William Alexander Jenyns Boyd was the younger son of Charles Boyd, an English army officer, and his French wife Mary Vachell. He was educated at a number of schools in England and Europe, including the Lycee de Versailles, near Paris. On leaving school, instead of taking up a career in the army as had been anticipated, Boyd spent a brief period working on American sailing ships. He then migrated to Queensland, arriving at Brisbane on the Saldanha in January 1862.
Within about a year of his arrival, Boyd took up farming at Oxley Creek, where he was to experiment with sugar growing. Then, in 1867 he was appointed head teacher at the newly established Oxley Creek National School, where he was assisted by his wife. In late 1871, he moved to Pimpama, where he ran a sugar plantation, and also conducted a small preparatory school. However, his sugar growing venture proved a failure, and he became insolvent. In 1873, Boyd then moved to Townsville, where he taught at the National School, later becoming headmaster, and also District Inspector of Schools. In 1875 he purchased the Cleveland Bay Express, which he briefly owned and edited, before returning to Brisbane in early 1876 to join the Queenslander as its agricultural editor. Boyd left the Queenslander in mid 1877 to start 'Eton', a preparatory school for boys, which he ran at Milton and then Nundah until mid 1888. From mid 1888 through to early 1890 he was headmaster at Toowoomba Grammar School, before resigning in controversial circumstances. He then returned to Brisbane where he revived 'Eton' school from mid 1890 until it finally closed in mid 1893. In 1895-1896 he helped fill the headmaster's position at Ipswich Boys' Grammar School, whilst the incumbent was on leave. He then joined the Queensland Department of Agriculture, where he was appointed editor of the newly established Queensland Agricultural Journal, a position which he held from 1897 until his retirement in 1921. In addition to his other interests, during the 1880s and 1890s, Boyd also served in the Brisbane Volunteer Artillery, where he attained the rank of Major. Boyd was a cousin of the English author Horace Annesley Vachell (1861-1955).