Using SNMP as a GIS front-end for MMP

Introduction

Spatial Nutrient Management Planner (SNMP) is an ArcView-based program developed at the University of Missouri that can be used as a "front-end" for Purdue University's Manure Management Planner (MMP). With SNMP you can lay out an operation's fields and setback areas spatially and let its GIS automatically determine the following for each field:

Total field size
Setback area acres
Spreadable acres (total acres less any setback areas within a field)
Soil types

You can then export this data to MMP to complete a multi-year plan, allocate manure for all years of the plan, and generate reports.

SNMP can also generate a variety of color maps of the operation.

For more information on SNMP, go to the SNMP home page. If you already have SNMP installed and are ready to use it with MMP, be sure to review the SNMP tips.

SNMP requirements

Before you can use SNMP, you need to do four things:

Obtain or determine if you already have ESRI's ArcView 3.2.
Download and install the version of SNMP for your state.
Obtain the digital orthophoto quadrangles (DOQs) for the operation you'll be mapping.
Obtain the digitized soil layer for your county, if available (optional).

These steps are explained below.

1. Obtain ArcView 3.2

ArcView 3.2 is installed with the Customer Service Toolkit on many USDA-NRCS field office CCE computers.

Some state Extension office computers may already have ArcView installed as well.

ArcView is not cheap, so look around for educational or other discounts before purchasing it. If you want to try out ArcView before buying it, consider ordering the free ArcView 3.2 30-day evaluation CD from ESRI. Tip: Once you've received your evaluation copy and installed it, be sure to follow these instructions on how to install it properly.

2. Download and install SNMP for your state.

Versions of SNMP are currently available for these states:

Indiana
Missouri
Iowa
Michigan east and west
Ohio east and west
Oklahoma east and west
Wisconsin east and west
Tennessee east and west
Arkansas

To download a version of SNMP for your state, go to the SNMP home page.

Why are there two versions for some states? This is because these states fall into more than one Universal Transverse Mercator (UTM) zone. To determine which UTM zone your operation is in, refer to this map of Michigan, this map of Ohio, this map of Oklahoma, or this map of Wisconsin.

If your Michigan operation is in zone 16 (western and central Michigan), download SetupSNMP_MIw.exe; if your operation is in zone 17 (eastern Michigan), download SetupSNMP_MIe.exe.

If your Ohio operation is in zone 16 (western Ohio), download SetupSNMP_OHw.exe; if your operation is in zone 17 (central and eastern Ohio), download SetupSNMP_OHe.exe.

If your Oklahoma operation is in zone 14 (western and central Oklahoma), download SetupSNMP_OKw.exe; if your operation is in zone 15 (eastern Oklahoma), download SetupSNMP_OKe.exe.

If your Wisconsin operation is in zone 15 (western Wisconsin), download SetupSNMP_WIw.exe; if your operation is in zone 16 (eastern Wisconsin), download SetupSNMP_WIe.exe.

Note: Iowa also falls into two UTM zones. However, since all but a few westernmost counties are in the same zone, there is only one version of SNMP for Iowa at this time. To determine if you can use the Iowa version of SNMP with your operation, refer to this map of Iowa. If your operation is in zone 15 (almost all of Iowa), you can download SetupSNMP_IA.exe; if your operation is in zone 14, you'll have to wait for a future version of SNMP.

Tip: You can install more than one version of SNMP on the same computer. The Missouri version is currently the only one that includes an example operation. If you want to look at a sample operation before laying out your own operation, download and install the Missouri version. Be sure to install it in a different folder than your state's version.

3. Obtain the DOQs for your operation.

Digital orthophoto quadrangles (DOQs) are aerial photos used in SNMP for locating farms and drawing field and setback boundaries.

Most counties encompass several quadrangles. Each quadrangle is divided into four quadrants or quarters. Each quadrant, commonly called a DOQ (although technically a DOQQ), covers an area measuring 3.75 minutes of longitude by 3.75 minutes of latitude, or roughly 5 miles on a side. You will need to obtain one or more DOQ for your operation. Sometimes an operation fits within the same DOQ, in which case you will only need to obtain a single DOQ. But often an operation straddles two or more DOQs, in which case you will need to obtain more than one DOQ.

You can order DOQs in high-quality GeoTIFF format from USGS for a nominal fee. Refer to the detailed instructions on ordering from the USGS Web site. These DOQs can be ordered on CD-ROM or for downloading. However, DOQ files in GeoTIFF format are quite large (40-45 MB) and you should not attempt to download them over a phone modem.

SNMP can also use DOQs in other formats, which can be obtained from the following sources:

In Indiana, there are two ways you can obtain DOQs:

You can order CD's of DOQs in MrSID format for $15 per CD from the Purdue University Media Distribution Center. Refer to the ordering instructions.
You can go to the Indiana University Indiana Geographic Data site and download free DOQs in MrSID or BSQ format, as follows:
- Click the IN DOQQs Download link.
- Click a city near the area where you need DOQs.
- Click a closer city.
- Click the most recent year.
- Click the bsq or mrsid link.
- You'll now see a list of DOQs by name.
  - With mrsid files, click to download the .tar archive file. Once downloaded, extract the .tar file's .sid and .sdw files with WinZip.
  - With bsq files, click to download the .bsq file you need and its associated .hdr file.
  Note: If you're working over a phone modem, select the mrsid files. The .bsq files are very large (40-45 MB each); do not attempt to download .bsq files over a phone modem.
- If you can't find the DOQs you need, try an earlier year.

In Missouri, you can go to the University of Missouri Map Room Web site and use the Interactive Maps applet to cut out just the piece of the DOQs that you need. This piece will be much smaller and easier to download than one or more entire DOQs.

In Iowa, you can go to the Iowa State Iowa Geographic Image Map Server site and zoom in on a piece of a DOQ for downloading at 2-meter resolution (USGS DOQs are at a higher 1-meter resolution).

In all states, you can go to the SNMP site and click the Get Data link to use a Web-based program to view and zoom in on the aerial photo you need and clip out and download the area of your farm.

After obtaining the DOQ files, copy them to the DOQ folder under the main SNMP folder. When creating a new operation with SNMP, use the Add/Remove Photo tool (on the View Tools menu) to add one or more DOQs to your county map so you can zoom in and draw the farm boundaries. When SNMP asks you for the location of a DOQ, navigate to the DOQ folder where you copied them and select the file that SNMP is looking for.

4. Obtain the digitized soil layer for your county (optional).

A soil layer is a digitized version of your county's soil survey map. This soil layer allows SNMP to determine each field's soil type automatically. If you don't have your county's soil layer, you can still use SNMP, but it won't be able to determine soil types when you draw in your fields.

In Indiana, you can download the soil layer files for any SSURGO-certified county in Indiana if you have a high-speed Internet connection.

In Missouri, when you cut out and download a piece of a DOQ, you can also download the soil layer for that piece.

In other states, you will either need to locate a source for your county's soil layer or create the soil files yourself.

In general, soil layers can only be created for counties whose soil survey maps have been digitized and certified for the national Soil Survey Geographic (SSURGO) database. To check the status of this digitizing effort, refer to the SSURGO status map of the U.S. For a complete list of certified counties, go to the SSURGO Web site.

If you decide to create the soil layer files yourself, be sure to refer to the detailed instructions.

Last updated: May 23, 2002