Many of our garden plants have "perfect" unblemished leaves lacking any evidence of nibbles taken by hungry herbivores, or dwelling places of leaf miners and other native insects. This artificial state of perfection is because many of our garden plants are from other continents and our native insects have zero chance of eking out a living from their foliage. But native plants have co-evolved with a diverse community of insects that live in and on them and in turn form essential links in the food web that feeds native birds and mammals. Hackberry nipple galls are formed by tiny insects that emerge as adults in fall and are valuable foodstuff for migrating birds. And the hackberry trees do not seem even slightly the worse for the wear.
