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ECONOMIC ANALYSIS OF ONTARIO 
FARMS FROM AERIAL PHOTOGRAPHS 
Robert A. Ryerson 
Canada Centre for Remote Sensing-^- 
Government of Canada 
Ottawa, Canada 
ABSTRACT 
In the past photo interpretation methods have been develop 
ed to obtain livestock numbers on dairy and beef farms in south 
ern Ontario. The methodology reported here carries on from this 
previous research to analyze the full range of crop, dairy, beef, 
swine, and mixed farm operations found in southern Ontario. 
Dollar output per individual farm, based on estimated crop, live 
stock and milk products sold results from the application of the 
method to 1:15840 panchromatic imagery. 
Although the basic inputs that must be interpreted are 
simple (crops present and building use analysis) and the method 
may be applied by "non expert" interpreters, the accuracy of 
prediction is over 95% for all farm types. 
The level of accuracy is a function of the reference 
level, or knowledge used by the interpreter, that is built 
into the method itself. Through paying more attention to 
reference level and handling of interpretation derived data 
much more information may be obtained from simple interpreta 
tion of unsophisticated imagery than was previously believed 
possible. 
RESUME 
Dans le passé, des méthodes d'interprétation des photos 
ont été mises au point afin de déterminer le nombre de tetes 
de bétail sur les fermes laitières et les fermes d'élevage du 
sud de l'Ontario. Les méthodes que rapporte ici l'auteur 
Formerly University of Waterloo, Waterloo, Canada. 
The opinions expressed are those of the author and 
do not necessarily reflect those of the Canada Centre 
for Remote Sensing or Government of Canada.