[APWG] Fw: [MPWG] Japanese stiltgrass disease update June 2 2010

[Patricia_DeAngelis at fws.gov]

I am responding to Russ Richardson's post and forwarding this message to 
APWG since it involves an invasive plant (Microstegium vimineum, Japanese 
stiltgrass; see the APWG fact sheet at: 
<http://www.nps.gov/plants/alien/fact/mivi1.htm>) that is being attacked 
by a fungus (apparently a Bipolaris species; see: 
<http://aggie-horticulture.tamu.edu/archives/parsons/turf/publications/Bipolaris.html>
)!!!! 

The fungus is as tenacious as the invasive plant (i.e., both can 
overwinter) and is taking a toll on the stiltgrass, by reducing its 
presence. The fungus also attacks other non-native warm season grasses 
(such as bentgrass) and native invasives (such as cheatgrass).  Too soon 
to tell what may come of this development. Will the fungus keep stiltgrass 
from coming back into previously infected areas? What effect will this 
fungus have on the other understory species, the natives (many of which 
are medicinal or otherwise harvest for their non-timber forest products)? 
I'm pretty sure I have seen it on black cohosh at the MPWG field sites in 
George Washington Jefferson National Forest - started seeing it maybe two 
years ago.

Sounds like that is just what Luke Flory, of Indiana University, is 
looking at.  Russ mentions an article in press (perhaps this one: 
Kleczewski, N. and S.L. Flory. 2010. Leaf blight disease on the invasive 
grass Microstegium vimineum (Japanese stiltgrass) caused by a Bipolaris 
sp. Plant Disease. In press. ).  According to the abstract (at: 
<http://www.lukeflory.com/publications>), "Disease reduced seed head 
production by 40% compared to controls."

-Patricia

Note: I removed Russ's pictures because the email was so large. I'm sure 
he'd be happy to send them to you if you contact him directly. 

Patricia S. De Angelis, Ph.D.
Botanist - Division of Scientific Authority
Chair - Plant Conservation Alliance - Medicinal Plant Working Group
US Fish & Wildlife Service
4401 N. Fairfax Dr., Suite 110
Arlington, VA  22203
703-358-1708 x1753
FAX: 703-358-2276

Promoting sustainable use and conservation of our native medicinal plants.
<www.nps.gov/plants/medicinal>

----- Forwarded by Patricia De Angelis/ARL/R9/FWS/DOI on 06/03/2010 09:19 
AM -----

ForestRuss at aol.com 
Sent by: mpwg-bounces at lists.plantconservation.org
06/02/2010 11:39 PM

To
MPWG at lists.plantconservation.org
cc

Subject
[MPWG] Japanese stiltgrass disease update June 2 2010






MPWG:
 
The disease that was discovered to be killing Japanese stiltgrass, 
Microstegium vimineum, in Calhoun County, West Virginia during 2008 and 
2009 has spread to new sites. The first signs of disease this year was in 
scattered locations starting about May 7. 
 
In areas where the disease was active last fall there was limited 
germination of stiltgrass this spring and many plants that have developed 
in those areas now show disease signs. 
 

Two years ago this road was completely dominated by stiltgrass that grew 
so tall and thick that all the water bars on the road were obscured.  This 
area was hit by the disease last fall as the seed was starting to set. The 
dominant greenery in this photo is black Cohosh and white aster.  Nearly 
all stiltgrass present at the site is diseased.  Within 100 feet of this 
photo there is healthy stiltgrass that is almost 18" tall. 

 PICTURE REMOVED
 
The following three photos were taken in an abandoned field area that had 
become a stiltgrass savannah.  The site has  scattered apple trees and 
deer had helped to spread the stiltgrass across the hillside.  This 
savannah covers more than fifteen acres and showed no signs of disease in 
2009.
 
 PICTURE REMOVED

The trail in the foreground has a heavy cover of sickly stiltgrass.  For 
several hundred feet of this trail nearly 100% of the stiltgrass plants 
are covered with lesions.
 
 PICTURE REMOVED
 
In some areas the thatch from last year is still easy to find because 
there is very little new growth for 2010.
 
 PICTURE REMOVED

There are areas with no living stiltgrass plants and the natives are 
taking off.
 
 PICTURE REMOVED

It appears that the fungus killing stiltgrass can survive a forest fire. 
In early April a forest fire burned over 20 acres of Crummies Creek 
including areas where I had photographed the disease last year.  Some 
Japanese stiltgrass seed survived the fire and germinated in early May but 
now nearly all plants are showing disease signs.
 
At this time no one has determined the vectors for spread of the disease 
but a paper on some of the specifics of the "Bipolaris" disease has 
recently been published by Luke Flory of Indiana University.
 
Sincerely,
 
Russ Richardson, Certified Forester
Crummies Creek Tree Farm
PO Box 207
Arnoldsburg, WV 25234
 
 
 
_______________________________________________
PCA's Medicinal Plant Working Group mailing list
MPWG at lists.plantconservation.org
http://lists.plantconservation.org/mailman/listinfo/mpwg_lists.plantconservation.org


To unsubscribe, send an e-mail to MPWG-request at lists.plantconservation.org 
with the word "unsubscribe" in the subject line.

Disclaimer
Any advice given on this list regarding diagnosis or treatments etc. 
reflects ONLY the opinion of the individual who posts the message. The 
information contained in posts is not intended nor implied to be a 
substitute for professional medical advice relative to your specific 
medical condition or question. All medical and other healthcare 
information that is discussed on this list should be carefully reviewed by 
the individual reader and their qualified healthcare professional. Posts 
do not reflect any official opinions or positions of the Plant 
Conservation Alliance. 
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.plantconservation.org/pipermail/apwg_lists.plantconservation.org/attachments/20100603/d73aacfd/attachment.html>