ILLUSTRATED FLORA OF EAST TEXAS - Brit - Botanical Research ...

80 INTRODUCTION/PRESETTLEMENT, EARLY SETTLEMENT, RECENT CONDITIONS OF PINEYWOODS
Climate extremes, especially droughts and low temperatures are likely more important
than average conditions for excluding non-adapted species from the Pineywoods and maintaining
natural vegetation patterns on the landscape. For example, Ilex opaca (American
holly), a native broad-leaved evergreen characteristic of mesic sites, has become common in
recent years on a variety of upland sites. Following the severe summer drought of 2000, it
was possible to observe a “kill line” on many hill slopes above which this species had died on
the higher and drier topographic positions and below which it had survived on more mesic
sites (J. Van Kley, pers. obs.).
Human activities involving fossil fuel use and forest clearing have contributed to a 31%
increase in atmospheric CO2, since the industrial revolution. Global warming, changes in precipitation
patterns, and more irregular weather patterns are among the predicted results (Houghton
et al. 1995, 2001). Balancing on the eastern edge of a dramatic precipitation gradient, the
Pineywoods are potentially vulnerable to even small climatic shifts. Increased transpiration
resulting from warmer temperatures, more frequent summer droughts, and/or reduced rainfall
could cause an eastward shift in the forest boundary and the replacement of Pineywoods forests
with scrubland. Many Pineywoods trees (e.g., Quercus alba [white oak], Liquidambar styraciflua
[sweetgum], Acer rubrum [red maple], and Fagus grandifolia [American beech]) are temperate
species at the southwestern (hot, dry) corner of their ranges. Vegetation will be important in
monitoring effects of any climate changes, and baseline vegetation data are critical if we
are to document any long-term changes.
PRESETTLEMENT, EARLY SETTLEMENT, AND MORE RECENT CONDITIONS
IN THE PINEYWOODS
As in modern times, the landscape of the presettlement and early settlement Pineywoods
was a mosaic of different vegetation types, each responding to local patterns of soils, topography,
and disturbance. Native Americans, primarily various Caddo tribes in the north and
central parts of East Texas and the Atakapas to the south (Newcomb 1961; Smith 1995; La
Vere 1998, 2004), had long inhabited and modified localized areas (e.g., cultivated fields
in river bottoms), but in general the region was a vast area of forest and woodland (Phelan
1976; McWilliams & Lord 1988). Pines dominated in some areas, hardwoods in others,
and mixed forests in still others. However, even prairies were present in some areas with
special soil conditions.
The earliest known non-natives to enter the Texas Pineywoods were members of the
Spanish Moscoso Expedition led by Luis de Moscoso Alvarado, who replaced Hernando De
Soto upon his death. The expedition entered East Texas in 1542 and continued west perhaps
as far as the Brazos River (Bruseth 1996). One of the earliest descriptions of the Pineywoods
was of an area in the vicinity of modern Houston County—this was Don Domingo de Terán’s
1691 account (from Weniger 1984b):
On the 3rd, our royal standard and camp continued the march toward the north, a quarter northeast
from the aforesaid bank [of the Trinity River], penetrating through a dense wood and over a rough
country.…We marched this day five leagues. On the 4th our general muster was held and our royal
standard and camp moved forward in search of the Texas or Teija.…We made this day five leagues
through the same kind of dense woods and through a rough country.…The whole country is wooded
to a distance of about twenty-five leagues from this spot.
Somewhat later, more detailed descriptions of parts of the Pineywoods were provided by
Amos A. Parker (1968) who traveled through the area in 1834. Of the area just east of the
Sabine River, Parker noted:
After we passed the river bottom, we came to gentle swells, of red clayey soil, covered with oak,
hickory, &c. called oak openings. Sometimes we passed a small prairie…