Digitizing first field

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{{#customtitle:Digitize your first fields|}} 

This exercise is included in the tutorial: Getting Started with GeoAgro GIS

You can use GeoAgro GIS to generate your own maps. Learn how to add new fields to your map, and how to customize the way they're shown.

Setup a Sample Project

To go through this learning guide, you need to setup the sample project described in this guide: Create a Project and add initial data

 
GIS gis Init 03 01.jpg

Start GeoAgro GIS by double clicking on its icon at your desktop;
You may also run it by using the Windows® Start menu.
The Project Selection window will pop up. Select the "Sample Farm MO" in the learning guide Create a Project and add sample data



Digitize fields

To digitize a field, you must use a layer capable of providing you reference, such as aerial imagery or GPS points. In this exercise, we will use sample imagery from the NAIP. First, make sure it's turned on.

Image:GAGIS_TurnOn_Layers.png

Now we can begin digitizing. First, turn on and select the "Fields - Producer" layer. This is the layer we will use to digitize fields.

Image:GAGIS_Select_Fields-producer.jpg]

Then, open the "Edit layer's feature" menu on the left panel GIS gis Edit 05 01.jpg

Select the "Add a new object" tool.Image:GIS_gis_Edit_05a_01.jpg

To begin digitizing, click on each of the corners of the fields.

Image:GAGIS_Click_corners.jpg

Once you're done, double click to finish drawing.

Image:GAGIS_Finish_drawing.jpg

If you also digitize the field on the right side, you will end up with a map like the one below.

Image:GAGIS_Final_polygons.jpg


Divide fields

Sometimes you may need to divide an existing field in two or more. You may do this by using the "Divide Objects (Line)" tool

Select the field you'd like to divide using the selection  tools. Then click on the Edit Toolbar Image:GIS_gis_Edit_05_01.jpg and go to the Divide Objects (Line) tool Image:GIS_gis_Edit_05k_01.jpg

Click outside the field and then draw a line to divide the field. To finalize, continue the line outside the field, and double click.
Image:GAGIS_Divide_polygons.jpg

Your field is now divided in two
Image:GAGIS_Divided_polygons.jpg

Label your fields

To identify your fields you may need to label them in some way. GeoAgro GIS provides with this by allowing you to fill your feature with attributes. First, select the fields you'd like to label

Image:GAGIS_select_to_label.jpg

Then, go to the menu on the right side and open the "Edit selected object's data" tool. Image:GIS_gis_Edit_06_01.jpg

Now you may start filling your attributes. These attributes will be used later for labeling them. For this excercise, we will add the field names, and its crops.

Field names are stored in the attribute "Field_Name". In this example, field names are 1, 2 and 3; and can be completed as shown below:

Image:GAGIS_filling_attributes1.jpg

Then, crops will be stored in the attribute "Crops". In this example, fields number 1 and 2 are dedicated to corn, while field number 3 is for soybeans. This can be completed as shown below:

Image:GAGIS_filling_attributes1.jpg

Displaying your field labels

You have now completed filling the attributes you need to label your fields. To display those labels, you need to modify the symbology for the layer. Open the "Edit cartography and layer properties" tool.

Now open the "Symbology" tab.Image:GIS_gis_Edit_03_01.jpg

We will use the "Label" box. Open the "Attributes" drop-down menu, and select the "Field_name" and "Crop" attributes, to label your fields with the Field name and crop name you added in the previous step. Click on "Accept" to complete"

Image:GAGIS_editing_symbology.jpg

You will now see how the features in the map are labeled with the field names and their corresponding crops

Image:GAGIS_new_symbology.jpg

Related articles

This exercise is included in the tutorial: Getting Started with GeoAgro GIS