Biology teachers are fully aware that plant diseases are but one of many biological phenomena, but their young charges often enter the classroom without ever having thought that plants have diseases just as do humans, livestock, and pets. Trees do not die of old age. They succumb to abuse and disease. The farmer does many things, such as rotating crops and using special varieties, not by chance but because he must do so to escape or prevent disease outbreaks in his crops. The dead spot in the lawn, the brown rot on the peach in the refrigerator, and prematurely fallen or mildewed leaves are aspects of disease that may be used to fire the imagination of youth with the importance of microscopic forms of life. It would be naive to suggest that any substantial amount of the voluminous knowledge on the 100,000 plant diseases present in North America could be presented in a general biology curriculum. Teachers, of course, must select carefully the subject matter that communicates clearly the facts and concepts concerning such basic topics as the diversity of the plant and animal worlds, and the fundamental facts of physiology, disease, reproduction, heredity, and evolution of species and societies. On the other hand, the teacher has a great responsibility to make students aware of the phenomenon of disease in plants. Remember that this may very well be the only time that three-fourths of them will be exposed to authoritative knowledge on the subject. Few of those that go on even for advanced training in the universities will be exposed to courses in plant diseases; they will become lawyers, housewives, captains of industry, or professors of the humanities with complete unawareness of one of the important natural phenomena. Many of them some day will become the suburbanites or home lovers who will try to cultivate ornamentals and vegetables in their gardens and will wonder why their plants languish and die in spite of the best care and loving attention. The teacher finds himself on the horns of the usual dilemma in deciding how much material he should present in a biology class. How much should be devoted to broad fundamentals? And how much should be devoted to specific detailed information? There is possible, however, a reasonable compromise. Aspects of plant pathology may be utilized to illustrate many basic concepts of general biology, thereby presenting factual information of the science of plant pathology and at the same time enriching overall the subject matter offered.