@srbhdix 

Hi，
The basic camera's detection mechanism is based on image changes between different frames. The frame is one of the many still images which compose the complete moving picture. If there is a difference between the frames, the camera will recognize it as a motion detected.
The tree's movement and natural motion will cause a significant change in the image, therefore this kind of detection cannot be avoided.

You can refer to the following instructions to change the settings on the camera and check if it helps.
How to reduce motion detections from rain, snow, insects, etc?
 

Best Regards