The pollen sacs, if any, that you might find will not be as prolific as a true male plant and thus will not release as much pollen. This will not ruin your crop. Your plants that happen to get pollinated will still produce CBD. If you are growing for smokable flower, you should try hard to catch any pollen sacs to avoid any seed in your flower. When you notice white pistils forming on the plants (flower initiation), you need to then begin to look for pollen sacs. There is no need to constantly walk your fields looking for pollen sacs early in the season.