When fall arrives, the Black and Yellow Mud Dauber (Sceliphron caementarium) makes mud balls, hollows them out, and sticks them together with more mud. She packs each mud ball with spiders that she has paralyzed and lays one egg on one of them. She seals the mud ball and leaves it unprotected. When the larva hatches, it eats the spiders before making a cocoon in which it winters. It emerges from the mud ball in the spring as an adult. This mild mannered solitary wasp will let careful admirers observe it quite closely when partaking of the nectar of flowers, and it is unlikely to sting unless pestered.