The SnapMap Fields tab displays general information gathered about the field. This is where you can import the field data. See Importing Data into SnapPlus and the video tutorial on Selecting Data in SnapMaps for more information.The Exists column specifies if the given field exists in SnapPlus or not. Once a field is imported this column will read Yes. The Field Borders column stores the polygon data for each field. If this column is populated for a given field, geometry exists for that field. Clicking Upload will send this geometry to SnapMaps, overwriting whatever is there currently. If no value exists, pressing Upload will remove whatever geometry exists in SnapMaps.
The first time you download your data from the website, all of the cells that are different than your field or restrictions data will be in the orange cells. When you Import to SnapPlus, only the Orange or selected cells are imported.
If some data shows up as different but you don’t want to import those cells, you may toggle the cell state (dismissed or not dismissed) by Ctrl-Click on a column or individual cells. If you don’t want to download an entire row check the Is Locked checkbox in that row.
Your can also protect/lock verfied SnapPlus data from updating with SnapMaps data by clicking the locking checkbox for that field. For more information on locking click here.
You may also click on the Refresh button to return all cells to their original state (except for the locked data).
The Delete non-existing fields radio buttons are used to remove downloaded fields. When All is clicked every field which does not exist in SnapPlus will be removed. When Selected Only is pressed, fields which are selected and do not exist in SnapPlus will be removed. Once a field is removed, you can click on the Upload button to update SnapMaps to remove the field on the website.
Save a snapshot of your data before you import the map data.
If you’ve hand entered the field slope and field slope length values on the fields screen - entered values different from the defaults - those values should not show up as orange on the SnapMaps Fields tab and will not get overwritten when you Import To SnapPlus.
When you click on the Import To SnapPlus button, the orange cell data will overwrite the data on the fields tab.
If you don’t want to import data in a cell you can press the Ctrl key on your keyboard and click the mouse in that cell de-selecting it. You can also Ctrl-Click on a row or column header cell to de-select all of the cells in that row or column.
In the image below, I Ctrl-Clicked on the Slope and Slope Length columns de-selecting all of the cells in both columns. Ctrl-Click again to toggle them selected again.
•Exists: Specifies whether field exists or not, or is inactive in the field tab.
•Watershed: The watershed that is associated with the field listed. This will only be present on the SnapMaps Tab and not on the Fields tab.
•303d or O/ERW: This shows any state listed impaired or threatened waters that may be in the field. Waters chosen to be on this list are not meeting water quality standards and may have been on the list due to exceeded total phoshorus criteria, or poor biological conditions. This will only show up in the SnapMaps Tab and will not be on the Fields Tab.
•Subfarm: The subfarm the field belongs to if applicable.
•Field Name: The name of the field as defined in SnapPlus or the SnapMaps website.
•Field County: The county where the field is drawn. This may not match a county specified in the Farm tab, preventing the field from being imported.
•Field Acres: The size of the field. This will match the data in SnapPlus if the field has not been drawn on the SnapMaps site.
•Soil Map Symbol (critical): The soil map symbol of the critical soil in SnapMaps. This will match the data in SnapPlus if the field has not been drawn on the SnapPlus site.
•Soil Map Symbol (predominant): The soil map symbol of the predominant soil in SnapMaps. This will match the data in SnapPlus if the field has not been drawn on the SnapPlus site.
•Slope: The slope of the field as defined by the soils in the field. This will match the data in SnapPlus if the field has not been drawn on the SnapPlus site.
•Slope Length: The slope length of the field as defined by the soils in the field. This will match the data in SnapPlus if the field has not been drawn on the SnapPlus site.
•Below Field Slope To Water: The average slope of the flow path from the field to the nearest surface water as estimated with the elevation of the field and the nearest surface water.
•Distance To Perennial Water: The down slope distance of the flow path from the field to perennial water as estimated using the nearest surface water at a lower elevation than the center of the field.,
•Is Locked: Check this box to indicate you do not want anything in this row to change upon future importations from SnapMaps. This is useful when you download new information from SnapMaps but do not want values of a certain field to be overridden by that information. After you Import to SnapPlus, all of the rows will have their Is Locked check box checked. Keep in mind, if you do want to change this information in the future, the Is Locked box will need to be unchecked for the importation of the new information to occur.
•Notes: Additional information about the field. This may be filled in by SnapPlus or by you.
•Field Borders: The geometry data for this field.
How the Distance To Perennial Water is Calculated
SnapMaps calculates the average elevation for a field. Then it measures from the centroid of the field to all water bodies within a certain distance and find the closest one that is downslope (at a lower elevation than the field). This is just a rough estimate but exact distances are not important for its use in the P Index Total P delivery ratio. For more information see p. 15 of the P Index calculation explanation document.