Plant Density at Permanent Quad Locations on the Jornada Experimental Range, 1915-ongoing

This ongoing data set contains counts of perennial forbs and subshrubs
in 122 1m x 1m quadrats on the Jornada Experimental Range in the
northern extent of the Chihuahuan Desert of New Mexico, USA. These
quadrats were established to investigate livestock grazing effects on
plant community dynamics as well as responses to variable climatic
conditions over time. Vegetation monitoring is carried out by charting
the locations of forbs and subshrubs within each quadrat. Quadrats
were established at different times, with start dates from 1915 to
1935. Specific quadrat locations were selected for a variety of
reasons, but the overall intent was to represent varying plant
community conditions across the Jornada Experimental Range. From 1915
to 1924 charting was done by dividing the quadrat frame into a
decimeter grid using straps and reproducing locations of plants on
grid paper. From 1925 to 2016 charting was done using a pantograph.
With few exceptions, quadrats were charted until 1947, and a portion
of the quadrats were charted intermittently between 1947 and 1979.
Sampling resumed again in 1995 and continues every 5-6 years. Charts
are digitally scanned, georeferenced, and chart features are digitally
reproduced by hand. This data set is not yet complete; charts are
actively being processed by Jornada Experimental Range staff and will
be updated to this data package as they become available. A companion
data package of basal cover of perennial grasses and canopy cover of
shrubs is also available for this project (data package
knb-lter-jrn.210351001).