100' 
be more economical to use in relation to aerial 
photography. 
Budworm infested white spruce 
iHealthy white spruce 
* Black spruce 
Q Water 
,63 - .69 micrometer intensity 
Figure 6. Scattergram outlines of MEIS-II bands 4 and 6 
for five classes at 10 m resolution. 
COMPARISON OF MEIS-II AND TM DATA 
The MEIS and TM data were both geometrically cor 
rected and resampled to 10 m in order to compare the 
data sets. MEIS-II bands 2, 4, and 5 and TM bands 1, 
2, and 3 were each combined to give natural colour 
composites. MEIS, with its higher radiometric reso 
lution illustrated the budworm infestation more 
clearly and with less confusion with other vegetation 
types than TM. The TM colour composite with its 
higher noise levels and wider spectral band ranges 
demonstrated budworm infestation but with greater 
confusion with other vegetation types, especially in 
the wetland areas. 
Spruce budworm infestation was detectable with the 
MEIS-II data due to the superior spatial and radio 
metric resolution of the sensor. The major factor 
is, however, the narrow spectral bands, particularly 
the red band which is well positioned relative to the 
chlorophyll absorption minimum at.675 m of vegetation 
reflectance. There is some overlap between the bud 
worm infested spruce and healthy spruce but this is 
minimal, especially in the drier areas. 
ACKNOWLEDGEMENTS 
The authors would like to thank J.D. Heyland, 
F.J. Ahern and D.G. leckie for their critical review 
of this paper. 
REFERENCES 
Ahern, F.J., W.J. Bennett and E.G. Kettela, 1986. 
Surveying spruce budworm defoliation with an air 
borne pushbroom scanner. Journal of Photogram- 
metric Engineering and Remote Sensing (in press). 
Kucera, D.B. and R.G. Taylor, 1984. Spruce budworm 
situation in North America 1983. U.S. Dept, of 
Agriculture - Environment Canada, Mise. Publ. 
No. 1441. 
McColl, W.D., R.A. Neville and S.M. Till, 1984. 
Multi-detector electro-optical imaging scanner 
MEIS-II. Proceedings of the 8th Canadian Symposium 
on Remote Sensing and 4th Conference of 
l'Association québécoise de télédétection, 
Montreal, Quebec, May 1983, pp. 71-79. 
McLean, D.A. and T.A. Erdle, 1984. A method to 
determine effects of spruce budworm on stand yield 
and wood supply projections for New Brunswick. The 
Forestry Chronicle, June 1984, pp. 167-173. 
Stanley, L.W. and R.J. Reed, 1986. Report on the 
spruce budworm infestation situation in 
Saskatchewan as of September 1985, Saskatchewan 
Parks and Renewable Resources Internal Report, 
6 pg. 
Taylor, M.M., 1973. Principal components colour 
display of ERTS imagery. Proceedings of the 3rd 
ERTS Symposium, Vol. 1, Section B, NASA, 
Washington, D.C., pp. 1877-1879. 
CONCLUSION 
The results from this study indicate that it is 
possible to map current year spruce budworm infesta 
tions from natural colour images. Severe spruce 
budworm infestation appears as a reddish-brown dis 
colouration in data from an electro-optical pushbroom 
scanner and Thematic Mapper data. This suggests that 
more accurate maps could be obtained by this method 
than by traditional aerial sketch mapping. This 
capability could improve program planning and effec 
tive assessment of budworm infestation for cutting. 
It could ultimately improve the wood supply through 
better growth-loss predictions for harvest 
scheduling. 
Detection, of varying degrees of severe current 
year budworm infestation was possible by using data 
from the pushbroom scanner and TM data. The ability 
to detect budworm infestation with the TM sensor is 
diminished due to its spectral band placement, 
greater band widths, and lesser signal-to-noise 
ratio. 
In Saskatchewan the areas affected by spruce bud 
worm are quite small. With the confusion between 
budworm infested areas and other vegetation types, 
especially in the wetland areas, no improvements in 
mapping accuracy are obtained using either TM data or 
MEIS-II data over aerial photography with its 
subsequent ground check. Should, in the future, 
larger areas be affected then MEIS-II or TM data may