Deer Ticks and Lyme Disease: Another Reason to Remove Invasive Shrubs
Over the last 6 months, I've had 3 friends in McHenry County diagnosed with Lyme disease as a result of being exposed to deer ticks, or  Ixodes scapularis. When I ran across this article from University of Connecticut about the links between the invasive shrub Japanese Barberry and Lyme disease, it really made sense, and I started to wonder if the situation applied to other non-native trees and shrubs like common buckthorn (Rhamnus cathartica). 

The Basics:  Deer ticks become infected with the Lyme bacteria (one example is Borrelia burgdorferi). How? Deer tick larva (left in picture) hanging out in the leaf litter on the forest floor feed on a small animal infected with Lyme, such as a white-footed mouse, chipmunk, or even a bird. The deer tick larva is now most likely infected with the Lyme bacteria. One they become a deer tick "nymph" (2nd from the left in picture) they look for another animal to feed on, which could be a human. They are very tiny and can pass the Lyme bacteria on to their host. Most Lyme infections in humans are believed to result from deer tick nymphs since their tiny size makes them so difficult to detect. Feeling itchy yet? Nymphs become larger adult ticks and feed on white-tailed deer and other larger hosts, including our pets and us. For more info, University of Rhode Island has one of the best tick information sites that I've found.

Connection to Invasive Brush: Back in 2012, researchers at University of Connecticut found a link between Japanese barberry (Berberis thunbergii), a non-native invasive shrub, and Lyme-infected deer ticks. Why? They believe it has to do with barberry providing a sheltered, humid environment that favor small rodents (likely carrier of Lyme bacteria), who then pass the infection on to humans as described in the above paragraph. Japanese barberry is a very common non-native shrub used in landscaping and has escaped into natural areas in many areas of the country, including here in McHenry County. Click here for information on how to identify Japanese barberry, seen in the picture below. In the UConn study, they found 120 infected ticks/acre in areas infested with barberry as opposed to 10 infected ticks/acre in areas with no barberry. And yes, recent research suggests that other non-native species such as common buckthorn can also be contributing to the rise in Lyme-infected ticks.

What Can You Do? Late fall and winter are ideal times to eradicate non-native trees and shrubs, whether it's through fire, herbicide, or mechanical control. Review last December's Conservation@Home newsletter on herbicide control and weed wrench options. The University of Connecticut article also discusses fire as a control method with a propane torch, widely available at any home improvement store (I bought one at Home Depot). TLC also offers classes on prescribed burning in the early spring, so watch the newsletter for that information. Buckthorn baggies are another herbicide-free method of control to check out. 


New! Photo Contest Category for C@H Properties
Are you an amateur photographer interested in taking pictures of your Conservation@Home certified property? We've added a special category for you in the 2017 Art of the Land photo contest! Click here for more information and to apply.
Conservation@Home Featured Property: Anne Basten


Anne Basten lives on a 2/3-acre C@H certified property in McHenry near Moraine Hills State Park. Over the last 35 years, she has been incorporating many sustainable elements into her property, from solar panels to easily incorporated paths of gravel under her gutters, draining her stormwater runoff into areas covered in native plants. She loves the wildlife she sees, from wood ducks using the nest boxes to bats and foxes as well. She advises those just starting to start small and be patient, enjoying the spreading of native plants each year and the discoveries that come along with it. Thanks for your participation and contributions to the ecological health of McHenry County, Anne!
The Land Conservancy of McHenry County | smichehl@conservemc.org |
815-337-9502 | www.ConserveMC.org