A method for the control of harmful organisms in a field in which crop plants are grown, wherein the method comprises the following steps: creation of a first infestation map, wherein in the first infestation map subareas in the field are indicated in which an infestation with harmful organisms has been observed in a past cultivation period, and creation of a second infestation map, wherein in the second infestation map subareas in the field are indicated in which an infestation with harmful organisms has been observed in the current cultivation period, and subarea-specific prediction of the infestation risk to the crop plants with harmful organisms for the current cultivation period, wherein the prediction is made - on the basis of the first infestation map and on the basis of the second infestation map and - on the basis of subarea-specific information on the state of development of the crop plants and/or on the basis of subarea-specific environmental factors and - on the basis of weather information, and creation of a treatment map, wherein in the treatment map it is stated which subareas of the field are to be treated, in order to prevent the dispersal of harmful organisms and/or to control harmful organisms, wherein the treatment map - is created on the basis of the prediction of the infestation risk for the current cultivation period, and - is created and/or adapted on the basis of the conditions predicted for the time of the planned treatment with regard to weather, and/or development state of the crop plant and/or environmental factors, and treatment of subareas of the field in accordance with the treatment map, wherein the prediction in step is made by modeling of the dispersal of harmful organisms by means of a rule- or process-based model and the following parameters influence the modeling: a) weather, b) soil, c) crop plant, d) cultivation measures, e) development state of the crop plant, f) current infestation, g) geography. creation of a first infestation map, wherein in the first infestation map subareas in the field are indicated in which an infestation with harmful organisms has been observed in a past cultivation period, and creation of a second infestation map, wherein in the second infestation map subareas in the field are indicated in which an infestation with harmful organisms has been observed in the current cultivation period, and subarea-specific prediction of the infestation risk to the crop plants with harmful organisms for the current cultivation period, wherein the prediction is made - on the basis of the first infestation map and on the basis of the second infestation map and - on the basis of subarea-specific information on the state of development of the crop plants and/or on the basis of subarea-specific environmental factors and - on the basis of weather information, and - on the basis of the first infestation map and on the basis of the second infestation map and - on the basis of subarea-specific information on the state of development of the crop plants and/or on the basis of subarea-specific environmental factors and - on the basis of weather information, and creation of a treatment map, wherein in the treatment map it is stated which subareas of the field are to be treated, in order to prevent the dispersal of harmful organisms and/or to control harmful organisms, wherein the treatment map - is created on the basis of the prediction of the infestation risk for the current cultivation period, and - is created and/or adapted on the basis of the conditions predicted for the time of the planned treatment with regard to weather, and/or development state of the crop plant and/or environmental factors, and - is created on the basis of the prediction of the infestation risk for the current cultivation period, and - is created and/or adapted on the basis of the conditions predicted for the time of the planned treatment with regard to weather, and/or development state of the crop plant and/or environmental factors, and treatment of subareas of the field in accordance with the treatment map, a) weather, b) soil, c) crop plant, d) cultivation measures, e) development state of the crop plant, f) current infestation, g) geography.