wheat regions of the U.S. and Canada was 
significantly underestimated. Figure 11 
shows Landsat segment images in the U.S., 
the U.S.S.R., and China illustrating 
strip fields, large fields, and small 
fields. At the lower left is an aerial 
photograph taken in the strip fallow 
region of the U.S. Note the prevalence 
of very long and narrow fields - a result 
of moisture-conserving strip fallow 
practices. In the U.S.S.R., where the 
fields are larger, averaging 2 km on a 
side, the LACIE acreage estimates are 
thought to be quite accurate and the 
LACIE production estimates near and at 
harvest met the 90/90 accuracy goal. 
Most encouraging was the accuracy of the 
early season estimates. For both U.S. 
winter wheat and U.S.S.R. winter and 
spring wheat, the results indicated that 
the 90/90 goal was achieved with Landsat 
data acquired 1-1/2 months before harvest. 
In Phase III, the U.S. yardstick 
region was again evaluated and the re- 
gion to be inventoried in the U.S.S.R. 
was expanded so that it took in more 
than 90% of the total U.S.S.R. wheat 
production. The coverage in Canada was 
reduced to 30 segments, where the Cana- 
dian investigators collected the ground 
truth to help solve the small fields 
and spring wheat identification problems. 
  
As noted earlier, changes were made prior 
to the 1976-77 crop year (Phase III of 
LACIE) that were thought to comprise 
significant improvements. These included 
an improved stratification of the inven- 
tory region and relocation of selected 
samples using past Landsat imagery. In 
order to extend the life of the onboard 
Landsat 2 tape recorder, decisions were 
made not to acquire data over the south- 
ern hemisphere and to concentrate investi- 
gations in the U.S., Canada, and the 
U. S.S. R. 
The three crop years of LACIE proved 
to be typical in that regions of interest 
were marked by extreme weather conditions. 
While drought conditions prevailed in 
much of the U.S. yardstick region during 
Phases I and II, timely rains in late 
April of Phase II led to near bumper crops 
as a final result. In the U.S.S.R. during 
Phase III, the spring wheat crop suffered 
from drought conditions and high tempera- 
tures and the crop was reduced from early 
season estimates of 110 million metric 
tons (MMT) to a reported harvest of only 
92.0 MMT's in January 1978. LACIE was 
thus able to evaluate the technology over 
quite a range of conditions, including 
significant shortfalls in the U.S.S.R. and 
near bumper crops in drought-ridden areas 
of the U.S. 
   
      
     
       
  
PRESOI LITION OF | ANDSNAT IMAGES 
NASA-S-78-11442