This is a Rose Hooktip, or Oreta rosea. This specimen was found at Adam's house on June 16.

The Rose Hooktip can vary a lot in color, from all yellow to a dull pinkish-brown. This one is the intermediate form.

Rose Hooktips can measure from 2.5 to 3.4 cm. Their caterpillars feed on birches and vibernums.