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Part III
METHODOLOGY
Crop Selection
The selection of crops to be included in the 2009 survey was based on the crops grown within the irrigation districts
in 2007 (Table 2). It was assumed that a similar proportion of crops would be grown in 2009. Pasture was not
included. A minimum of 20 fields was set as the limit for inclusion of a crop in the survey. Based on a survey
target of 600 fields, three cereal crops, four annual broad-leaved crops, and two perennial crops were selected.
Table 2. Area of the nine crops selected for the survey and the number of fields allocated to each crop
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Irrigated area
1
Proportion of area Expected number
Crop
(1,000 ha)
(%)
of fields
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Annual
Cereal
Barley
(includes malt and silage)
95
23.7
142
Spring wheat
(includes CPS, hard spring, durum and soft)
78
19.5
117
Corn
(includes fresh, grain and silage)
20
5.1
30
Broad-leaved annual
Canola
47
11.7
70
Dry beans
18
4.5
27
Potatoes
17
4.1
25
Sugar beets
14
3.5
21
Perennial
Alfalfa
(includes hay, seed and silage)
89
22.1
133
Grass
(includes hay, seed, brome and timothy)
24
5.9
35
___________________________________________________________________________________________________________________________________________________________________________________________
Total
402
100.0
600
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Alberta Agriculture and Rural Development.
2008. Alberta Irrigation Information – Facts and Figures for the
Year 2007. Lethbridge, Canada.
Stratification of Sites
Irrigation districts were used as the strata in a stratified random-sampling procedure. The number of fields in an
irrigation district was allocated in proportion to the seeded area of the selected crops in the irrigation district, relative
to the total area seeded to selected crops in all irrigation districts (Table 3). Hectarage of field crops derived from
the 2007 irrigation informatio
. To facilitate the organization of the survey, fields allocated to irrigation districts
were subsequently allocated to counties based on proportion of each irrigation district’s area cultivated in each
municipality or county (Figure 4).
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Alberta Agriculture and Rural Development.
2008. Alberta Irrigation Information – Facts and Figures for the
Year 2007. Lethbridge, Canada.