SGS-LTER Standard Production Data: 2009-2012 Annual Aboveground Net Primary Production on the Central Plains Experimental Range, Nunn, Colorado, USA 2009-2012

The objective of the long-term ANPP study is to monitor long-term net above ground primary production of the shortgrass steppe community. There are 6 sites: ridgetop (ridge), midslope (mid), swale, ESA (replicate 1 not 2), Section 25 (SEC 25), and owl-creek (OC). Each site is located in a different landscape position or soil type on the shortgrass steppe and may be grazed or not. Ridgetop, midslop and swale are grazed and are sampled along a catena. Section 25 is grazed and is located in an upload grassland. ESA is an ungrazed upland grassland an is the control from the Ecosystem Stress Area experiment. Owl Creek is ungrazed and is located in the lowlands along the owl creek drainage. There are 3 transects with 5 plots in each transect. Plots in the grazed locations are protected by cages. Chose a random direction and distance to move the cages for the LTNPP harvest next year and re-stake the cages. Plots in the ungrazed locations are chosen randomly each year. The 3 transects are marked by rebar. Measure the distance to the random location of the five plots along each transect. Because this is a monitoring effort, true replicates across the landscape are not available and it is recommended that the transect be used in calculating mean production at each sampling location. Our harvesting protocol is: Use equipment including .25 meter metal ring, shears, paper bags and sharpies. Bring knee pads to stay comfortable while working. Clip just above crown-level, except for shrubs (shrub data have been removed from the dataset). All live plus recent dead material needs to be harvested from the plot. Both recent dead and old standing-dead are standing and both are dead, but they are not the same. You can brush the basal old-dead material away from the clipped material with your fingers and sort out other taller stems. -- check your plot over before moving to next one.
Plots are clipped by species. It is usually easier to first clip species other than BOGR-BUDA. There are three cactus species on the site. Only current year growth of OPPO is clipped - these are the small pads. (OPPO data have been removed from the dataset) The two 'barrel' cactus are not clipped. There are only some times when combining of species may be done, but it is important that the following 'combining-rules' be followed:
1) The only time combining is allowed is when two species are each less than a gram (this is a few leaves, or one very small stem of an individual). 2) Some species are never combined even if there is only a very small quantity - these are BOGR, BUDA, SPCO, and CAHE. 3) When combining, never combine forbs with shrubs, grasses with forbs, etc. Only combine grasses with
grasses, forbs with forbs, shrubs with shrubs. Envelopes with combined species should have codes for all species on the envelope.

Do not clip on an ant mound or large disturbance. Note all small mammal, ant, and any other disturbances on the bag. Place all envelopes or small bags from each plot into the largest sample bag from that plot. This is usually, but not always, the BOGR bag. If there happen to be two or more large bags from one plot, try to keep them together. If there are, for example, three bags for one species, label the bags "1 of 3, 2 of 3, and 3 of 3".