In light of the recent discussion of tubers, I thought the
following two messages on the Paleodiet Symposium list might
interest some.  I'm reproducing them in their entirety, since
they are not long.

The Sagittaria Latifolia plant is also referred to as "wapato"
and "duck potato."  The climate in which it thrives is very much
like the steppe-tundra environment that Ray describes.

Todd Moody
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Date:    Fri, 14 Jul 2000 14:44:21 -0700
From:    Melissa Darby <[log in to unmask]>
Subject: Re: PALEODIET Digest - 15 Jun 2000 to 14 Jul 2000 (#2000-16)

I have postulated that in the Northern Hemisphere (North America,
Siberia, Northern Europe) as the ice sheet was retreating there
were considerable wetlands that supported Sagittaria latifolia-
an emergent wetland plant spread by waterfowl and known as a
pioneering plant because it was one of the first to colonize
these areas.  It grows as a monoculture, and can take over a
wetland. On the lower Columbia River, and in the Mississippi
delta there are places where there is no other plant except
S.latifolia for hundreds of acres. This is the model I suggest
existed ca. 10,000 b.p. in the shallow lakes, ponds, streamsides,
wetlands that were present draining the water from the icesheet.

The plants would also support grazing megafauna because wetlands
(even in cold climates) are highly productive re calories/biomass
per sq meter.  The tuber tastes like a potato, cooks as fast or
faster than a potato and does not need to be processed with stone
tools, nor is it associated with fire cracked rock, it can be
baked in hot ashes i.e. it is hard to find in the archaeological
record. It was available/harvestable from early fall to
mid-spring when plant foods are generally considered to be
scarce, and was very cost effective to harvest.  It dries well,
and can be stored for long periods of time. It has been recovered
in paleo sites in Poland, and in caves in the Great Basin.
Pollen studies support my hypothesis.  My thesis is available
upon request.  Melissa Darby [log in to unmask]


Date:    Fri, 21 Jul 2000 18:11:01 -0700
From:    Melissa Darby <[log in to unmask]>
Subject: Re: caloric requirements

Regarding calories expended and gained during foraging  for
Sagittaria latifolia.

I have calculated that the return on harvesting Sagittaria
latifolia is 1 calorie expended for 18 gained.

The tubers float when one wades around in the soft mud and
agitates its.  This ability to float assists waterfowl when they
graze, and also assisted human populations when they gathered
this plant in North America. In October while treading in the
silty mud in a S.latifolia patch in water just above my knees,
113 tubers were released from the substrate and floated to the
surface within a thirty minute time period. Keely has calculated
that there are 3.6 calories per dry gram of wapato (Keely 1980).
During this trial, I collected 1,505 grams (fresh) of wapato.
Since the dry weight of wapato is about half the weight of fresh
tubers, there was caloric net of 2,709 calories of energy.  My
expenditure of calories I calculate was the same as riding a bike
at a moderate pace at about 300 calories an hour. Of course if
the harvester has to break through ice to harvest it, or harvest
in deep cold water the cost effectiveness goes down.

Eating the tubers raw is ok, and there is ethnohistoic data that
they were eaten raw though usually cooked; but they not as tasty.
I don't know if all the carbs are available uncooked.

I agree with you that we should be looking at plants such as
these.  Some plant foods require little processing; stone tools
are not associated with their use.  I think we should be also
looking at that old paradigm that stone tools as indicators of
the intensification of plant use, and amend it.

Thanks

Melissa Darby

Keely, Patrick Byron

1980 Nutrient Composition of Selected Important Plant Foods of the
Pre-Contact Diet of the Northwest Native American Peoples. M.S. Thesis,
University of Washington, Nutritional Sciences and Textiles Dept.

Kubiak-Martens, L.

1996 Evidence for possible use of plant foods in Palaeolithic and Mesolithic
diet from the site of Calowanie in the central part of the Polish Plain.
Vegetation History and Archaeobotany (1996) 5:33-38.