Spring Mill State Park, Indiana   Kirk Johnson
  Jun 07, 2006 09:26 PDT 

Has anyone ever been to Spring Mill State Park in Mitchell, Indiana? I was
talking to an Allegheny National Forest forester last week who used to work
for the Hoosier National Forest. He told me about a stand of old-growth
white oak he used to visit there from time to time when living in Indiana.

He told me some of these oaks were likely 6+ feet in diameter with very
straight, clean boles. He said the largest branches in the crowns appear to
be as big around themselves as an average large white oak bole one might see
in the woods elsewhere.

I searched through the ENTS website a bit, but didn't find a mention of
Spring Mill State Park, but I could be mistaken.

Kirk Johnson


Spring Mill State Park
Box 376
3333 State Rd. 600 East
Mitchell, IN 47446

RE: Spring Mill State Park, Indiana   fores-@earthlink.net
  Jun 07, 2006 17:28 PDT 

I believe that is Donaldson's Woods, 67 acres of perhaps the least
disturbed old-growth in Indiana.
It is in the ENTS guide, as well as others, but not sure if anyone with
ENTS has ever looked it over.
Donaldson's Woods, Spring Mill State Park, Indiana   Don Bragg
  Jul 05, 2006 12:32 PDT 


Bob Leverett had asked me to provide feedback on my thoughts about the
large timber in Spring Mill State Park in south-central Indiana before
he passed through the area. I ventured in a small part of this state
park on Monday, July 3, and came away very impressed, even though I only
looked at a tiny portion of the area. A most worthy location for future
ENTS visits!!

Spring Mill State Park is located just outside of Mitchell, Indiana in
some of the rolling karst topography of this part of the Midwest. The
park itself covers over 1300 acres, and was established in 1927, so
large areas have had a chance to recover from early settlement impacts.
The area was preserved for its local human history, as well as to
preserve the numerous caves and sinkholes that dot the landscape. The
botanical aspects of the park are also well-recognized.

One portion of the park, known as "Donaldson's Woods" is a special
"nature preserve" that appears to be old-growth, with some of the older
trees dating back 200 to 300 years. The Indiana Department of Natural
Resources has a Division of Nature Preserves that described the timber
as "undisturbed old-growth woods" with "an unusual feature [being] the
high percentage of white oaks."

I follow a short (perhaps a 1/2 mile) segment of "Trail #3" through
Donaldson's Woods, departing the east side of the parking lot for the
Twin Caves boat tour down the marked trail. It was a muggy 90+ degrees
this day, and I sweated buckets as I cherry-picked some of the larger
trees in the immediate vicinity of the trail. Shooting heights here in
mid-summer was challenging, given the dense understory of pawpaw and
sugar maple that layers beneath a midstory of American beech, sugar
maple, and other shade tolerant hardwoods. The most prominent overstory
trees were the yellow-poplars and white oaks, which reached impressive
size. Other overstory species, of variable abundance, included beech,
sugar maple, blackgum, shagbark hickory (and other hickory species),
northern red oak (and other red oaks), ash (white?), and scattered black
walnut. I am sure there are numerous other overstory species, but I had
only a limited time, and did not even attempt to get enough to produce a
Rucker Index.

As a matter of fact, I only recorded data on 7 individual trees:

Species         DBH(in.)   CBH(ft.)   SineHT(ft.)
Yellow-poplar     38.3       10.0       114.8
Yellow-poplar     57.1       14.9       127.5
Yellow-poplar     46.3       12.1       119.2
White oak         37.9        9.9       110.8
Yellow-poplar     55.8       14.6       139.6
American beech    32.6        8.5         --
Yellow-poplar     46.0       12.0         --

I ran out of time and energy before I could get heights on the beech and
yellow-poplar at the end of my hike (Bob: these trees should be
obvious--they were right next to each other, right along the trail,
across the trail from a small mound of dirt, and the beech had initials
carved in it).

To me, the yellow-poplars were the most impressive part of this portion
of the trail. Yellow-poplars 10 to 15 feet CBH were not uncommon, and I
am sure yellow-poplar in this stand will clear 140 feet, and probably
150 feet, given enough of a search effort. The site is fairly rich and
seems well-watered, especially along the small drains and sinks in the
karst areas. Some drier ridges will be noticeably less productive, but
may contain some older trees.

The white oaks were also impressive, but not as big as I hoped they'd
be. Most big white oaks along this portion of the trail were 2 to 3
feet DBH, and I'm sure other parts probably exceeded this. I would be
willing to bet that white oaks will easily clear 120 feet, and perhaps
even 130 feet or more.

I think that once this stand is thoroughly checked, it will probably
yield a 10 species Rucker Index of more than 120 feet, and has a good
chance to exceed 130 feet. There are a number of vigorous "younger"
yellow-poplar, white oak, hickory, and other hardwoods amongst the
larger, older stems, so this stand will likely continue to impress
people for a long time. I suspect that it will eventually become a
maple-beech stand, with only a scattered yellow-poplar and white oak
component in a century or two, given the abundance of these species in
the under and mid-stories.

This stand is definitely worth further visits, if you are in the general
area. It is easy to get to, and contains a lot of uncharted timber (at
least as far as ENTS is concerned). There was a $7 one-day vehicle fee
for non-Indiana residents, but I think it was worth every penny. There
are other intriguing big tree sites in the general area, including
Pioneer Mothers Memorial Forest and Hemlock Cliffs natural area on the
Hoosier National Forest. I think southern Indiana has a lot of
potential for big trees, if you know where to look.

Don Bragg

Don Bragg, Ph.D.
Research forester
Re: Donaldson's Woods, Spring Mill State Park, Indiana   Kirk Johnson
  Jul 06, 2006 10:27 PDT 

Very interesting report, I'm glad the trip was fruitful. Perhaps the
individual who told me about Spring Mill State Park had over-romanticized
his own memories of the diameter of the white oaks there, but maybe larger
ones will turn up after all.

I met Carl Harting at an Allegheny National Forest symposium here in Warren
last week. Thanks for stopping by to introduce yourself Carl!

Kirk Johnson
RE: Donaldson's Woods, Spring Mill State Park, Indiana   Robert Leverett
  Jul 06, 2006 11:45 PDT 


Will Blozan and I have long recognized that trees have two classes of
dimensions, the actual physical ones and the psychological ones. Large
forest-grown white oaks can be striking in appearance and look larger
than they actually are. The symmetry of American elms enhances their
psychological impact. On occasion, a sycamore will fool me. It will turn
out to be larger in girth than I have it pegged. Symmetry or the lack
thereof, color, bark texture, root flare all contribute to or detract
from our perception of how large a tree is. Of course surroundings have
a magnifying or diminishing effect. I can well appreciate how your
forester friend may have misjudged the actual size of forest-grown white
oaks. Been there done that.

Re: Donaldson's Woods, Spring Mill State Park, Indiana   Kirk Johnson
  Jul 07, 2006 06:50 PDT 

Those are great points Bob. I was disappointed last summer when they
high-graded a portion of the woods on the hill directly behind my house,
including removing three large-diameter white oaks. Though I never measured
them, I think they had to be 3+ feet dbh for sure.