The Wisconsin weekly blade. [volume] (Madison, Wis.) 1916-1925, 1919-08-28

rocks and stones and quicksands sloping very
gradually into deep water. There is probably no
inner freshwater bathing beach In the world.
Don't think Of the dunes heaps of bare sand
IN desert. They exactly the reverse They
have water, trees. shrubs, vines. flowers, grass.
birds and small wild animal life. The truth is that
the dunes are great natural propagating garden
with most astonishing array of trees and plants
and flowers. This garden is packed full of flora
from the Lake Superior region the Atlantic coast,
the middle South and the western prairie. 1t
seems TO have almost everything in the plant line
from cactus 10 cranberries and from pines TO tulip
trees a list of only the most characteristic and
important plant species numbers POS.
To the ordinary visitor probably the spectacle
of the walking dunes is the most interesting
Here he sees land in the making. Here today is
towering dune crowned with flowers and plants
and trees tomorrow 1t is gone and where it was Is
a great blowout of gistenng sand with It's steep
sides strewn with dead trunks exhumed from an
ancient graveyard of previous forest. Today
there is deep cash in the bluff; tomorrow its
place is taken by a very lofty heap of white
sand that has coae up grain by grain. out of the
lake, on which grasses and plants and shrubs and
treelets already struggling for fOothOld. To
day stands forest on the edge of a shallow pond;
tomorrow II is a cemetery. with even The tree
tops covered by sand marching in from the beach.
The accompanying map and diagram shows
where the material that builds the dunes is COM
ing from and how it gets there. Lake Michigan
has been taking material from the West shore ana
depositng il at the dunes for period reckOned at
about 5000 years. Previous to this period the
level of the lake was so or 60 feet higher than now
and the discharge was toward the Mississippi at
Il point near where the dunes. When the
ice gorge glacer which prevented the discharge
of water into the st. Lawrence was removed and
the lake drained into the Atlantic instead of the
gulf the level dropped the present lake currents
set in and the building of the dunes was begun.
Public land surveys made in 1880 and soundings
of Lake Michigan furnish the data for these
estimates During the last 5000 years the waters
Of the lake have washed away about 800 square
miles of land from the shore extending from the
Indiana state line northward into Wisconsin.
Where this land was is water frora 80 to 60
feet deep The old shore line extends out from
three 10 nine miles; then there is abrupt drop
of several hundred feet
This i an unparalleled erosion; II is accounted
for ~ the softneSs of the shore which is largely
composed of material that ground very fine
bv the glaciers that deposited il. 1t is estimated
that 100000 tons of soil is taken yearly by the
lake from the shore north Of Chicago. So there
Is plenty OF material for building operations at
the dunes
These facts suggest this interesting question
What win happen TO the dunes when the supply |
of building material stops!
And stop il will, and that comparatively soon |
For the shore north Of Chicago will in a few years
be pretty >oldy settled by people who have money
10 spend 70 prevent further erosion OF the SFbre |
In fact erosion has already been stopped 6yer /
long stretches, and in many places the shore has |
been built out The time coming wheo the west /
shore Will be protected from erosion by piers and
breahwaters. The supply of building material for 1
the dimes Will presumably stop Perhaps then the /
dunes will stop walking"
Let us hone that long before that time the |
Dunes National park viii be peoples playground |
dedicated 10 public recreation forever