Curculio glandium Marsham (Coleoptera: Curculionidae) is a serious pest of oak trees in the Zagros Mountains, Iran. In this study, geo-statistical methods were used to simulate spatial distribution models for optimal management. The area of this strait is about 850 hectares; for this study, due to regional conditions, nearly 370 ha were examined. The desired area (Dalab Strait in Ilam province, Iran) was divided into six geographical height classes. For each class, an area of about 60 ha was selected, with 30 trees, and the latitude and longitude were determined. Monthly sampling was conducted on four oak fruits as the sampling unit in 2022 and 2023. In the laboratory, the number of oak fruits infected with the pest was counted. Data were normalized using one of the appropriate data transformation methods (logarithmic or Box-Cox Transformation), the cross-validation method was used to evaluate the efficiency of interpolation methods. The Root Mean Square Error (RMSE) was used to assess the models; the data were analyzed using GS+ version 5.1 software. The results showed that, in the survey of the spatial distribution of oaks infected with C. glandium, after fitting the data from 12 sampling stages, nine cases were consistent with the spherical model and three with the exponential model. The degree of spatial dependence (C0/C0+C) varied from 0.501 to 0.981 in 2022 and from 0.501 to 0.973 in 2023. In addition, in both years under study, the highest pest density was observed at an altitude of 1540-1600 meters above sea level. According to the maps, population density was higher in the southern location than in other locations, and the northern location had the lowest density. The results of this study showed that using geostatistics enables successful sampling for forest pests, especially the acorn weevil. In the development of pest management systems, early warning and tracking programs are very important. Managing the pest's special place is an effective way to achieve the control operation. The results of this study can be used for optimal monitoring and control of the acorn weevil in oak forests.
