Hail Storm Damage   Lee E. Frelich
  Oct 03, 2006 06:28 PDT 

[Wednesday-Friday I attended the Forest Guild Annual Meeting, which this
year was at Camp Manitowish in Boulder Junction, WI. Its was a nice 5 hour
drive there and back, with 250 miles of maple trees in brilliant orange and
red. The camp normally takes school kids on wilderness trips, but also
hosts small conferences, such as Forest Guild with about 100 attendees.]

Eunice Padley, from WI Department of Natural Resources showed a sizable
stand (I think a few hundred acres) of aspen mixed with other species in
northern WI that was killed by a hailstorm this summer. From her picture it
looked like all the leaves, twigs and small branches were stripped from the
trees by baseball or bigger sized hail, leaving a stand that looked like a
bunch of telephone poles.

That's a new large-scale disturbance for my list--I have seen trees damaged
by hail before, but never a whole stand killed.

Hail Storm Damage Photos - 
Brule River State Forest, WI
  Lee E. Frelich
  Nov 20, 2006

Attached are several jpegs showing damage from the great hail storm of 
August 14, 2000 in Brule River State Forest, in northern WI.

I though you might want put them on the ENTS website since the represent 
the most extreme hail damage to forests known at this time.

Photo credits to Dave Schulz, WI Department of Natural Resources.

bark_damage.jpg (149339 bytes)
 Bark damage from hail on young aspen trees, one week after the storm.
jack_pine_top.jpg (181967 bytes)
 Bark damage to the top of a jack pine caused by hail, 
one week after the storm.
p5290019a.jpg (83478 bytes)
 Dead jack pine the spring following the hail storm (May 2001).
p6060001a.jpg (105804 bytes)
 Young aspen stand killed by large hail shown a year after the 
p8150015a.jpg (158677 bytes)
 Oak leaf litter brought down by the hail two days later.
skyhaila.jpg (114963 bytes)
 Red pine forest killed by hail shown 18 months after the storm.

Re: RE: Forest Guild/hail   brown_-@colstate.edu
  Oct 03, 2006 08:03 PDT 

I wonder if the aspen were more affected than some of the other
species. I know that ice storm damage differs in the severity for

Roger Brown
Re: RE: Forest Guild/hail   Lee E. Frelich
  Oct 03, 2006 10:04 PDT 


Aspen are probably more susceptible to all types of physical damage than
most other tree species. In our data from the Big Blowdown of 1999, aspen
was the most susceptible tree species.

I feel sorry for the birds that were in that forest. We had a hailstorm
like that one in the town where I grew up, and not only did it break every
south facing window in the city, remove the shingles from every house, and
smash every car that was not in a garage, but most of the birds were
literally mashed; they were little piles of red mush with feathers stuck in
them laying on the sidewalk after the storm.

Re: RE: Forest Guild/hail   brown_-@colstate.edu
  Oct 03, 2006 12:20 PDT 

Lee - I suspect faunal mortality in general (other than for fires) due
to severe disturbance is a relatively under appreciated / understudied

RE: Forest Guild/hail   Lee E. Frelich
  Oct 20, 2006 09:57 PDT 

Ernie et al.:

I found out more about the area damaged by hail, pictures of which I saw at
the Forest Guild meeting in September.

The storm was actually several years ago, on August 14, 2000, in the Brule
River State Forest in northwestern WI.

Apparently hail more than 2 inches in diameter driven horizontally by
strong winds stripped off chunks of bark in addition to defoliating the
trees and taking off a lot of twigs. It caused heavy mortality in 5000
acres of aspen, jack pine and red pine forest, and 2000 acres was so badly
damaged that WI DNR salvaged the timber.

Eunice Padley from WI DNR is going to send me some pictures in a few days.

Re: RE: Forest Guild/hail   paul-@tds.net
  Oct 20, 2006 11:23 PDT 


The NOAA SPC storm reports for that day are at:
I believe that the Brule S.F. is entirely in Douglas County.

The Wisconsin DNR reported:
"On August 14, 2000, a similar storm, also with golf ball-sized hail, damaged timber on approximately 25,500 acres in Douglas County. Winds as high as 60 mph were recorded. The damage was scattered throughout the 25,500 acres and injured species include red, jack, white pine and aspen. Since this storm hit later in the growing season, buds were tougher and damage to the buds appears to be less severe than from the spring storm. Other injuries included multiple stem wounds on all affected species, loss of foliage and some branch breakage." photo attached...

A story of a plane crash in the area the same day related to the storm is at:

I see my 30K attachment didn't go through this time. It came from near the bottom of http://fhm.fs.fed.us/fhh/fhh-00/wi/wi_00.htm showing debarked, fallen trees...

Paul Jost

RE: RE: Forest Guild/hail   Ernie Ostuno
  Oct 21, 2006 18:21 PDT 

Lee, Paul,

Thanks. I recall that the spring and summer of 2000 produced several
derechos through the WI/MI UP area. I know that wind driven hail can do
quite a bit of damage to cars and windows but I didn't know it could
kill a stand of trees, or even knock the bark off of them. Trees are
often debarked in strong tornadoes when hit by a blizzard of hundreds,
if not thousands, of pieces of debris of various sizes carried along by
150-200 mph winds.