Section 102. Examinations for registration as a landscape architect shall be held by the board at least one each year, provided that applications shall have been receiving during the time announced. 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, every applicant for registration as a landscape architect shall be required, in addition to all other requirements, to establish, by written examination, his competency to plan, design, specify and supervise the installation of landscape projects. Each written examination may be supplemented by such oral examinations as the board shall determine.