Test strips

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This wizard will help you to create test Strips on your fields.

The use of this tool assumes a basic understanding of on-farm research concepts. You may review this Webinar - on-farm research, to learn more about this.

1. Start the create test strip wizard

Click on the Edit objects panel Image:GIS_gis_Edit_05_01.jpg, and Select the Create test strips tool Image:GIS_gis_Edit_17_01.png.

2. Create reference line 

The following window will pop up; the first step of the wizard is to create the reference line. This is an important step because the "orientation" and "length" of the strips will be based on this line.

Click on Create reference line, and the window will be hidden until you finish drawing the line.

Please note that at least one of the end points of the reference line must be located outside the underlying polygons (reference layer) over which we will intersect the test strips. The concept of the reference layer is explained below.


Image:GIS_gis_Edit_17_02.jpg


3. Enter test strips parameters

Once the reference line is drawn, the wizard will be visible again, in this step  you will need to enter test strips parameters.

For illustration purposes, in the example below, we are assuming that we will conduct on-farm experiments to verify differences between variable management by soil type, and uniform management without considering soil type differences.

Thus, we need to create some strips divided by soil units, where we would apply differential treatments, and some strips which will have a uniform treatment. In the figure below, the strips with uniform treatment are represented in light  blue, and the strips with differential treatments according to soil type have areas in different colors for different soil types.


Image:Test_strips.jpg


In order to create these strips, we need to enter the following parameters in the Wizard:

1. Reference Layer: This is the layer with the variable under analysis (in the screenshot above: Soil Type). In order to be drawn properly, the edges of this layer need to intersect the test strips. Otherwise, the tool will not create any strips.

2. Target Layer: this is the layer where the strips will be created. You can select between an existing layer from the drop-down list, or create a new layer.

Note Note: Since you would like to apply different treatments on the created strips, it's recommended that the Target layer has been assigned a structure 'Prescription' (or a similar structure) which includes input, rate and operations field columns. For more information about data structures please review Structures Management

3. Test width: it is the width of the test strips (in the selected Units), usually related with the width of the equipment that you will use.

4. Number of samples: this is the number of strips that will be created.

5. Distance: distance between the strips (in the selected Units).

6. Orientation: strips will be drawn to the right or to the left of the reference line.

Every time you input a value, the results will be shown as a preview.

Image:GIS_gis_Edit_17_03.jpg


4. Assign prescription data for each strip (optional)

The purpose of this option is to assign input rates to each test strip area. This option is available if two conditions are met:

  • have the option 'Add prescription data for each strip' checked.
  • that the the test strips Target layer has been assigned a structure 'Prescription' (or a similar structure) which includes input, rate and operations field columns. For a complete list of required columns, see Prescription structure.


If these two conditions are met, when you click next you will see this window:


Image:GIS_gis_Edit_17_04.jpg


1. Rate: input amount.

2. Operation: name of the treatment.

3. Input: supply used on the treatment.

4. Unit: measurement units used for the input rate.


5. Delete overlapping on the target layer (optional)

This option is available when the target layer is an already existing layer. If you select this option, the wizard will analyze the target layer for overlaps between the objects and the strips. If an overlap is found, the object will be "cropped" by the overlapping strip.


Image:GIS_gis_Edit_17_05.jpg