Although a specialty within landscape design or landscape architecture, golf course architecture is considered a separate field of study. Some golf course architects become celebrities in their own right, such as Robert Trent Jones, Jr. ; others are professional golfers of high standing and demonstrated appreciation for golf course composition, such as Jack Nicklaus. The field is partially represented by the American Society of Golf Course Architects, the European Institute of Golf Course Architects, and the Society of Australian Golf Course Architects, although many of the finest golf course architects in the world choose not to become members of any such group, as associations of architects are not government-sanctioned licensing bodies, but private groups. While golf courses often follow the original landscape, some modification is unavoidable. This is increasingly the case as new courses are more likely to be sited on less optimal land. Bunkers and sand traps are almost always artificial, although other hazards may be natural.