[1] She wrote 24 books covering topics ranging from her life as a settler in Ontario to natural history, especially botany.

[1] Through her writing, she related the colonial experience and described the natural environment of Upper Canada for English readers.

[1] Traill's father retired from his position as manager of the Greenland Docks on the River Thames and moved the family to the countryside in Suffolk, shortly after her birth.

[6] After Thomas Strickland died in 1818, Catharine and her sisters turned to writing and editorial work as the main source of family income.

[5] Her early works, such as Disobedience, or Mind What Mama Says (1819) and "Happy Because Good", were written for children, and often dwell on the benefits of obedience to one's parents.

In 1832, she married Lieutenant Thomas Traill, a retired officer of the Napoleonic Wars and a friend of her sister's husband, John Moodie, despite objections from her family (aside from Susanna).

She describes everyday life in the community, the relationship between Canadians, Americans, and Indigenous peoples, the climate, and local flora and fauna.

While Susanna was more concerned with the differences between rural and urban life, Catharine spent her years in Belleville writing about the natural environment.

[10] She received a grant c. 1899 from the Royal Bounty Fund, which was supplemented by a subscription from her friends in Canada, headed by Sir Sandford Fleming.