Beech Blight Aphids tend to be found in clusters and may at first be overlooked as a fungus. Like other aphids, they use their mouth parts to drain their host plant of its juices. They then produce a sticky, sweet substance called "honeydew" from the plant juices once they eliminate it. Honeydew is an attractive food source for ants and, therefore, it is likely to find ants in the vicinity of aphids in order to harvest the sap-like excretion.
Though the Beech Blight Aphid is tiny compared to other insects, in large numbers, they have the potential to devastate plant populations. Aphids are rapid reproducers and can dry out and kill large swaths of trees if left unchecked. Controlling their population is done naturally by the wasps and beetles that eat them. Chemical sprays are also available that specialize in killing aphids of many species though it is usually reserved for smaller house or garden plants.