She nodded in return. "Aphids are insects that feed on the sap of plants. They must have gotten in at some point in the fall... I found a few plants that were withered up because of them..."

Erika's frown deepened. The discovery of the ruined foliage had not been a pleasing time. "They're sort of a menace..." She motioned towards the puddle. "That sap would be their excrement."