Elm forest, west of Minneapolis   Lee E. Frelich
  Jul 28, 2004 10:14 PDT 


Yesterday I visited a privately-owned forest of American elm, red elm and
rock elm west of Minneapolis. I had never seen such a thing before. The
main canopy is 90 feet high with trees 100-150 years old and 3-7' cbh.
There is also regeneration in the seedling and sapling size classes. Dutch
elm disease has been there for 20 years, yet most of the old elms are still
alive, even though there is several hundred acres of contiguous elm. A few
have gotten Dutch elm disease and had it for several years and then
recovered. There are some hackberry and basswood trees mixed in with the
elms. This forest is just a few miles beyond the range limit of sugar
maple, and the elms, hackberry and basswood have filled the maple's niche.

There are areas where most of the elms are rock elm. Previously I had seen
a few scattered rock elm, but never a whole stand of it.

The site also has bur oak savanna, dwarf bur oak savanna on gravel eskers,
prairie, marshes, and some lowland cottonwood forest with trees up to 25'
cbh, which were already large trees on a photograph taken in
1896. Cottonwood must live longer than we normally suppose. During the Mid
1800s the area was slated to be Minnesota's capital. Of course plans to
build the capitol there were abandoned due to the Sioux Indian wars, and
the capitol building was eventually built in Pig's Eye (renamed St.Paul,
since Pig's Eye is not a suitable name for a state's Capital city).

All of the trees in the area have the growth form you would expect for an
area at the climatic limits for tree growth, with extremely cold winters,
hot summers, frequent high winds, tornadoes and lots of lightning. Most
older trees have lightning scars, and most apparently die from blowing down
after rot initiated by lightning scars. Before I visited this site I
thought Minneapolis had an extreme climate.

Re: RE: Elm forest   Jess Riddle
  Aug 06, 2004 05:21 PDT 

Thanks for the description of the fascinating site. Do you now what
factors in addition to the position relative to the range of sugar maple
have contributed to producing the unusual canopy composition? Do
topography and soil characteristics appear to explain the unusual
concentrations of some species. Also, what other species occur in the
understory and herbaceous layer? Most of the sites where I've seen red
elm growing in near the edge of the southern Appalachians have rich,
circum-neutral soils with unusually high calcium content. Hence, in this
area, black walnut, red mulberry, and paw paw are common associates. As
far as I know, rock elm's range is no where near this area, so I can't
imagine the sites the species typically occupies.

Jess Riddle
Re: RE: Elm forest   Lee E. Frelich
  Aug 06, 2004 08:13 PDT 


This site has pH 7.0, black silt, 4-6 feet deep. Most soils at the edge of
the prairie have a lot of calcium, since wind blown silt comes in from the
Dakotas and Nebraska, which have high pH calcium rich soils. Deposition of
this silt has probably been going on for thousands of years, and continues
today. The silt holds a lot of water, so it allows development of a rich
forest even though there is nothing but grass for the next thousand miles
to the west. Some of the forest is on peninsulas and isthmuses between
lakes, so it had fewer fires than the surrounding area, thus allowing
forests to develop. The bur oak savannas are all on the south shores of the
lakes, where fires would have had an unrestricted sweep before settlement.

There are quite a few nice looking black walnut in the area, even though
the range map for black walnut shows the edge of the range about 40 miles
south of this forest. None of them are more than 100 years old, so they
must have been brought in by farmers. Red mulberry does not occur in the
area, since winters are too cold, and they would die back to the ground
almost every year (in the relative banana-belt climate of Minneapolis, 90
miles further east, red mulberry can live 15-20 years between killing
freezes of -30). Paw paw wouldn't have the slightest chance of surviving in
the area.

The understory on the peninsulas is dominated by wood nettle 6 feet tall,
with about 50 plants per square meter. In fact we got lost in the nettle
for an hour or so, since it was slightly higher than eye height and there
was no way to tell where we were going. We each got several thousand
nettle stings, but that's typical for a hike in a southern MN forest. Blue
cohosh, spring beauty, Dutchman's breeches, yellow violets, and sweet
cicely are all very common. There is a lot of elm, hackberry, basswood, and
ironwood in the sapling layer. There are also seven species of woodpeckers,
bald eagles, and pelicans in the area, and millions of mosquitoes of the
species that carry West Nile virus, cases of which are frequent in the area
during July and August.


Elm/ Oak Savannah Forest   Edward Frank
  Mar 01, 2007 15:23 PST 


Several days ago you made the comment that you had been trying to get
The Nature Conservancy in Minnesota to work toward preserving an unusual
elm forest/dry burr oak savannah forest west of Minneapolis. This is
the one you described here:


right? Is there anything I can do, or that ENTS could do to prod them
or other groups toward protecting this unusual patch of woods? Write
letters? Any suggestions?

Ed Frank
Re: Elm/ Oak Savannah Forest   Lee Frelich
  Mar 01, 2007 18:55 PST 


Yes, that is the forest. As far as I have been able to determine, it
contains the only known rock elm forest, as well as very rare oak savanna.

It might just help if ENTS wrote a letter stating how important it is to
protect the only known example of that forest type, which could be signed
by you, Will, Bob and other interested ENTS. Maybe that is something we
could do at the meeting at Cook Forest. Do we have official ENTS stationery?


== 3 of 3 ==
Date: Thurs, Apr 3 2008 8:03 pm
From: Lee Frelich


I just gave a presentation to the Minnesota Native Plant Society '"he
Kandiyohi forest: mysteries of elms and Minnesota forests of the past and
future" about the Rock elm forest in central Minnesota, along with tree
pathologist Mark Stennes, who gave some hypotheses about why this forest
has not died from Dutch elm disease even though the disease has been
present for 25 years. Some of the hypotheses are that there are native bugs
in the forest that compete with elm bark beetles, thus reducing rate of
spread, that there are native fungi that compete with the elm disease
fungus, and the possibility of resistance, as was found in the Princeton
elm, which has been commercially available for 90 years and turned by
accident to be resistant.

My part of the presentation showed that this forest may be a relic of a
much more extensive forest from the paleo record that covered millions of
acres 9,000 years ago, but that it never burned and converted to oak
savanna because it is surrounded by lakes, and sugar maple, which replaced
the elm in most locations, never migrated that far west. This is also the
only old growth elm forest I have ever seen, with trees up to 250 years old.

In addition to rock, red and American elms, the forest also has hackberry,
American basswood, green ash, Kentucky coffeetree, bitternut hickory. All
of these species have maximum abundances in eastern Kansas, which is the
same climate Minnesota is headed for by the end of the 21st Century.
Therefore, this forest is not only the past, but the future forest of

BTW--the snow in southern MN melted today with temperatures near 60
degrees, but there are still no flowers or leaves on any trees, not even
silver maple (although 2 or 3 more warm days may bring out silver maple
flowers). There is still plenty of snow to the north; the Minnesota North
Shore, and the Porcupine Mountains (south shore in MI) still have several
feet of snow and picked up a couple feet of snow Tuesday.

Lee Frelich

September 04, 2008


On your trip from St.Cloud to Pipestone, you passed within 10 miles of the Kandiyohi rock elm forest.  I was just out there today.  I am more convinced than ever that the three tracts of elm are really remnants from 9000 years ago. They didn't burn during the mid-Holocene warm period 7,500 to 5,000 bp because they are on peninsulae in lakes, and they didn't get replaced by sugar maple as the climate cooled during the last few thousand years because sugar maple never got that far west. So that left a few stands of the ancient elm forest intact.


Kangiyohi Rock Elm Forest Slide Presentation