Why Are Yellowjacket Numbers Rising Here?

No, killer bees have not have made their way north into Lancaster County. But, ground nests of native Yellowjacket wasps have appeared in recent weeks in inordinate numbers, cancelling a popular trail run, closing a nature preserve and touching off daily frantic calls for help from frantic homeowners to area pet control companies.  The most reeent victim of the swarms was the cancellation of the 16th annual KTA trail Challenge scheduled for August 28 in the River Hills of southern Lancaster County.  The rugged 25-kilometer event by the Keystone Trails Association attracts trail runners and extreme hikers from around the state and beyond.  This year, nearly 20 had planned on navigating the step climbs, hollows and scenic Susquehanna River views from the Conestoga Trail.  About 70 volunteers were to provide safety measures in the area with little cellphone service.  But, the major fund-raising event for the statewide trails group was canceled after runners training for the run, KTA staff making advance preparations and members of the Lancaster Hiking Club doing trail maintenance, all encountered  yellow jacket nests either on or beside the course.  One woman doing an advance run with a friend was stung and injured herself in a fall while fleeing.  Two KTA staffers checking out the course "said when they got out of their cars they could actually hear the buzzing in the forest," reported Kate Prissy, KTA's manager of events and programs.  Then KTA learned that the Lancaster Conservancy had temporarily closed its popular Kelly's Run Nature Preserve, which the Conestoga Trail runs through, after conservancy staff located 15 Yellowjacket nests.  "That's unheard of," said Keith Williams, the conservancy's vice president of engagement and education.  "In years past, we easily managed this problem with signage and education.  "They're just doing their job and protecting their nest.  The community wants to go out to our preserves, and we need to have the right balance between protecting nature and protecting our community."  Still, KTA hoped to pull off the run by putting up caution signs near nests.  But then a staffer found a cloud of Yellowjackets hovering just above the trail with no way of going around them besides the trail was wedged between steep hillsides.  "That was the deciding factor." Prisby said.  "We just didn't feel it would be wise to have people coming and not knowing what they would be running through.  And it would not be fair to the medical teams."  So what are these insects and why are they exploding in numbers this fall?  Yellowjackets are small wasps with yellow and black bands that many Lancaster County residents encounter this time of the year when they fly purposefully to your soft drink or plate of fruit.  Like all native insects, they are beneficial and reduce populations of insect pests such as earwigs and pollinate plants.  There are more around in the fall because the colony has grown all summer and with food sources drying up, leaving a crowded mass of hungry, agitated bees that fiercely defend nests.  It's said even ground vibrations from someone walking nearby can rigger attacks.  Unlike honey bees that sting only once with a barbed stinger, yellowjackets can zap you with their straight stinger several times.  Worse, when threatened, they release an arm pheromone chemical that puts others in attack mode.  There are records of people being pursued and stung 100 times or more.  The sting of a Yellowjacket is no picnic.  According to the Schmidt Sting Pain Index, the pain from Yellowjackets is like 'W.C. Fields extinguishing a cigar on your tongue." For those allergic to bee stings, medical treatment should be immediate.  One recommended ointment of stings: good old-fashioned mud!  The explosion of yellow-jacket numbers has been noticed across the country.  Calls for help with getting rid of Yellowjacket nests are now coming in every day.  Yellowjackets will go dormant after a good freeze.  Hope for cold weather...and soon!  It was another extraordinary day in the life of an ordinary guy.