petiole removal from a binary leaf image

I am trying to remove the petiole part from the image of the leaf. It’s a binary image. I have tried using imopen(matlab) with rectangular structuring element. That is working but is also affecting the remaining part of

image. I have also tried making those particular pixels (rows and columns) zero in the binary image. But for different leaf images the petiole length changes. Also the leaf in the image could be at different orientations. I have to keep changing the row and column values depending on different images. Is there any generalized way of doing it that can be applied to different images?