Copyright by Paul Shawn Joseph Marceaux 2011 - Repository ...

and it is just outside of the study area to the northeast. Numerous springs flow
continuously in the sandy areas of the study area, but the majority are small.
CLIMATE
Warm temperatures with abundant precipitation are characteristic of the
south temperate humid section of the United States. The summers are generally
long and warm, with winters that are short and mild. For example, in
Nacogdoches County the average temperature in winter is 48°F, with an average
daily minimum of 36°F. The summer average temperature is 81°F, with an
average daily maximum of 93°F (Dolezel 1980). Annual precipitation in modern
times averages 120‐125 cm, although generally the distribution throughout the
year is not even. Around 63.5 cm of rainfall, approximately half of the total
annual precipitation, occurs in April through September, correlating well with
the growing season for most crops.
The long growing season extends from late March to early November,
with 222 to 255 days between the last freeze of spring and the first freeze of the
fall (Creel 1982a; Perttula and Nelson 2006). This makes it possible to plant two
crops, a Caddo agricultural practice verified by the historical record (Hatcher
1927:156). Nevertheless, droughts are not uncommon in the summer. When the
rains do come in the summer, they are often torrential and can cause flooding of
cultivated bottomlands. Dendrochronological analyses of tree rings suggest there
were numerous wet and dry spells over the last 1000 years (Stahle and
Cleaveland 1994, 1995).
GEOLOGY AND SOILS
In geologic terms, the WGCP is a relatively young area made up of belt‐
like strips that approximately parallel the modern Gulf of Mexico coastline. In
24