A block sets the farm up into similarly managed land parcels, and determines their climate and soil characteristics (and forestry details for Tree blocks).
After creating a new analysis, the only option available is to create a block. You have the choice of drawing your own blocks using the "Create first block" or importing a map of the farm:
Drawing your blocks
Importing a map of the farm
Adding block details
Completing blocks
Drawing your blocks
If the user chooses to "Create first block" the Add Block modal will open, this includes a map on which you can draw the outline of the block, The map location is based on the address entered when creating the farm. Drawing a block is recommended as this the model can then pull through the climate for that block location. You do not need to draw the blocks perfectly, it should simply be representative of the block so that users can understand which blocks are on the farm.
You can zoom in and out of the map using the + and - icon on the bottom left corner of the map
The drawing tools at the top of the map change the effect of clicking on the map.
The hand icon () enables the position of the map to be dragged by holding the mouse button down. The shape icon (
) puts it in to drawing mode.
The polygon () icon turns on the LINZ parcel layer, shown as orange lines, making it easier to locate farm/block boundaries. Please note these lines can not be selected, they can only be used as guide.
The tag icon () turns on and off the block name labels.
Draw the block by clicking on the map at each point of the block and then click the starting point to complete the outline. You should see the outline being created as you click on each point.
Once you've drawn your block, you will need to add Block Details (see below) before you can save and create another block.
If you need to edit any blocks after they've been drawn then select the hand icon to select the block and move any points on the block.
Importing a map of the farm
Instead of drawing block areas it is now possible the upload digital maps to OverseerFM. To do this select the "Import a map of this farm" option. You can either import an map of the farm from an existing analysis or import a new map file.
Once a map file is selected you can preview it before saving it:
Once the map is saved, the "polygons" or land parcels appear as purple "unassigned" blocks that must be assigned to blocks. To do this click Assign mapped land to a new block.
Land parcels can be assigned simply by clicking on them. The first land parcel selected will auto-fill the "Effective area" data entry for the new block. If you select more than one land parcel, a warning will appear to draw attention the to the difference between the "drawn" area and the effective area of the block - as below, where the effective area shows as 62.9ha but the drawn area is 107.6ha. This can then be manually corrected, at the same time as naming the block and selecting block type.
Once the first block is defined you can Save and create another new block by clicking the orange button.
If you find you have areas of the map which you do not wish to include in an analysis - these can be deleted by either selecting the mapped areas and deleting selected land or by choosing to delete any all unassigned land:
Adding Block details
Once you've drawn your block (or you may choose not to draw it), you need to enter some Block details. 1. From the Block type drop down menu, you must select what type of block this is:
Once block type is defined, the additional data entry fields will appear for completion.
2. Then give your block a name.
3. The effective area is populated based on the area of the drawn block. This may be an approximation depending on the drawing and topography of the land. If the actual area is known this should be changed to the actual value. The calculated area will remain in the blue box for reference.
- For pastoral blocks the effective area should include grazed areas but exclude raceways and lanes
- For crop blocks, effective area should include headlands, tracks within the block and other non-cultivated areas e.g. pasture around fence lines. These can be further redefined under the crop input options. However farm tracks should not be included.
- Fenced off areas of trees within a block should be amalgamated and entered as tree blocks
- Fenced off areas of wetland should be separated out and entered as a wetland.
4. Enter additional information:
- For Pasture blocks, the topography of a block is automatically derived using a spatially referenced slope dataset however if slope differs at a farm-level scale then users can manually change a blocks topography. Topography should be entered based on the average slope for the block based on the table below:
- For Trees and Scrub blocks, you will need to select the bush type (pines or native). You can also add a forest to a Trees and scrub block.
- For House blocks you will need to enter the number of residents on the property, select a sewage management method, and enter the % of the block that is under cultivation.
- For Fenced Wetland blocks, you will to enter the wetland area, the wetland condition, and the wetland type. For more information on wetlands see here
Completing blocks
Use the button “Save, create another” to cycle through the creation of each block. When finished select save and then from the main screen select “I have completed all my blocks”.
You will then need to finalise the total farm area. The total farm area may include some areas not declared as blocks (e.g yards and races/lanes). If you do not know the area for these 'non-block areas' you can untick the Override default farm area box and Overseer will uses default values for the non-block areas.
Then click 'Save'. You will now be able to see all the tabs to enter the remaining farm management details for this analysis.