re: " With long cold winters
and short cool summers, for most of the year there would have been very
little plant material to eat." Barry Groves


Sagittari latifolia (wapato) is a wetland plant that produces a tuber that
was and is available and harvestable from about now (September) through
April in the Northwest part of the US. This plant was prolific during the
last Ice Age in North America, the North American Great Basin, Siberia and
Northern Europe according to pollen data.  It is a 'pioneering' species of
wetland plant that occupied newly open areas as the ice receded. It is
spread rapidly by waterfowl eating the seed heads and redepositing them in
new locations. So, paleolithic people had a good source of carbohydrates
available to them. Other species who may have taken advantage of this
carbohydrate include: waterfowl, beaver, muskrat and perhaps Mammoth (who
may have eaten the dense above ground biomass in the wetlands).

This tuber is prolific, with a harvest net of approximately 5,418 kcal per
hour in my experiments. I harvested it out of a pond where the water was
knee-high. Hourly gathering yields of camas were similar, 5,279 kcal,
however Sagittaria tubers are harvestable in fall and spring (and all winter
in shallow ice free mud flats and lakes though cost effectiveness drops in
deeper, colder water). The tubers can be dried, stored fresh in a cool
place, or cooked fresh. They are done within ten minutes in hot ashes, do
not need long cooking times or stones for long oven cooking, do not need
processing in order to be palatable (i.e. grinding, mashing).

Long cold winters and short cool summers would limit the productivity that
is seen now in the Northwest,  but no one can say that during the last ice
age people in North America, Siberia, Northern Europe would have had no
access to a high carbohydrate plant material to eat during the winter.
Melissa Darby