I found this story on @HistoryWeird's blog here.The original source was The Washington Times, May 7th, 1905.
"In May 1905 an unnamed woman from southern Ohio wrote to the state’s governor, Myron T. Herrick, requesting 'permission to wear trousers'. The woman was single and lived alone so had no father or husband she could ask:
'"As reason for the request, she says she is forced to work out of doors in the management of a farm and male attire would be much more convenient for her than petticoats.
"'Press reports suggest that the governor replied, telling the woman that he could not grant permission for her to wear trousers – however he intended to consult the attorney general, with a view to forming 'an amendment to the laws to suit such a case'."