Shortly after the start of the war, Confederate Surgeon General Samuel Preston Moore instructed Surgeon (Major) Francis Perye Porcher to prepare a "treatise on the resources of Southern fields and forests" regarding the "medicinal, economical and useful properties of the trees, plants and shrubs" found in the Confederacy. Moore realized from the beginning of the war that medical supplies would be in short supply; this became ever more critical when medical and surgical appliances were named "contraband of war" by the Union government. So important was the task of developing indigenous botanical substitutes for drugs and medicines that he temporarily relieved Porcher of his duties as surgeon to the Holcombe Legion. Porcher was the obvious choice for this task having already written two medico-botanical texts: one of the flora of South Carolina and the other about the botanical properties of plants of the United States. His new book, Resources of the Southern Fields and Forests, Medical, Economic and Agricultural, is credited with saving "the Confederacy for two years"