of Long Term Research Conducted by the Northeastern Research Station
Watershed Study on the Dilldown
Unit of the Delaware-Lehigh Experimental Forest
||1) To test methods of establishing commercial forest stands
on the brush-covered lands.
2) To determine the effects of the conversion on water yields.
3) To evaluate basic relationships between vegetative growth
||The watershed is on State Forest lands near Blakeslee, PA.
located on the Pocono Plateau in northwest PA. approximately
41 deg 02 min N.Lat. and 75 deg 32 min W.Long. Soils are stony
to bouldery sandy loams with a leached A2 horizon, and they
range in depth from 2' to 5'. The mineral soil is covered with
a fibrous humus that almost completely prevents erosion. Parent
rock is sandstone with some shale. Except for a riparian zone
along Dilldown Creek, and some isolated spots, the watershed
is covered with typical scrub oak (Quercus ilicifolia) vegetation
with associations of pitch pine, gray birch, sassafras, red
maple, and red oak -- 92% is brush (scrub oak) and 8% is high
forest (riparian hardwoods and conifers within 800' to 1000'
of the creek) and swamps comprise ~5% of area. Annual Precipitation
average is 55" with a high of 76.84 inches and low of 39.73
inches within a 12-month period.
Dilldown Creek, tributary to Mud Run, is about 2.25 miles
long and a little more than a mile in average width. The watershed
is 1,529 acres in size. Elevation ranges from 1670' at the
stream gaging station to 2215 near Pohopoco Fire Tower. Slopes
on the northeastern side of the watershed are generally steeper
and more rugged than slopes on the southwestern side.
||Single watershed calibration techniques, water budget analysis.
|Likelihood of Locating Study Areas:
||Portions of the watershed were converted from scrub oak to
coniferous forest stands. Fire protection allowed the development
of hardwood forest vegetation on portions of the watershed.
||Water level recorders, hydrothermographs, intensity and standard
raingauges, and automatic streamflow recorders were used to
collect readings. Within the 1,529-acre watershed, the following
recording instruments were placed: 4 recording rain and snow
gages, 3 rainfall interception stations (2 in scrub oak, 1 in
timber near stream), 4 permanent soil-moisture stations, 6 wells
with a water-stage recorder, 1 Columbus deep-notch weir with
a water-stage recorder, 2 climatic stations with rain and snow
gages, thermograph, and anemometer (1 also with a Nipher-type
windshield, standard 4' evaporation pan, and equipment for measuring
fuel moisture for fire hazard condition measures). Data were
compiled and correlated to develop predictions of runoff, estimation
of evaporation, estimation of ground water storage, and estimations
for water storage changes.
|Variables and Sampling Frequency:
||streamflow (CFS,CSM, inches)
air temperatures (degrees F) & humidity
precipitation amount (inches) & intensity
groundwater levels (inches): 1948-1994
||USGS followed standard procedures when installing the weir
and recording instruments. Observer and instruments checked
||Paper (16 file cabinet drawers) & USGS streamflow automation
|Global Change Research Applications:
||Studies of Ecosystem Processes
|Publications and Reports:
||Reigner, I.C. 1964. Calibrating a watershed by using climatic
data. Res. Paper NE-15. Upper Darby, PA: U.S. Department of
Agriculture, Forest Service, Northeastern Forest Experiment
Station. 45 p.
Storey, H.D., compiler. 1951. Forest and water research project
Delaware-Lehigh Experimental Forest report No. 1. Harrisburg,
PA. Commonwealth of PA Department of Forests and Waters. 44
report No. 2. 1953 23 p.
report No. 3. 1955 17 p.
report No. 4. 1961 35 p.
Bethlahmy, N. 1953. Estimation summer evapotranspiration
losses in a Pennsylvania scrub oak forest. Soil Sci. 17(3):
McNamara, E.F.; Reigner, IC 1955. Root competition slows
growth of plantings on unprepared sites in scrub oak. Res.
Note 54. Upper Darby, PA: U.S. Department of Agriculture,
Forest Service, Northeastern Forest Experiment Station. 3
Eschner, A.R. 1960. Effect of scrub oak and associated ground
cover on soil moisture. Station Paper No. 133. Upper Darby,
PA: U.S. Department of Agriculture, Forest Service, Northeastern
Forest Experiment Station. 16 p.
Reigner, IC 1966. A method of estimating streamflow loss
by evapotranspiration from the riparian zone. For. SCI 12(2):
McQuilkin, W.E.; McNamara, E.F. 1967. Tree planting in scrub
oak areas after site preparation with heavy equipment. Res.
Paper NE-60. Upper Darby, PA: U.S. Department of Agriculture,
Forest Service, Northeastern Forest Experiment Station. 26
||Richard Birdsey, USDA Forest Service, 11 Campus Boulevard,
Suite 200, Newtown Square, PA 19073. (610) 557-4091.
||USGS; PA Dept. of Environmental Resources - Bureau of Forestry.