A casual walk through an Ithaca cemetery led to the discovery of a gigantic hidden bee population — roughly 5.5 million ground-nesting bees packed beneath the soil. Scientists believe it may be one of the largest bee aggregations ever documented and say the insects are crucial pollinators for apple orchards and other crops. The bees have likely lived there for more than 100 years, thriving in the cemetery’s undisturbed sandy soil.