Plan your field visit
From Wikiagro.com
In this learning guide, you will learn to plan your field visit with GeoAgro GIS. You will first locate your plan area and gather information, including downloading available GIS data. This will enable you to study the area and define relevant spots, which you'll be able to upload to your GPS device.
Contents |
Webcasts
Exercise 01 – Gathering GIS data
Exercise 02 – Defining spots to visit
Exercises
Where to Do the Exercises
The first step to complete the exercises in this tutorial is to set up the computer you will be working on. If you completed our Getting Started Course, your system and datasets are ready to go through this learning guide. You will be able to use our GeoAgro GIS trial version for 2 months. From now on, you are ready to begin with any learning guide you wish.
Exercise 01 – Gathering GIS data
In this exercise you will learn to locate your planning area. Then you will learn how to check your available GIS data, and to retrieve additional layers from the internet.
Starting GeoAgro GIS
If the program is closed at the begining of this exercise, please look for the GeoAgro GIS icon at your desktop and run it by double clicking on it.
You can also run it by using the Windows® Start menu.
Locate and pan over your planning area
The first step is to locate your planing area in the GeoAgro GIS map. There are several layers you can use to help you, grouped under either “Administrative divisions” or “Base maps”.
Double click on the “Counties” layer to view the whole state.
Click on the “Rectangle zoom tool” and draw a rectangle over the Kennebec county area. GeoAgro GIS will zoom on Kennebec.
Next, you will find Asa Hutchinson Rd. Click on the “Road” layer to select it. Click on “Find objects”. 
A form will pop up. Fill it as shown below:
Click on “Accept”. An information window counting the number of results found will pop up.
Click on “Accept”. Click on the diagonal cross up left in the “Find objects” window to close it.
Drop down the “Selection” menu and click on the “Zoom to selection” tool. GeoAgro GIS will zoom to the selected feature (Asa-Hutchinson Rd)
Turn on the imagery layers to help you locate the area.
If nothing happens, click on the “Update WMS layers” icon.
Manually zoom over the planning area.
Check offline data availability
At this point you will have seen that some layers appear o disappear depending on the zoom. This is predefined to improve performance, but if you are close enough to your planning area (for example, a scale below 1:15000) you will be able to see all of the available layers. To find out whether they're turned on or not, look at the small “eye” icon besides the layer name, in the References panel. If the eye is coloured, the layer is visible; otherwise it's invisible. To make a layer visible, click on the eye icon and tick the checkbox.
Retrieve soil data
We will now download soil data for our planning area. Select the “Soils” layer.
GeoAgro GIS retrieves soils data from the USDA through web feature services or WFS. Click on the “WFS” tool to begin.
Now, select “NRCS Soils NAD84 Geographic”. 
In "Unique values field", select "SE_ROW_ID"
Click on “OK” and wait for the download to complete. If the downloading bar does not show any progress, it might be due to the WFS server not responding. Cancel your download and try again. Double click on the “Soils” layer to see the downloaded data.
Download WMS maps
You will now download DRG topography imagery from the USDA WMS servers. Click on “USDA DRG (Topo)” and tick the checkbox.
Click on “Update the WMS servers”. Wait for the data to download.
Enter the name of the layer. Click on “Accept”. 
Make “USDA DRG (Topo)” invisible by unticking the checkbox and make “Offline WMS” visible, again by clicking the checkbox.
Other available WMS layers are:
.5 Foot Imagery Wetlands 1 Foot imagery 1 Foot imagery b 2 Foot Color Imagery USDA NAIP Imagery USGS Imagery USGS DRG (Topo)
Related Articles
Find objects
How to Get Imagery and Topography Data Online
Exercise 02 – Defining spots to visit
In this exercise you will learn to locate relevant spots that you should visit when you go to the field . Then you will learn how to mark them and upload them to your GPS device.
Creating a Vector Layer
The first step is to create a vector layer named GPS points which will contain the spots you selected. Click on the ‘Add New Layer’ button in the Edit menu 
.
A dialog box will open. Select ‘Vector Layer’ as shown below and click on ‘Next’.
Fill in the form as shown below. Then click on Finish.
The new layer should be listed in the References panel under the new Field visit group:
Mark your spots
In this exercise, you will mark the two northern corners of the woods you will be working at.
Select the layer you just created (GPS Points)
Click on the “Edit layer objects” tool to open the Editing menu
Click on “Add a new object”. 
Double click on the northwestern corner to add your first spot
Proceed the same way to add the northeastern corner. By the end, your map should look like this:
Import Points to GPS Device
The first step is to assign an identifier to each point in the GPS points layer. Click on the "GPS Points" layer to select and go to the "Selection Tools" menu
. Click to drop down the options.
Click on the "Rectangle selection tool" 
and draw a rectangle enclosing the points to select them. Then go to the Edit Menu and click on 'Edit Selected Object Data'.
A data table will open. Complete the “Point” column with correlative numbers:
Next, go to the upper left-hand tab and click on GPS. This will display the window for the GPS Module of Geoagro GIS.
Go to the Tools menu and click on the 'Import from GIS Module' button.
Select the “GPS Points” layer in the dialog box. Click on Accept.
In the next dialog box, associate the Identifier field of the target layer with the Point field of the source layer. Click on the ""Point" attribute in the right panel, drag and drop in the "Identifier" attribute in the Left panel. Click on Accept.
The points in the “GPS Points” layer have been imported to the map.
Now, physically connect your GPS to your computer the way you're used to, then click on the ‘Connect to GPS Device' button.
After connecting to the GPS, click on the ‘Export Objects to GPS Device' button.
Thus, the georeferenced points with their corresponding identifiers are stored in the GPS device and ready to be set out on site.
Related Articles
Create vector layer
Add new object
GPS Module
Import from GIS module into GPS module
Upload objects to the GPS device
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