INTRODUCTION 



A study of tree growth and stand development in pinyon- juniper (Pinus monophylla- 

 Juniperus osteospevma] woodlands of the Great Basin was initiated in 1977. Meeuwig and 

 Budy (1979) 1 measured, analyzed, and reported on three pinyon plots in the Sweetwater 

 Mountains, 130 km (80 mi) south- southeast of Reno, Nevada. During the summer of 1978, 

 five more plots were measured: three in the Paradise Range 190 km (120 mi) east- 

 southeast of Reno, one in the Monitor Range 300 km (190 mi) east-southeast of Reno, and 

 one more in the Sweetwater Mountains. These plots were located on firewood sale areas, 

 but on sites with no evidence of recent cutting or other disturbance. Except for 

 one plot in the Paradise Range, the plots were located in the oldest undisturbed stands 

 that could be found in the sale areas. All five plots were predominately pinyon, but 

 contained some juniper. Understory was sparse on all five plots. 



METHODS 



The procedures followed in 1978 were essentially the same as those of the previous 

 year, except no trees were weighed. The plots were 30 m square. A crown map was pre- 

 pared for each plot, showing locations of all trees taller than 1 dm. 



All trees taller than 2 m were felled and their total height was measured with a 

 tape. Stump height was about 15 cm unless limbs or other irregularities made it 

 necessary to cut above or below this height. On all felled trees, stem sections were 

 taken at the stump, at about 3 cm diameter on the dominant leader and at two intermediate 

 points on the dominant stem. The ages of these sections were determined by annual ring 

 count and height-age curves were plotted for each tree. These curves were extrapolated 

 to ground level to estimate tree age, and interpolated to determine past height at any 

 particular time. 



Stump diameters outside bark (d.o.b.) were measured with a diameter tape. A few 

 trees had more than one stem at stump height. Equivalent diameters of these were 

 calculated by taking the square root of the sum of the squared diameters of the 

 individual stems. 



Total aboveground biomass, foliage mass, and mass of wood in stems and limbs larger 

 than 3 inches (76 mm) diameter were calculated for each tree using regression equations 

 developed from data obtained in another study (Miller, Budy, and Meeuwig, in preparation). 

 These equations are defined in appendix A. 



Meeuwig, Richard 0., and Jerry D. Budy. 1979. Pinyon growth characteristics in the 

 Sweetwater Mountains. USDA For. Serv. Res. Pap. INT-227, 26 p. Intermt. For. and Range 

 Exp. Stn., Ogden, Utah. 



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