A landscape architect is someone who practices landscape architecture. Regulations of the profession vary by country and state. The terminology has evolved to include those once known as landscape gardeners, landscape designers, architects, surveyors or civil engineers, particularly those from the 19th century who practised before the term "landscape architect" was coined. Landscape architecture was also differentiated as a profession in the United States earlier than in other parts of the world so this ambiguity has persisted to the present day; in much of Europe, for example, landscape architecture is not a distinct profession but there are many significant historical and contemporary examples of "landscape architectural design" projects. Though their influence on landscape architecture may be great, this list precludes gardeners, botanists, writers, theoreticians, ecologists, artists, and others who did not practice landscape design at a site scale and were not trained as a historical 'landscape gardener' or contemporary 'landscape architect.'