With the rapid development of remote sensing technology, crop classification and health detection based on deep learning have gradually become a research hotspot. However, the existing target detection methods show poor performance when dealing with small targets in remote sensing images, especially in the case of complex background and image mixing, which is difficult to meet the practical application requirementsite. To address this problem, a novel target detection model YOLO-RS is proposed in this paper. The model is based on the latest Yolov11 which significantly enhances the detection of small targets by introducing the Context Anchor Attention (CAA) mechanism and an efficient multi-field multi-scale feature fusion network. YOLO-RS adopts a bidirectional feature fusion strategy in the feature fusion process, which effectively enhances the model's performance in the detection of small targets. Small target detection. Meanwhile, the ACmix module at the end of the model backbone network solves the category imbalance problem by adaptively adjusting the contrast and sample mixing, thus enhancing the detection accuracy in complex scenes. In the experiments on the PDT remote sensing crop health detection dataset and the CWC crop classification dataset, YOLO-RS improves both the recall and the mean average precision (mAP) by about 2-3\% or so compared with the existing state-of-the-art methods, while the F1-score is also significantly improved. Moreover, the computational complexity of the model only increases by about 5.2 GFLOPs, indicating its significant advantages in both performance and efficiency. The experimental results validate the effectiveness and application potential of YOLO-RS in the task of detecting small targets in remote sensing images.