Iowa Code § 544B.2: License required.

A person shall not engage in the practice of landscape architecture, or use the title “landscape architect”, “professional landscape architect”, “landscape architecture designer”, or use other titles or words, letters, figures, signs, cards, advertisements, symbols, or other devices to represent that the person or a business associated with the person is authorized to practice landscape architecture, without first obtaining a license as a professional landscape architect from the board pursuant to this chapter. Every holder of a license as a professional landscape architect shall display it in a conspicuous place in the holder’s principal office.