Examinations for the license shall be held by the board at least once each year. The board shall adopt rules and regulations covering the subjects and scope of the examinations, shall publish appropriate announcements and shall conduct the examinations at the times designated. Except as hereinafter provided in this chapter to the contrary, every applicant for licensing as a landscape architect shall be required, in addition to all other requirements, to establish by a board approved examination, which may be digital, his or her competence to plan, design, specify, and supervise the installation of landscape projects. Each board approved examination may be supplemented by such oral examinations as the board shall determine.