Aphids are not easily deterred. They secrete a sticky substance from their abdomen that detracts predators and they reproduce madly. One count demonstrated that they can reach upwards of a million per acre. It’s not uncommon to see a variety of ages in a colony. If left to reproduce with no predators, pathogens, parasites, etc., a single aphid could produce over 600 billion offspring in one season!! Thank goodness for our aphid predators!
Aphids overwinter as eggs. If you look near the buds of trees, you might see those little black eggs. Starting with trees in the winter and moving to plants in the spring & summer, it’s easy to see why these bugs are so prevalent.