Irris Scheduler Help

Contents

Getting Started

The Irris Scheduler program estimates irrigation water needs and, optionally, soil nitrogen losses and availability. Before you can use the program, you will need to collect the following information for each field:

After this initial information has been entered, you only need to enter (or import) the following daily information beginning with your starting date: With this information, the program can then estimate how much irrigation water is needed and how soon it should be applied. If you let the program retrieve your field's soil data, it can also estimate soil nitrogen losses and availability (be sure to enter any nitrogen fertilizer applications as well - see below).

Operating the Program

The Irris Scheduler program consists of the following parts: Each field's data are saved in a separate data file with an .irr extension. When the program starts, it creates a new file automatically (indicated by [New File] on the title bar). You can enter data into this new file, or you can open and edit a data file that you named and saved during a previous session.

Tip: If you're new to the program, you can try it out by opening one of the sample data files that were installed along with the program.

When editing a data file, you'll only see one data entry panel at a time. To switch between panels, click on the tabs labeled Field, Crop & Soil and Weather & Irrigation.

Tip: Anytime you need help with what to enter or how to proceed, press the F1 key to display the program's on-line help. To display a list of help topics, click the Help button.

Entering Field, Crop & Soil Data

The Field, Crop & Soil panel contains several input boxes for entering data, as follows:

Farm Name

Enter a name that identifies your farm, such as "Smith Farms".

Field Name

Enter a name that identifies the specific field you will be irrigating, such as "North 40".

Location

Select the location for your field.

Coastal

Check this box if the field's location is strongly influenced by a large water body. The FAO definition of coastal is as follows: "Situated on or adjacent to the coast of a large land mass and where air masses are influenced by a nearby water body."

Metric Units

Check this box if the field's data are in metric units.

Latitude, Longitude

Enter the latitude of the field. Longitude is optional, but is also useful if you want to zoom to your field or retrieve forecast weather data.

If you want the program to be able to retrieve U.S. National Weather Service forecast data, you must enter both the latitude and longitude of the location that you want a forecast for. Enter the field's latitude and longitude as decimal degrees. For example, latitude of 40° 30' N would be entered as 40.5. Longitude of 87° 15' W would be entered as -87.25. Important! Be sure to enter a U.S. longitude as a negative number.

Tip: You can determine a field's latitude and longitude in a number of ways. For example, you can use a Web site like this one to zoom in to your crop field on the map, click the field, then copy and paste the latitude and longitude it displays into the Scheduler's Latitude and Longitude input boxes:

View Map

If you've entered the field's latitude and longitude and your computer is connected to the Internet, you can click the View Map button to launch your browser and zoom to the field's location on a map displayed by the "Clipper" Web app:

Tip: In addition to viewing a map of the field's location, you can also "clip" out the area displayed and download the aerial photograph and other files in a .zip file that can be imported into this free GIS:

Among other uses, if you draw in the field, you can let the GIS determine the field's soil(s).

Elevation

Enter the field's elevation. If you leave this blank, the program will use a value of 200 meters (approximately 650 feet) in its calculations.

Crop

Select the crop from the list. Important! Alfalfa must be an established crop (second year or older).

Emergence Date

Enter the date when at least 50% of the crop has emerged. Be sure to include the date's year (for example, 5/1/10). If the crop is replanted at a later date, be sure to change the emergence date.

Tip: For perennial crops like alfalfa, enter the green-up date when new leaves begin to grow.

Growing Season

Enter the average number of days from emergence to maturity for the crop. With crops that may be harvested before physiological maturity is reached, enter the standard length to maturity even if harvest may be scheduled early.

Tip: For perennial crops like alfalfa, enter the number of days from green-up to the last cutting.

Projected Yield

Enter a realistic yield goal based on the average of the previous five years for that field.

Rooting Depth

This may vary for different crop and soil combinations, but typical values are:

Minimum Moisture

Enter the minimum soil moisture content (%) in the root zone that you will permit before beginning to irrigate. Common values used are 50 to 60. Potato irrigators may want to maintain soil moisture at levels of at least 65%, particularly during critical periods of tuber initiation and bulking. On very sandy soils with low water holding capacity, it may be difficult to manage the irrigation system at very high levels because of the frequency with which irrigation water will be needed.

If you leave this blank, the program assumes 60% minimum moisture.

Previous Crop

Select the previous crop from the list.

Import Soil

To obtain soil survey data from the USDA-NRCS Soil Data Mart, click the Import Soil button. The program will display a list of soil surveys. Select a soil survey and the program will display a list of soils in the survey. Select the soil to use and the program will fill in the Soil Survey Symbol, Soil Map Unit Symbol, Soil Component Name, and Water Holding Capacity input boxes automatically.

Important! You must be connected to the Internet to use this feature. Also, you must use this feature in order for the program to estimate soil nitrogen losses and availability.

View Soil

Once you've retrieved soil data with Import Soil, you can view the soil horizon data by clicking the View Soil button.

Soil Survey Symbol

If you're unable to import Soil Data Mart data, you can manually enter a soil survey symbol. The survey symbol is a short identifier of 5 characters (for example, IN157).

Soil Map Unit Symbol

If you're unable to import Soil Data Mart data, you can manually enter the map unit for the predominant soil in your field. The map unit is a short (6 or fewer characters) identifier from the soil survey.

Soil Component Name

If you're unable to import Soil Data Mart data, you can manually enter the soil component name for the map unit. Most map units have only one major component. A soil complex will have more than one major component, so enter the one that best represents the field's soil.

Water Holding Capacity

If you're unable to import Soil Data Mart data (see Import Soil above), you will need to calculate water holding capacity using data from your local soil survey. Your local Natural Resources Conservation Service (NRCS) office can help with the calculations. Determine the best-drained soil covering the most acres in the field. In the soil survey table "Physical and Chemical Properties of the Soils," there will be a column labeled "available water capacity." Older soil surveys may have a table "Estimates of soil properties significant in engineering." Available water capacity (AWC) will be listed for each soil horizon as inches of water per inch of soil depth. Find the values that correspond to the soil type you have, then multiply by the rooting length in each horizon, as shown in the example below.

Example: Ormas loamy sand. Crop is corn, with 3 feet (36 inches) of rooting depth.

For this example, 3.68 inches would be entered for Water Holding Capacity.

Organic Matter

If you have an organic matter soil test, you can override the organic matter for the soil's surface horizon by entering it here. To see what the soil's organic matter is for the surface horizon, click the View Soil button.

Irrigation Efficiency

Enter the irrigation equipment's efficiency (%). For example, center pivot systems generally have an efficiency in the range 75-90%, meaning 75-90% of the water going into the system makes it to the crop root zone. Additional efficiencies are given here:

If you leave this blank, the program assumes 100% efficiency.

Notes

Enter any notes for your field or data.

Starting Moisture

Enter the estimated soil moisture content (%) in the root zone on the starting date. Average moisture content at emergence (or green-up with alfalfa) is often between 90% and 100%. If you're not sure what value to use, enter 100 if starting in spring or 50 if starting in fall.

Starting Residue

Enter the estimated residue cover (%) on the starting date. Note that you can change the residue later in the season, for example following a tillage event or if the residue has begun to decompose (see the Stage / Events column below).

If you leave this blank, the program assumes 0% residue cover.

Starting Date

Enter the starting date for the weather data. If you're only interested in irrigation scheduling, you can enter the same date that you entered for emergence above. However, if you also want the program to estimate soil nitrogen losses and availability, you should start at the beginning of the crop "water year". This is normally sometime soon after the harvest of the previous crop. In the northern hemisphere, October 1 is often used as the start of the water year. In any case, be sure to start before any nitrogen fertilizer applications.

Important! The weather data grid starts with the starting date. If you change the starting date once you've started entering weather data, the program will move the weather data up or down so that the new starting date is on the first row of the weather grid.

Calculation Date

Enter the date (typically today's date) for which you want to calculate a schedule. The program assumes the same year as emergence if you don't specify the year; with fall-seeded crops, be sure to include the year.

Calculate

Once you've entered your field information and weather data through the desired calculation date, click the Calculate button. The program checks to see that the data you've entered is valid; if there are no errors, it then calculates the schedule and displays it in the Preview Schedule window.

Entering Weather, Irrigation & Fertilizer Data

The Weather & Irrigation panel contains a grid where you enter daily high and low temperatures, wind speed, humidity, and precipitation and irrigation amounts. You can also right-click on the grid's Stage / Events column to enter events such as nitrogen fertilizer applications.

Each row of the grid corresponds to a different day in the schedule. The columns of the grid are as follows:

Day

This column contains the number of days since the starting date. The program considers the starting date as Day 1.

Date

This column contains the schedule's dates. The starting date is in the first row (Day 1).

Stage / Events

This column indicates the crop's growth stage for each day following emergence, as well as any events you might have entered (such as fertilizer applications). The four growth stages are Initial, Development, Mid-season and Late-season. By default the program estimates the date when each stage begins, but you can override the estimate by right-clicking in this column and choosing a stage from the popup menu to indicate that the stage begins on the currently selected row's date. For a fall-seeded crop like wheat, you can also choose Frozen or Snow-covered to indicate the start of winter periods when no crop transpiration occurs. When you override the default stage, the program displays an asterisk (*) after the stage as a reminder. You can delete an override and revert to the program's default by choosing Reset to Default for any stage that has an asterisk.

For more information about growth stages, see the discussion below.

Note that when you right-click on the Stage / Events column, you can also select events such as Fertilizer Application, Irrigation Water Nitrate, Manure Application, and Residue Cover from the popup menu to enter information about a nitrogen fertilizer application, irrigation water nitrate concentration, manure application, or change in residue cover.

Temp High, Temp Low

Enter the daily maximum and minimum temperatures in these columns. Try to take temperature readings at the same time each day. If possible, use a max-min thermometer. You can also use daily high-low temperatures reported in local newspapers.

Wind

Enter average wind speed if you have it. If you leave this value blank, the program will assume a wind speed of 2 meters per second (about 4.5 mph).

Humidity

Enter average relative humidity if you have it. Humidity is optional.

Precip

Enter any rainfall that the field received in this column. It's a good idea to install a rain gauge in each field, as rainfall amounts can vary widely in an area.

Note: If you don't enter a date's precipitation, the program assumes that no rain fell that day. It's a good idea to enter 0 if that's the case so you'll be able to distinguish between rainless days and days when you just forgot to enter anything. If you omit the decimal digits from 0, the days when rain fell (use 1 or 2 decimal digits) will be easy to spot.

Irrigation

Enter total irrigation for 24 hours in this column. If irrigation takes more than 24 hours, split the total irrigation amount between two days.

Notes

You can enter notes in this column about that day's weather or anything else you want to record.

Clear All

If you need to delete all of the weather data from the grid, click the Clear All button. This also deletes any growth stage overrides that you might have entered.

Import File, Import Clipboard, Import from Web

The Weather & Irrigation panel includes three import buttons below the weather input grid.

  1. Use the Import File button to import weather data from a file that you've downloaded from one of these sites. You can also use this button to import weather data from a different schedule data file (.irr), for example if you have more than one field with the same temperature data and you want to avoid entering the temperatures more than once.

    When you click the Import File button, the program displays the Select Weather Data File To Import dialog box, where you choose the downloaded file or schedule data file whose weather data you want to import. The program will then display the Import Weather Data dialog box, where you select what data you want to import. The program then reads the weather data from the file and assigns them to the current file's weather grid.

  2. Use the Import Clipboard button to import weather data that you copied to the clipboard from one of these sites.

    When you click the Import Clipboard button, the program displays the Import Weather Data Pasted From Clipboard dialog box, where you paste the data to import (click the Paste button, or right-click in the box and choose Paste, or press Ctrl+V).

  3. Use the Import from Web button to import weather data that the program retrieves automatically from the Web. For more information, see this topic.

    Caution! By default, when you import data, any temperature, wind speed, humidity and/or precipitation values for the selected dates in the current file's weather grid will be lost, replaced by the imported data. To prevent overwriting existing data, check the Fill In Only Missing Data box in the Import Weather Data dialog.

Growth stages

You can override the program's default growth stages by right-clicking on the Stage / Events column and choosing from the popup menu. The menu choices are as follows:

Retrieving Weather Data from the Web

Use the Import from Web button to import weather data that the program retrieves automatically from the Web.

Selecting a Web weather station

If you don't have a weather station or rain gauge near your field, you can import some or all of your weather data from an online Web source. However, deciding which Web weather station to use can be tricky. In most cases, a weather station close to your field will be more representative of the actual rainfall that fell on the field than a station farther away. But keep in mind that not all online weather data are useable and may contain missing or invalid data.

To see the distance and direction of each station from your field, make sure you've entered Latitude and Longitude on the Field, Crop & Soil panel. Note that station distance and direction may not be available for all Web sources.

Here are some steps you can follow in deciding on a station:

Using the Command Buttons

Below the data entry panels is a row of push buttons, as follows:

New

Click the New button to create a new, unnamed schedule data file. The program displays [New File] on the title bar and blanks the input boxes and weather input grid, then moves the cursor to the Farm Name input box, where you can begin entering your field information. To save the data and give the file a name, click the Save button.

Tip: When the program starts, it creates a new file automatically. You can enter data into this new file, or you can click the Open button to open and edit a data file that you named and saved during a previous session.

Open

Click the Open button to open an existing schedule data file. The program displays the Open Data File dialog box, where you choose the data file you want to open. The program reads the file's data and displays it in the data entry panels, where you can browse and edit the data.

Reopen

Click the Reopen button to open a recently opened data file. The program displays the Reopen Data File dialog box, where you select the data file you want to open from the list. The program reads the file's data and displays it in the data entry panels, where you can browse and edit the data.

Save

Click the Save button to save any changes you've made to the current file's data. If the file is new, the program displays the Save Data As dialog box, where you enter the name of the file to create for the data. If the current file already has a name (not a new file), the program just saves your data to the file without prompting.

Save As

Click the Save As button to save your file's data under a different name. The file's name appears in the File Name dialog box. Edit the name or enter a new name. Whenever you enter the name of a file that already exists, the program asks you to confirm this before overwriting the file's contents.

Options

Click the Options button to view and change the program settings. The program displays the Options dialog box.

Help

Click the Help button to display a list of help topics.

About

Click the About button to display the program version number and copyright information.

Exit

Click the Exit button to exit the program.

Viewing the Schedule

When you click the Calculate button, the program displays the Preview Schedule window (assuming there are no errors in your data). At the top of the window are several values that were calculated for your data, as follows:

Schedule Calculated For

Shows the result's calculation date. This is the date you entered in the Calculation Date input box.

Evapotranspiration Rate

This is the evapotranspiration rate for the calculation date.

Soil Profile Moisture Content

This is the estimated soil moisture content on the calculation date, based on soil water holding capacity, rooting depth, evapotranspiration, precipitation, and irrigation.

GDDs Since Emergence

This is the number of growing degrees days since crop emergence.

Water That Can Be Safely Added

This value is the amount of irrigation water that can be applied without excess runoff or leaching.

If No Rain, You Can Add 1 in. In

Assuming no precipitation, this is the number of days until the profile moisture content reaches the minimum value you specified (for example, 60%), at which time 1 inch of irrigation water is recommended.

Excess Water To Date

This value estimates the total amount of precipitation or irrigation water that could potentially run off the field or leach below the root zone.

Inefficiency Loss To Date

This is the portion of irrigation water that is assumed lost because of equipment inefficiency.


The Preview Schedule window also contains a preview grid containing the results of the daily calculations. You can view the daily calculations by scrolling the grid up and down. As in the weather input grid, each row in the preview grid corresponds to a different day in the schedule. Totals, averages, maximums and minimums are listed at the bottom of the table. The columns of the preview grid are as follows:

Day

This column contains the number of days since the starting date. The program considers the starting date as Day 1.

Date

This column contains the schedule's dates. The starting date is in the first row (Day 1).

Temp High, Temp Low

These columns contain the daily high-low temperatures you entered.

Precip

This column contains the daily rainfall amounts you entered.

Irrigation

This column contains the daily irrigation amounts you entered.

ET

This column shows the daily evapotranspiration rate. This is the estimated amount of water the soil is losing each day as a result of evaporation and crop transpiration.

Excess Water

This column shows the daily amount of excess water that has leached from the soil profile or run off the field.

Soil Mois

This column shows the daily soil moisture in the current rooting depth.

Soil Moisture (relative)

This column shows a simple graphic of the relative soil moisture content. Plus (+) signs indicate that soil moisture was above the desired minimum on that day; negative (-) signs indicate that the soil moisture was below the desired minimum on that day.

Avail. N

If you imported soil data from the Soil Data Mart using the Import Soil button (see above), this column will list the estimated amount of available nitrogen in the root zone that's available to the crop. If you did not import soil data, this column will be blank, as will the N Loss and N Uptake columns.

N Loss

This column lists the estimated amount of nitrogen lost due to denitrification or leaching below the root zone.

N Uptake

This column lists the estimated amount of nitrogen that has been taken up by the crop since emergence.

Note: Nitrogen uptake is not supported for all crops. With unsupported crops, the N Uptake column will be blank and the Avail. N column will overestimate available N after emergence since no reduction due to crop uptake has been made.


At the bottom of the Preview Schedule window are several push buttons, as follows:

Chart

Click the Chart button to export the schedule data to Excel and automatically generate charts using Excel. Note that this works best with later versions of Excel (for example, Excel 2010 or later).

Print

Click the Print button to print the schedule to your printer or to a text file.

Export

Click the Export button to output the schedule data to a CSV file that you can open with Excel and other programs. Note that the exported CSV file contains many more columns of data than are shown in the Preview Schedule window.

Close

Click the Close button to close the Preview Schedule window and return to the data entry part of the program.

Advanced Data Editing and Importing

As described in the topic Entering Weather, Irrigation & Fertilizer Data, you can obtain weather data to use for your field from several sources: The next two topics give some examples of additional sources of on-line weather data that you can enter or import into Scheduler.

If necessary, you can edit the soil data, as described in this topic:

Getting Weather Data from Other Sources

There are many on-line sources of weather data that you can also use in addition to the ones that Scheduler can retrieve automatically. For example, you could obtain rainfall data from the Community Collaborative Rain, Hail and Snow Network (CoCoRaHS). Point your Web browser at the following address: Here are brief instructions on how to use this site:
  1. Click the View Data link at the top of the page.
  2. Click the Daily Precipitation Reports link.
  3. Select your state and county.
  4. If you want data from a specific station, copy and paste the station number into the Station Fields box at the top, then check the Station Number box.
  5. Select the range of dates you want and click Search.

Your state may also host Web sites that you can use. For example, the Indiana State Climate Office maintains a Web site where you can interactively display recent data for the weather station nearest your farm. Point your Web browser at the following address: Here are brief instructions on how to use this site:
  1. Click the Data link at the top of the page.
  2. Select Daily - Purdue Automated.
  3. Enter a range of dates and click Continue.
  4. Select the station nearest your farm and click Run Report for Selected Stations. Do not select more than one station.
  5. Select English, Observations, Text view (Print friendly), then click Run Report for Selected Stations.
  6. Copy the data to the clipboard by choosing Edit | Select All, then Edit | Copy in your browser (or press Ctrl+A, Ctrl+C).
  7. To import the clipboard data, click the Import Clipboard button in the Scheduler.
Note: Tables of data from this site may not be complete for all requested dates.


If you have registered with the Midwest Regional Climate Center Web site, you can log in and request daily weather data from a number of different stations:

Importing Weather Data Manually

To import your own weather data:

  1. You can import a Comma Separated Values (CSV) text file that you create yourself. This file must include the following column headers in the first line. The order is not important as long as the data are in the same order as the headers. You can also include Wind Speed and Humidity if you have them. 
    Month,Day,Year,Precip,Max Temp,Min Temp
  2. Weather data starts on line 2, with one day of data per line. For example, a line of weather data might look like this for May 8, 2009, where 0.12 inch of rain fell and the high temperature was 80 and the low temperature was 52: 
    5,8,2009,0.12,80,52
  3. You can create this file with a text editor. You can also create it with Excel by saving your data as a CSV file.

  4. To import your data file, click the Import File button and select the CSV file.

    Tip: If you need to indicate the units for your data, you can also use these headers: 

    Month,Day,Year,Precip (inch),Max Temp (degF),Min Temp (degF),Wind Speed (mph),Humidity (%)
    Month,Day,Year,Precip (mm),Max Temp (degC),Min Temp (degC),Wind Speed (mps),Humidity (%)

To import data from Weather Underground:

  1. Point your Web browser at the following address:

  2. Enter the location you want in the box at the top of the page.

  3. Click the History tab.

  4. On the History tab, click the Custom tab.

  5. Select the range of dates you want and click Get History.

  6. Scroll down to the Observations table and click the Comma Delimited File button below the table.

  7. Once the weather data has been displayed, choose File | Save As in your browser and enter a name to use for the downloaded file (with a .txt file extension). Select Text File as the file type to save. Tip: Instead of downloading, you can copy the data to the clipboard by choosing Edit | Select All, then Edit | Copy in your browser (or press Ctrl+A, Ctrl+C).

  8. To import from a downloaded file, click the Import File button; to import from clipboard data, click the Import Clipboard button.

To import NEXRAD rainfall data:

  1. Point your Web browser at the following address:

  2. Using the map, zoom in on your farm or field, then click the location that you want NEXRAD rainfall data for.

  3. Select the starting and ending dates at the bottom of the page and click Submit.

  4. Once the rainfall data has been displayed, choose File | Save As in your browser and enter a name for the downloaded file (with a .txt file extension). Select Text File as the file type to save. Tip: Instead of downloading, you can copy the data to the clipboard by choosing Edit | Select All, then Edit | Copy in your browser (or press Ctrl+A, Ctrl+C).

  5. To import from a downloaded file, click the Import File button; to import from clipboard data, click the Import Clipboard button.

To import data from NOAA:

  1. Point your Web browser at the following address:

  2. Select your state and click Continue.

  3. Select the weather station closest to you and click Continue.

  4. Select the month to download and click Continue.

  5. Click the ASCII (CSV) button for Daily, then click the submit button.

  6. Once the weather data has been displayed, choose File | Save As in your browser and enter a name to use for the downloaded file (with a .txt file extension). Select Text File as the file type to save. Tip: Instead of downloading, you can copy the data to the clipboard by choosing Edit | Select All, then Edit | Copy in your browser (or press Ctrl+A, Ctrl+C).

  7. To import from a downloaded file, click the Import File button; to import from clipboard data, click the Import Clipboard button.

Editing Soil Horizon Data

For U.S. locations, you normally do not need to edit the soil horizon data at all. Just click the Import Soil button and let the program retrieve the soil horizon data automatically.

For non-U.S. locations, soil survey data are not available automatically to the program. In order for the program to estimate soil nitrogen losses and availability, you will need to enter data for all soil horizons to the crop's rooting depth. Click the View Soil button to view and edit soil horizon data. You can estimate the required soil properties using the references given in this document:

Note the soil horizon data are only required for estimating soil nitrogen. If you're only interested in irrigation scheduling, you only need to enter the soil's Water Holding Capacity to the crop's rooting depth, as described in Entering Field, Crop & Soil Data.

Notes for International Users

If you're irrigating fields that are not in the continental U.S., here are some tips for operating the program:

Location

Select a province (Canada) or country rather than a U.S. state. If your country is not listed, select the International location.

Metric Units

Normally you'll want to check this box.

View Map

With a non-U.S. location, the program uses Google Maps to zoom in on your field.

Import Soil

This button only works with U.S. soil survey data. To estimate your soil's water holding capacity, select a value from the following table (in mm/cm) and multiply it by your crop's rooting depth (in cm):

For example, with a uniformly loamy soil and a crop that has a rooting depth of 50 cm, enter 75 in the Water Holding Capacity box (1.50 x 50).

These values were adapted from the following source:

Tip: You can also enter soil horizon data and let the program calculate this for you. This data will also allow the program to estimate soil nitrogen losses and availability. See Editing Soil Horizon Data for more information.

Import from Web

U.S.-specific weather and forecast data choices are only available for U.S. locations. However, if your country is supported, you can select a Weather Underground airport station or Personal Weather Station. If you've registered your own station with the Weather Underground PWS network, you should see your station in the list. More information on the PWS network is here:

About the Authors

If you have agronomic questions, please contact:

If you have software questions, please contact:

Options

When you click the Options button, the program displays the Options dialog box, where you can change settings that affect how the program operates, as follows:

Popup Help Hints For Mouse Position, Display Help Hints On Status Bar

The program uses these two check boxes to determine what sort of help hints to display, as follows:

Last updated: March 22, 2017

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