Between 1841 and 1845 he issued three exsiccata-like series, among them Mycologia Britannica or specimens of British fungi[1] and with William Baxter another exsiccata under the title Flora Thamnensis.
[2] In 1856 Ayres was appointed by Queen Victoria to superintendency of quarantine on Flat Island, Mauritius under governor Robert Townsend Farquhar.
[3] From 1856 to 1863 he traveled through Madagascar, the Seychelles, and the Mascarenes to develop this rich collection of Indian Ocean plant specimens.
In addition to collecting, Ayres catalogued and sketched the plants in the wild, as was common among nineteenth century naturalists.
Ayres' wife Harriet collected his written records and bequeathed them to the Royal Botanic Gardens, Kew.