Link Between Japanese Barberry and Lyme Disease

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edfrank
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Link Between Japanese Barberry and Lyme Disease

Post by edfrank » Fri Mar 22, 2013 9:11 am

Ed:

This is a recent research article about the relationship between Japanese barberry and Lyme disease. I wanted to pass this information along in hopes it might save someone in ENTS from getting Lyme.

Sincerely,

Russ Richardson

Subject: Native Plants and Wildlife Gardens - More Findings on the Link Between Japanese Barberry and Lyme Disease
Japanese Barberry infestation.  photo by Edward Forrest Frank
Japanese Barberry infestation. photo by Edward Forrest Frank

More Findings on the Link Between Japanese Barberry and Lyme Disease
by Debbie Roberts, Native P{lants and Wildlife Gardens
March 20, 2013.

http://nativeplantwildlifegarden.com/mo ... e-disease/

Recently, I attended a symposium where current research findings on the link between Japanese barberry (Berberis thunbergii) and Lyme disease http://gardenofpossibilities.com/2009/1 ... -barberry/ were presented. Over the past few years we’ve learned that this highly invasive non-native shrub is not only impacting our regional ecosystems, it’s also indirectly affecting our public health. While Japanese barberry is considered invasive in at least 20 states and the District of Columbia http://www.nps.gov/plants/alien/fact/beth1.htm , it is also still available for sale in many nurseries across the US. According to recent studies by scientists Jeffrey Ward and Scott Williams at the Connecticut Agriculture and Experiment Station (CAES) eliminating stands of Japanese barberry from forested areas can reduce the number of Lyme disease-infected ticks on the property by 80%.

continued at: http://nativeplantwildlifegarden.com/mo ... e-disease/
.
"I love science and it pains me to think that so many are terrified of the subject or feel that choosing science means you cannot also choose compassion, or the arts, or be awe by nature. Science is not meant to cure us of mystery, but to reinvent and revigorate it." by Robert M. Sapolsky

Joe

Re: Link Between Japanese Barberry and Lyme Disease

Post by Joe » Fri Mar 22, 2013 1:43 pm

"eliminating stands of Japanese barberry from forested areas can reduce the number of Lyme disease-infected ticks on the property by 80%"

I hope that's true but I suspect that's over optimistic.
Joe

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Rand
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Re: Link Between Japanese Barberry and Lyme Disease

Post by Rand » Fri Mar 22, 2013 8:19 pm

It seems that stands of Japanese barberry retain humidity. And ticks need an environment with about 80% humidity to actively feed, quest and reproduce. By measuring humidity levels above and at ground level under the barberry foliage, Ward and Williams found humidity levels under Japanese barberry dipped below 80% for only one hour per day. In open, sunny areas with no Japanese barberry, the exact opposite is true. The humidity levels rise to 80% for only one hour each day.
White-footed mice, a known apex host for Lyme disease also thrive under the canopy of Japanese barberry. The combination of mice and a tick population this is active almost all day long appears to be a potent mix that is leading to a public health epidemic in many states.
It sounds like any sufficiently thick/brushy growth would do this. I suppose invasive species are more likely to grow in this fashion, but it makes me wonder about native species too. Just stay out of brushy forests in general?

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DougBidlack
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Re: Link Between Japanese Barberry and Lyme Disease

Post by DougBidlack » Fri Mar 22, 2013 9:38 pm

I'm always bothered by people that take a little information and apply it incorrectly to serve their own interests. Ticks don't care about Japanese barberry one way or the other. They care about the same things as other animals: Do I have enough food and water? Do I have a safe place to hang out? Japanese barberry and lyme disease do well in disturbed habitats. Japanese barberry does not cause lyme disease, it simply likes the same environmental conditions and so it is more like a good indicator species. Without a disturbed habitat, high rodent and deer populations and a large human population living within this ecosystem you are going to have plenty of lyme disease with or without the Japanese barberry. It sounds like Japanese barberry is particularly good at keeping relative humidity high close to the ground, but if you rip it out something else will grow in its place and the ticks will adapt. I have no Japanese barberry in the forest behind my house but I have plenty of native shrubs, rodents and deer...oh, and tons of lyme disease in those little boogers!

I don't like Japanese barberry either but I think people do a great disservice by stretching a little bit of information way too far.

Doug

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edfrank
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Re: Link Between Japanese Barberry and Lyme Disease

Post by edfrank » Fri Mar 22, 2013 10:29 pm

My general observation would be that the other plants in these areas, even disturbed areas, do not seem to have the branch density of the barberry and might not be as ideal of a brooding site as are the barberry patches. So removal might decrease the numbers of ticks, but will not eliminate the problem. I would also agree as Doug cautioned, not to try to stretch the limited data too far.

Edward Forrest Frank
"I love science and it pains me to think that so many are terrified of the subject or feel that choosing science means you cannot also choose compassion, or the arts, or be awe by nature. Science is not meant to cure us of mystery, but to reinvent and revigorate it." by Robert M. Sapolsky

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DougBidlack
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Re: Link Between Japanese Barberry and Lyme Disease

Post by DougBidlack » Sat Mar 23, 2013 8:37 am

Ed,

yes, I'm sure that the structure of barberry is part of what makes it so ideal for the ticks but just as important is that deer don't like to feed on them. My point is that Japanese barberry isn't the root of the problem. If you want to reduce Lyme disease then convert the landscape to mature forest with little shrubbery and get the deer population to a much lower level while the forest matures. People don't want to hear this though.

Doug

Joe

Re: Link Between Japanese Barberry and Lyme Disease

Post by Joe » Sat Mar 23, 2013 8:48 am

DougBidlack wrote:Ed,

yes, I'm sure that the structure of barberry is part of what makes it so ideal for the ticks but just as important is that deer don't like to feed on them. My point is that Japanese barberry isn't the root of the problem. If you want to reduce Lyme disease then convert the landscape to mature forest with little shrubbery and get the deer population to a much lower level while the forest matures. People don't want to hear this though.

Doug
sounds right to me- however, we simply can't convert all the landscape to mature forest- the next best thing, for managed forests, is to cut lightly because doing so results in less brush - and it also results in less invasive species infestation.... but, people in the forestry world seldom listen to me, despite ranting about this and many other issues for the past 40 years...

I don't hunt and dislike guns of all sorts- but I don't mind if others hunt - for me, killing anything other than bugs is bad karma, but if others hunt, it's their karma and maybe they'll get some good karma if it results in less Lyme disease...

here in Mass., on the Quabbin watershed, that sends water to Boston, there is one 28 acre patch of solid Japanese barberry which I've seen- something they don't like to talk about- in their publications, instead, they brag about their awesome work....
Joe

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edfrank
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Re: Link Between Japanese Barberry and Lyme Disease

Post by edfrank » Sat Mar 23, 2013 9:02 am

Doug,

Of course mature forests with little underbrush and lower deer populations are better. But in many places we don't have that situation. If ripping pout the nasty barberry populations lowers the overall tick population, that is another reason to do so. On public land it might be the extra nudge needed for the park or land managers to take the step of ripping out the invasives and trying to do some ecological restoration.

Ed
"I love science and it pains me to think that so many are terrified of the subject or feel that choosing science means you cannot also choose compassion, or the arts, or be awe by nature. Science is not meant to cure us of mystery, but to reinvent and revigorate it." by Robert M. Sapolsky

Joe

Re: Link Between Japanese Barberry and Lyme Disease

Post by Joe » Sat Mar 23, 2013 9:24 am

On the Quabbin-- they can't use herbicides... they could rip out the plants, but then they'd have to find the money- of course they have lots of money but it gets misspent, so they claim they can't afford to.

Joe

Re: Link Between Japanese Barberry and Lyme Disease

Post by Joe » Sat Mar 23, 2013 9:27 am

Maybe we could do some genetic engineering on deer and other browsers so their favorite food would be invasives! (not likely of course, but you never know)

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