The study reported here was initiated largely because of 

 the lack of a sufficient unit of measurement for making 

 decisions on the potential use of p-j woodland resources. 

 Because of the growth habit of p-j and its various potential 

 wood products, biomass was selected as the unit of 

 measurement to be evaluated and determined in this study. 



Objectives of the study were to: 



1. Develop prediction equations that use measureable, 

 independent tree variables to estimate aboveground 

 biomass as related to resource potentials and quantity 

 of fuel. 



2. Obtain data for analysis of growth relations and site 

 quality of pinyon-juniper in Nevada. 



METHODS 



Study Locations 



Study locations were selected from stands that facilitated 

 access and tied in with other studies in the p-j. Although 

 a majority of the study sites were in western Nevada, an 

 east-west transect of sites was established across the 

 central portion of the state. Analysis showed no significant 

 difference between the western sites and the east-west 

 transect sites. Thus, the study locations appear to be 

 fairly representative of typical p-j woodlands found in 

 Nevada. The geographic distribution, specific locations, 

 and physiographic features of the 19 study sites are in 

 appendix A. 



Sample points were established at each study site. 

 Points that showed evidence of recent fire, cutting, 

 chaining, or other disturbance were avoided. Once a 

 sample point was established at a site, the nearest tree of 

 each species in each diameter class was sampled. The five 

 diameter classes based on diameter at the root collar 

 were: 



(1) <4 inches ( <10 cm) 



(2) 4-8 inches (10-20 cm) 



(3) 8-12 inches (20-30 cm) 



(4) 12-16 inches (30-40 cm) 



(5) >16 inches ( >40 cm). 



This selection method provides approximately equal 

 coverage of all size classes in the stand. 



Field Techniques 



For each sample tree selected, various crown variables 

 were estimated and recorded. Before felling, the lower 

 branches and most of the larger upper branches were cut 

 flush to the main stem and placed on weighing tarps by size 

 classes. After felling, the entire above-stump portion of 

 the tree including all previously cut branches were 

 separated into four classes and weighed using a load 

 cell attached to a boom extended from the rear of a pickup. 

 The four size classes weighed separately were: 



(1 ) > 3 inches (>7.6 cm) diameter outside bark (d.o.b.) 



(2) 1-3 inches (2.5-7.6 cm) d.o.b. 



(3) < 1 inch (<2.5 cm) d.o.b. 



(4) deadwood— all diameters. 



Although all deadwood was weighed together, occular 

 estimates of the percent in each of the size fractions was 

 recorded. All tree weights of the above size classes were 

 recorded to the nearest 1 pound using a digital meter. 



The proportions of foliage, twigs less than 0.25 inches 

 (0.64 cm) and branches 0.25 to 1 inch (0.64 to 2.5 cm) were 

 determined by subsampling approximately 10 percent of 

 <1 inch (<2.5 cm) size class fraction (fig. 1). Cross- 

 sectional disks were taken along the main stem(s) at stump 

 height, at 4-ft intervals, and at points where the d.o.b. 

 measured 6 inches (15 cm), 3 inches (7.6 cm), and 1 inch 

 (2.5 cm). Disks (2.5 cm and 7.6 cm) were also taken from 

 randomly selected branches greater than 3 inches (7.6 cm) 

 d.o.b. beyond the butt swell, usually about 5 cm from the 

 cut end. These disks, along with samples of twigs, foliage, 

 and deadwood, were weighed in the field using spring 

 scales of varying capacities and sealed in plastic bags for 

 laboratory analysis. 



Tree Measurements 



The growth form of p-j trees is such that some tree 

 measurements, especially stem diameters, were quite 

 difficult to obtain before the destructive sampling process 

 began. Thus, the tree measurements listed below are in the 

 order obtained during the sampling process and do not 

 imply any relative rank of importance. 



Measurements before any limbing or felling: 



(1) Crown class (dominant, codominant, intermediate, 

 or suppressed) 



(2) Foliage class (dense, medium, or sparse) 



(3) Crown form (rounded, oblong, triangular, tapered, 

 or irregular) 



(4) Crown projection (on ground) 



Before felling: 



(5) Number of stems (greater than 3 inches [7.6 cm] 

 d.o.b.) 



-at root collar 

 -at stump height 

 -at breast height 



(6) Number of forks (greater than 3 inches [7.6 cm] 

 d.o.b.) 



(7) Stem diameters (d.o.b.) 

 -diameter at root collar (d.r.c.) 



-diameter at stump height (d.s.h.) (12 inches [30cm]) 

 -diameter at breast height (d.b.h.) 



After felling: 



(8) Total tree height (includes stump) 



(9) Maximum crown diameter (across the stump) 



(10) Minimum crown diameter (across the stump) 



(11) Tree age (at stump height). 



The individual tree measurements are tabulated by 

 species in appendix B. 



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