"Cass" wrote about playing in the dirt:

I know that silts is measured as a
component in some soil tests, and a review of loam will show relative
proportions of silt and clay. Good points. But I do beg to differ on
whether clay will dissolve, or at least form a suspension in water. It
will or does. I thought that clay and silt were next to each other on
the continuum of particle size, with clay being the smallest.

Hello Cass,

I, for one, like to have a definition before we start a discussion of
what we are discussing here to avoid confusion. When I was doing
my research to become a MG I become keenly interested
in the composition strata of the different soils found in the PNW and
the term "glacial till" was used often enough to send me to the nearest
library to get a more or less exact definition. FWIW, here it is, now
available of course through Google:

"Glacial till.This is that part of the glacial drift deposited directly by
the ice with little or no transportation by water. It is generally an
unstratified, heterogeneous mixture of clay, silt, sand, gravel, and
sometimes boulders. Some of the mixture settled out as the ice melted with
very little washing by water, and some was overridden by the glacier and is
compacted and unsorted. Till may be found in ground moraines, terminal
moraines, medial moraines, and lateral moraines. In many places it is
important to differentiate between the tills of the several glaciations.
Commonly, the tills underlie one another and may be separated by other
deposits or old, weathered surfaces. Many deposits of glacial till were
later eroded by the wave action in glacial lakes. The upper part of such
wave-cut till may have a high percentage of rock fragments.

Glacial till ranges widely in texture, chemical composition, and the degree
of weathering that followed its deposition. Much till is calcareous, but an
important part is noncalcareous because no carbonate rocks contributed to
the material or because subsequent leaching and chemical weathering have
removed the carbonates. " ( to which this definition was added some time
later
according to the date from another source):

"To be soil, a natural body must contain living matter. This excludes former
soils now buried below the effects of organisms. This is not to say that
buried soils may not be characterized by reference to taxonomic classes. It
merely means that they are not now members of the collection of natural
bodies called soil; they are buried paleosols.

Not everything "capable of supporting plants out-of-doors" is soil. Bodies
of water that support floating plants, such as algae, are not soil, but the
sediment below shallow water is soil if it can support bottom-rooting plants
such as cattails or reeds. The above-ground parts of plants are also not
soil, although they may support parasitic plants. Rock that mainly supports
lichens on the surface or plants only in widely spaced cracks is also
excluded.

The time transition from not-soil to soil can be illustrated by recent lava
flows in warm regions under heavy and very frequent rainfall. Plants become
established very quickly in such climates on the basaltic lava, even through
there is very little earthy material. The plants are supported by the porous
rock filled with water containing plant nutrients. Organic matter soon
accumulates; but, before it does, the dominantly porous broken lava in which
plant roots grow is soil.

More than 50 years ago, Marbut's definition of soil as the "outer layer" of
the Earth's crust implied a concept of soil as a continuum(Marbut, 1935).
The current definition refers to soil as a collection of natural bodies on
the surface of the Earth, which divides Marbut's continuum into discrete,
defined parts that can be treated as members of a population. The
perspective of soil has changed from one in which the whole was emphasized
and its parts were loosely defined to one in which the parts are sharply
defined and the whole is an organized collection of these parts."

For those who are interested in the composition of our soil - more or less
since Oregon has some different and local characteristics as well, but I am
going to dump all the states composing the Pacific Northwest into one area -
here is a very interesting link:

http://soilslab.cfr.washington.edu/esc311
507/finalprojects/jaimeyoung/uplands.html

(Of course good old OE believes in "divide and conquer" so make sure to
put all the info in one line) Good planting, everyone, glacier till or
otherwise...

Allegra