While wasps are active all summer long, in late summer they become more aggressive as they prepare the hive for winter. Wasps can’t forage for food during the winter. In most species, workers and soldiers die off leaving the queen alone in the hive. This means that she will need to have all the energy she needs not only to survive the winter, but also to start the new hive next spring. This takes a lot of energy. Wasps gather this from sugar. In the wild, this sugar comes from natural sources like rotting fruit and nectar, but wasps can also collect it from human food sources as well. This is what attracts them to human activities.