They don’t have mumps.
These tree-climbing rodents have mouthfuls of acorns.
Just a few chipmunks were systematically knocking acorns loose from treetops in Cary's Hoffman Park, causing them to fall like rain.
Chipmunks stationed on the ground were scooping up the fallen acorns into their mouths and running off with them into the woods.
Hundreds and hundreds of acorns from bur oak trees were strewn across a bike path on the east end of the park.
Residents are encouraged to collect pristine acorns and donate them to the Land Conservancy, to help with restoration of oak trees in McHenry County.
The Land Conservancy delivers donated acorns to Glacier Oaks Nursery in Harvard, Perrone said, where they are planted. They grow to become saplings, at which time they are replanted at a permanent location.
"The Acorn Roundup is a great way to get your kids, friends, neighbors or students involved in a worthwhile project," Perrone said.
Oak trees have been threatened by development, agriculture, invasive plant species and infestation of insects such as gypsy moths.
Prized trees in Hoffman Park include bur oak and shagbark hickory, said Ben Rea, superintendent of park maintenance for the Cary Park District.
There was no need to spray for gypsy moths this year, Rea added, but the Park District is monitoring the area closely. A program is under way to remove invasive species such as buckthorn and honeysuckle, which have been choking out the native oaks and hickories.
About one-third of McHenry County had oak-hickory woodlands in the 1830s, according to The Land Conservancy’s website. Today less than 5 percent of the county has oak woods — an 87-percent loss.
Choosing the right acorns
Acorns are ripe when their caps are easily removed without damaging the nut. Select the largest acorns from the healthiest-looking oaks, only those without cracks, holes or those that feel hollow.
Acorns, separated by species, can be dropped off at the Nature Conservancy office in the white farmhouse at 4622 Dean St., Woodstock, just north of Route 176.
Hours are 9 a.m. to 4:30 p.m. After hours, leave the acorns in a container at the door.