180 
"Tree Species Identification" p 
0 
Homogenous forests gave little difficulty with respect to tree E 
species identification o In coniferous forests almost all the commercially T 
important tree species of Western Himalayas e 0 g 0 Chirpine (Pinus roxbur- b 
ghii), Bluepine (Pinus wallichiana), Deodar (Cedrus deodara), Spruce (‘ 
(Picea smithiana), Fir (Abies pindrow) could be recognised by a combina- b 
tion of known pictorial elements. The added advantage is that they occur ti 
gregariously. Most of the photo interpretation keys are of Dichotomous s 
type in which the characteristics of individual species distinguishes it ^ 
from other. For the Himalayan region September-October has been known 
to be the best season of photography from all points of view and the charac- e ' 
teristics of the few important species are described. Sl 
b< 
i) Chirpine : light grey in tone with rounded crowns and k 
coarse texture» tc 
lc 
ii) Bluepine : lighter in tone than Chirpine, big rounded crowns ^ 
and coarse texture. Apart from the tonal differ- 01 
ence, the two pines seldom occur together and 
have distinct altitudinal zonations, thus are 
easily recognised and separated. Tl 
ui 
iii) Deodar : crowns are more pointed and singly appear very b< 
small on aerial photographs. As a group, it i r 
appears in medium grey tone with fine mat like tr 
texture. The pattern is characteristic. g] 
O] 
iv) Spruce : appears in dark grey tone, with globose and fi 
diffused crowns. Pi 
v) Fir : crowns are in dark tone and pencil like shape. "1 
It can be very well separated from spruce trees 
with which it occurs in mixture. However, the 
type is generally classified as mixture because ui 
of their equal commercial utility. he 
01 
Separation of conifers and Hardwoods is easier. Out of Hard- g< 
woods, Oaks (Quercus species) are in dark tone, uniform height and he 
irregular crowns. Separation into individual species is done only on the w 
basis of altitudinal zonations. Other hardwoods like Acer species, fi 
Fraxinus sps, Juglons sps. occur in cool and moist sheltered valleys se 
with coniferous forests. They appear lighter in tone with irregular gi 
conopy. Identification criteria is mostly location and association. re 
re 
In the majority of broadleaved tropical forests, only few spe- E): 
cies have given distinct appearance. In deciduous forests Sal c] 
(Shorea robusta) and Teak (Tectona grandis) are the chief commercially li 
important species and their identification is easy. Sal if photographed Wi 
in December appears darker in tone than other hardwoods, with well ar 
defined rounded crowns and coarse texture, but when photographed in cl 
March it appears lighter in tone than other hardwoods because of partial fo 
yellowing of leaves. Teak if photographed in October-January appears oi 
in white tone with coarse texture and can be easily identified on single H