NJ Natural Heritage Program, NJDEP Division of Parks and Forestry, Office of Natural Lands Management, 22 S. Clinton Ave, Plaza Bldg 4, Fl. 4, PO Box 404 Trenton, NJ, 08625-0404
GPS readings for other 3 plot corners: 1-SE) 41.01091, -74.91581; 2-SW) 41.01088, -74.91586; 3-NW) 41.0109, -74.91587
Shape
Rectangular
Area
10
m²
Permanence
permanent plot
Layout Narrative
Plot is 2 x 5 m at 19-21 m along transect. Transect endpoints are permanently marked with rebar. Distance and compass bearing measurements to the plot location with measurements of plot orientation off the transect were taken. GPS coordinates for each corner of the plot was taken with submeter accuracy.
Environment Fields:
Elevation
146
m
Slope Aspect
322
º
Slope Gradient
20
º
Topographic Position
Lowslope
Landform
sinkhole (undifferentiated)
Landscape Narrative
General Landscape Description: Large sinkhole pond with smaller pond above on ridge divide (connected via surface water at high water levels), with karst terrain on NE-SW oriented dolomite ridges. Surrounding area contains calcareous forest and active farmland. Nearby White Lake exhibits remarkable marl deposits (up to 50 feet deep) around the periphery. The lake occurs in a pre-pleistocene karst valley with a glacial till-dam at the lake outlet on the south side. Piggyback Pond is a solution sinkhole in the karst watershed with dramatic seasonal water level fluctuations. Land use history shows evidence of agriculture, lgging and mining.
Soil Texture: Mineral - sandy silt loam over bedrock
Landscape Setting: Solution valley, collapsed delta plain.
Environmental Comments: Fairly homogeneous. Some areas have more Boltonia, others more Aster and Panicum (S-facing). Water marks on trees indicate remarkable water level fluctuations (~18'). Plants are all depauperate.
Size, Relative to Other Occurrences: The only other sinkhole pond that has a larger occurrence of this community type is Duck Pond at Swartswood State Park.
Overall Taxon Cover Values are Automatically Calculated?
no
Plot Quality Fields:
Plot Validation Level
(1) occurrence plot: sufficient for determining type occurrence
Overall Plot Vegetation Fields:
Field Cover
50
%
Nonvascular Cover
1
%
Dominant Stratum
Herb
Growthform1 Type
Herbs
Growthform1 Cover
50
%
Misc Fields:
Observation Narrative
Community Type: calcareous sinkhole pond
General Description: Upper shoreline of sinkhole pond, rocky, steep, dominated by Boltonia aeteroides asteroides. Large, intact occurrence with minimal disturbance and no invasives.
Evidence of Community Processes: Water marks on trees indicated wide fluctuations in water levels (~18').
Other associated species present but not in plot: Acalpha rhomboidea, Cyperus strigosus, Xanthium strumarium.
Red-tailed hawk and geese are present.
