ABSTRACT 



Physical fuel properties were determined utilizing meas- 

 urements of volume, surface area, and weight for ponderosa 

 pine forest floors and cheatgrass. Average values of these 

 properties for ponderosa pine needle litter and cheatgrass 

 were respectively: surface area-to-volume ratio (a), 57.6 

 and 144. cm.^/cc. ; particle density, 0. 51 and 0. 34 g. /cc. ; 

 loading, 324 and 53 g./m.^; void volume-to-surface area 

 ratio (A), 0.8 and 12,5 cc./cm.^; average particle spacing, 

 0. 66 and 1. 70 cm. ; bulk density, 0. 016 and 0. 00032 g. /cc. ; 

 andaX, 37.5 and 1810. Also presented are volume and sur- 

 face area proportions of the forest floor litter and of the 

 cheatgrass. A goodness-of-fit test showed that pine needles 

 were randomly oriented in the horizontal plane and that 

 cheatgrass particles were nonrandomly oriented in the ver- 

 tical plane. Correlation analysis indicated that bulk density 

 and particle spacing could be substituted for A , a fairly 

 difficult variable to measure. 



