UMass Extension Weed Herbarium

A Big Year for Ticks

A questing adult deer tick

As anyone spending time outdoors this past year will tell you, it’s been a really big year for ticks.  The UMass Extension Tick Assessment Laboratory had twice as many ticks submitted to it as in previous years.  We believe that the onslaught was subsided.  Tick nymph and adult numbers are regulated by mouse abundance of the previous year (ticks have a two year life), and mouse abundance is influenced by acorn production. This past year’s tick spike followed (as predicted) the acorn mast from two years before.  Following that year, there was a “mast failure” (no acorns) which should result in many fewer ticks. Tick submissions to the lab seem to be bearing this out.

Fall is the time that adult deer ticks appear.  Deer ticks overwinter as adults and can attach to hosts at anytime that they are not covered with snow.  Frosts or cold weather do not kill ticks.  About 30% of the ticks tested at the lab carry the pathogen for Lyme disease. In addition about 10% carry a related bacterium called Anaplasma and 5% carry a malaria-like pathogen called Babesia.  The UMass Extension Tick Assessment Laboratory can determine whether or not a tick carries these pathogens.

Information on submitting a tick for diagnosis can be found at