WNPR

Is This Invasive Shrub A Deer Tick Haven?

Oct 19, 2017

What started as one scientist's hunch turned into a decade of research, which now claims a positive link between an invasive shrub called Japanese barberry and deer ticks.

Japanese barberry came to the Northeast in the late-1800s. At first it was a landscape plant, but it soon escaped cultivation and landed in many wild parts of Connecticut.

It’s thorny with red fruit. And Scott Williams, a scientist with the Connecticut Agricultural Experiment Station, said it's hard to kill.

“It can really take over and create these massive infestations that, ultimately, retain humidity throughout the day,which makes a great microclimate for ticks to survive and thrive under,” ” Williams said.

Years ago he said he was looking at ways to control the plant.

“While we were doing it, we noticed we were getting a lot of deer ticks on our person,” Williams said.

So he had a thought: Is barberry -- this waist-high shrub -- a favored spot for deer ticks?

To find out, he identified six locations under a mature forest canopy. Some spots had barberry. Others didn’t. And in some places, the barberry was managed.

Then his team went out and counted ticks.  

“Ten years of wading through barberry and playing with ticks is kind of enough for my crew and I,” Williams said.

What that decade of data told Williams was this: managing barberry meant fewer ticks. Especially those causing Lyme disease. The research was published in the journal Environmental Entomology.

Williams said this year has been a strong one for Connecticut ticks. Due to a mild winter and lots of acorns. High acorn numbers mean more rodents, and when ticks feed on them, they can contract Lyme disease agents, which later get passed to humans.

Williams said he hopes calling attention to another causal agent for ticks in Connecticut doesn’t drive people inside. Instead, he hopes it makes them more savvy outdoors.

"We’re trying to make people aware of these associations,” Williams said. “So they can enjoy being outside while being educated on how to take care of themselves and the forests in Connecticut.”