considerable influence in the establishment of the Australian Museum, the Australian Subscription Library, and more particularly on policy at the Botanic Gardens.Macleay, who had served diligently as Colonial Secretary, was ousted from office by Governor Bourke in 1837.