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PHOTOGRAMMETRIC ENGINEERING 
habit of this species; this creates difficulties in 
tree counting. 
IRAQ 
Under the sponsorship of the Technical 
Assistance Programme for this country, a 
pilot forest inventory project was started in 
1954 and was finished in 1956. The objective 
was to provide the basic requirements neces- 
sary for a forest inventory of the whole coun- 
try, a total area of 18,000 sq. km, situated in 
the mountainous regions in the northern part 
of the country. 
The forest area was photographed in 1952 
on a scale of 1:40,000. Aerial photographs 
were made for the compilation of topograph- 
ical maps with a scale of 1:20,000. This ma- 
terial also proved to be valuable for the spe- 
cial forest inventory work. For this the pilot 
inventory project had to be carried out for a 
selected forest area of 540 sq. km to be put on 
a sustained yield basis. The two main forest 
types distinguished on the aerial photographs 
were oak and pine, with subdivisions in 
height and density classes. 
The interpretation of photographs was car- 
ried out on two-time enlargements from the 
original 1:40,000 photographs. In combina- 
tion with this, a field check was executed 
together with the measurement of sample 
plots for estimating timber volume and the 
annual increment. Results were found to be 
quite satisfactory. The interpretation of the 
remaining photographs can be based on this 
pilot scheme, and the forest areas with 
medium and good stocking mapped. Sugges- 
tions were put forward to start with a second 
pilot project of 300 sq. km in the near future. 
JAMAICA 
In 1959 the Forest Service started an over- 
all survey of vegetation conditions on the 
main watershed areas in relation to flood con- 
trol and run off. Aerial photographs were used 
for this purpose. By interpretation of these it 
was possible to differentiate the vegetation 
according to cover types; these were trans- 
ferred to topo sheets on a scale of 1:25,000. 
Interpretation was checked in the field and 
the maps corrected. 
The final maps provide a base from which 
acquisitions of forest areas, private forest de- 
velopment, improved agricultural cropping 
techniques etc. can be planned to improve 
watershed conditions for the future. For that 
purpose the different vegetation types ob- 
tained by photo interpretation were classified 
into two groups. The first 1s satisfactory for 
water conservation and the second comprises 
18 
vegetation types, which subject the soil to 
permanent or occasional erosion. The ratio of 
the areas occupied by the two groups will 
indicate the run off. 
This use of air photographs is an interest- 
ing example of their application in a tropical 
region and the results will be looked forward 
to with interest. In addition to this project 
the Forest Service uses aerial photographs for 
locating proposed Forest Reserves and to de- 
termine suitable areas for new forest planta- 
tions. 
NIGERIA 
It has been earlier reported that aerial 
photographs of the Nigerian forests could be 
satisfactorily interpreted. No new develop- 
ment can be reported. However, increasing 
activity may be expected soon, when new 
forest areas are photographed. The scale of 
aerial photography used for interpretation 
purposes in forestry was 1:30,000 and 
1:10,000; large-scale photography seems to 
give better interpretation results. Interesting 
results in the past were obtained in surveying 
cacao farms in Nigeria by aerial photography. 
This method made possible getting better in- 
formation on the local distribution of the 
cacao farms and for spotting insect damage. 
DUTCH NEW GUINEA 
At the request of the Dutch Government 
an area of 6500 sq. km situated in the north- 
west part of the country was type-mapped 
from aerial photographs. This work was exe- 
cuted under supervision of the I.T.C. For- 
estry Section in Delft (Netherlands). It was 
possible to complete the whole project in 
four months; the person in charge already 
had experience in the photointerpretation of 
tropical forest. 
The photographic material used for this 
purpose was obtained by a Zeiss RMK p 10 
camera. Photographs were made on a scale of 
1:40,000. The interpretation was carried out 
with the help of existing stereograms (keys), 
available literature and by general knowledge 
of vegetation in tropical countries. In this 
particular case, the following vegetation 
types could be identified on the photographs: 
dry land forests, fresh water swamp and sea 
sonal swamp forests, peat swamp forests, 
grass and reed swamps and swamp forests 
with a predominant occurrence of sago palm 
(Metroxylon sp.). Some of these vegetation 
types could be subdivided according to height 
and average crown size classes. In some in- 
stances individual tree species could be recog- 
nized on the photographs e.g. Agathis sp.