Do I have to check my greens if I will blend them in a high powered blender?
Yes you should check the greens even if you are going to blend them. The reason is the following. The insects that are in the greens, although they are definitely the minority in comparison to the greens, still since they are whole they are considered prominent, and are not botil to the greens. If they would be chopped up, and no longer whole indeed they would be considered botil and nullified. This applies in retrospect, meaning that the items were already mixed together and the person didn’t do anything to cause the forbidden food to become nullified, however we are not do any action to cause the forbidden food to become nullified. This is called “ain mevatlin issur lichtchila”- we are not allowed to go and nullify something. Therefore by blending the greens were nullifying the forbidden food. This would apply to greens, since they are considered “muchzak b’tolaim”. However it would be permitted to blend vegetables that have only a small chance that they contain insects.