What do aphids look like?
Many have a pear-shaped body and a pair of small tubes, called cornicles, near the rear. Colors vary, and some adults have wings.
Why are leaves sticky near aphids?
Many aphids excrete honeydew, a sugary liquid. Sticky leaves can be a clue, but other sap-feeding insects also produce it.
What eats aphids?
Natural enemies include lady beetles and other predators. Look at the whole plant community rather than just one insect.
Try one observation
Photograph a small section of stem on two different days. Compare the visible colony and note other insects nearby.
Observe without handling or collecting. These clues are a starting point, not a confirmed identification.