Monitoring Aspen in the Upper Columbia Basin Network: 2008 monitoring report for City of Rocks National Reserve and Craters of the Moon National Monument and Preserve.

Strand, Eva; Bunting, Stephen

This annual report details the status and trend estimates obtained during the first two years of monitoring (2007-2008). Sampling was conducted at CRMO in 2007 and at CIRO in 2008. In CRMO 34 stands were mapped in 2006 and 108 permanent plots were established in 22 stands in 2007. In CIRO, 67 aspen stands were mapped in 2006 using remote sensing and field reconnaissance. Of these, 37 stands were visited in 2008 and 89 permanent plots were established in 16 of the stands. The remaining 12 stands visited in CRMO and 21 stands visited in CIRO were deemed unsuitable for sampling due to pre-determined criteria dictating that data collection would be limited to aspen stands in the riparian zone and that shrubby snow-damaged aspen would not be sampled. It was not feasible to sample in a few stands because of safety reasons. An additional 30 stands will be visited in CIRO in 2009. The park stem count averages for the 2007-2008 sampling effort are shown in the table below. Park Suckers1 Regeneration2 Mature3 Dead4CIRO (2008) 2644 1837 493 212CRMO (2007) 5361 1720 785 1063 1 Suckers include suckers or seedlings < 5 feet tall. A sucker is an aspen shoot originating from vegetative sprouting from another aspen tree. 2 Regeneration includes trees greater than 2.5 cm (1 inch) in diameter breast height (dbh) and shorter than 75% of the stand height. 3 Mature trees are greater than 2.5 cm (1 inch) in dbh and taller than 75% of the stand height. 4 Dead stems are greater than 2.5 cm (1 inch) in dbh.The majority of aspen stands in CIRO and CRMO sampled in 2007-2008 are regenerating and contain a distribution of age classes. There are some stands, however, with relatively low aspen stem densities, low regeneration, and/or high dead aspen stem and conifer densities. Six stands in CRMO have a regeneration < 600 stems/ha. Among these six stands, stand #26 also has a sucker count < 500 stems/ha and stand #13 has no mature stems within the sampled plots. Conifer stem counts are low in CRMO while two stands in CIRO have stem counts of mature conifers that are comparable to those of mature aspen.The aspen protocol will be submitted for final review in March 2009. The methods presented in this report reflect version 1.0 of the protocol. The power analysis is being refined to optimize the number of samples necessary for detecting trend with statistical confidence while minimizing the sampling efforts and costs. In future years, the focus for data analysis will shift toward trend analysis, in which biologically meaningful declines or increases within the park units as well as within individual stands will be reported, providing ecological decision support information and enabling development of appropriate management strategies.

Monitoring Aspen in the Upper Columbia Basin Network: 2008 monitoring report for City of Rocks National Reserve and Craters of the Moon National Monument and Preserve.

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