The board shall investigate the allegations contained in any application for licensure under this act in order to determine the truth of the allegations and to determine the competency of any person applying for licensure to assume responsible charge of the work involved in the practice of landscape architecture, such competency to be determined by the grade and character of the landscape architecture work actually performed. Landscape architecture work performed under the supervision of a registered landscape architect shall be given full credit. Whenever the board determines otherwise than by examination that an applicant has not produced sufficient evidence to show that he is competent to be placed in responsible charge and shall refuse to examine or to license such applicant, it shall set forth in writing its findings and the reasons for its conclusions and furnish a copy thereof to the applicant.