The second study objective deals with the inter- 

 preter's ability to identify the species of green and 

 mortality trees. Species identification of 1-year 

 and 2-year mortality trees is summarized in tables 

 5 and 6. The results indicate that we can identify 1 - 

 year mortality by species with reasonable accu- 

 racy on either 1 :1 600 or 1 :2400 scale color aerial 

 photography. However, species identification of 2- 

 year mortality is very poor. 



On 1 :1 600 scale photography, 88 percent of the 

 1-year mortality trees identified on the photos 

 were assigned the proper species identification. 

 Species was assigned properly to only 44 percent 

 of the 2-year mortality trees. On 1:2400 scale 

 photography, 91 percent of the 1-year mortality 

 trees were properly identified. Species was prop- 

 erly assigned to 83 percent of the 2-year mortality 

 trees. However, so few 2-year mortality trees were 

 included in the sample that this is probably not a 

 true indication of the interpreter'sability to identify 

 species of 2-year mortality on 1:2400 scale pho- 

 tography. 



Green tree species identification has only been 

 tested on 1:1600 scale photography. However, 

 the results of testing the accuracy of species 

 identification of mortality trees indicates that one 

 should expect very little difference in interpreter's 

 ability to identify species on 1 :2400 scale photog- 

 raphy. Of the 80 green trees selected on the 

 1:1600 scale photos, 95 percent were correctly 

 identified. Thus, it is anticipated that on 1:2400 

 scale photos properly trained interpreters will also 

 be able to accurately identify the species of close 

 to 95 percent of the green trees. 



Table 5.— Species identification of mortality 

 trees on 1 :1 600 scale photography 



Identification Dead 1 Dead 2 



year years 



Species correctly 28 8 

 identified 



Species incorrectly 4 10 

 identified 



Missed 10_ 1_0 



Total 42 28 



Table 6.— Species identification of mortality 

 trees on 1 :2400 scale photography 



Identification Dead 1 Dead 2 



year years 



Species correctly 20 5 

 identified 



Species incorrectly 2 1 

 identified 



_7_ 1_2 



29 18 



Missed 

 Total 



6 



