- Author: Michael D Cahn
To set up a new ranch, click on the "new ranch" button at the bottom of the ranch list screen after logging on. You can also edit existing ranches that you previously set up by clicking on the ranch and selecting "edit ranch" from the menu. Note that you must be the "ranch owner" to edit the ranch.
Adding a new ranch or editing an existing ranch in CropManage has been made easier with the new online form under “add ranch,” which appears as an option on the left hand side of the screen (Fig 1). You can also still use the original method of filling out the downloadable spreadsheet template that can be selected on the right side of the menu.
CropManage uses information about your farm/ranch to develop recommendations on irrigation and N fertilizer management. Ranch data includes the main soil type and acreage of each field, well information, nearest CIMIS stations, commonly used fertilizers, and setting preferences for managing weather data and user access. By entering the information when the ranch is set up, the data is available for all plantings on the ranch, and does not need to be reentered when using CropManage for future irrigation and fertilizer decisions.
Fig. 1. Two options for adding a new ranch include using the online form or importing ranch information using the downloadable excel spreadsheet.
Step 1: Ranch Info Tab Add ranch name, ranch owner, and total acreage of ranch under the “info” tab (Fig. 2.) The ranch owner does not need to be the actual ranch owner. This should be the person that has the responsibility of managing the ranch information on CropManage and who will be responsible for granting access and permission to users. If you would like the ranch information to remain anonymous, then use a pseudonym for the ranch name and do not enter the ranch latitude and longitude coordinates. Keep in mind that ranch location information is need for importing spatial CIMIS reference evapotranspiration (ET) data.
Fig. 2. Information tab on the online ranch form.
Getting lat and long coordinates of a ranch If you will be using Spatial CIMIS, you must enter the ranch latitude and longitude coordinates. If you do not know the coordinates, then you can use a tool for locating the ranch by clicking in the ranch coordinates box (Fig. 3.) Using the Google map tool, you can zoom to the location of the ranch. Switch the display to satellite to see field boundaries. Click on the thumbtack in the upper left hand corner to activate coordinate selection, and then click on the map where the ranch is located. Choose save to import the lat. and long. coordinates into CropManage.
Fig. 3. Google map tool for selecting latitude and longitude coordinates of a ranch.
Step 2: Ranch Options Select the CIMIS weather and privacy options under the “options” tab (Fig. 4.) Choose if you want to get reference ET data directly from CIMIS weather stations or from Spatial CIMIS. Note that spatial CIMIS needs latitude and longitude coordinates of your ranch to function. Choose if you want to use CIMIS ET data from a particular weather station and set an order of preference for back up stations if data is not available from the first station (sequential mode) or average ET data from several stations.
The ranch owner can decide if latitude and longitude coordinates can be entered for the ranch by selecting in the coordinates option. By selecting” no coordinates entry” option no user with access to the ranch can enter latitude and longitude coordinates. This option will keep the location of the ranch anonymous. Again, Spatial CIMIS needs the location coordinates to function. If you choose the “no coordinate entry” option then you will need to choose a specific CIMIS station for the ET data.
Fig. 4. Options tab for selecting preferences for CIMIS weather data and privacy.
Step 3. Choose CIMIS stations The CIMIS stations tab (Fig. 5) is used to enter active CIMIS weather stations that will provide reference ET data for all plantings associated with the ranch. Even if you choose to use Spatial CIMIS, it is a good idea to enter the closest stations to the ranch in case spatial CIMIS data is not available or you want to change ET options at a future time. Use the “add station” button at the bottom left to see a list of all active CIMIS stations that are not currently associated with the ranch. You can sort the list by county or station number by selecting the list heading. After locating the station of interest, select the station number to add it to the ranch. Repeat this process for all stations . If you selected the sequential mode, the station at the top of the list will be the first station that CropManage uses for ET data to calculate the irrigation schedule. You can change the station preference order by selecting the arrows on the far right of the table (Fig. 5)
Fig. 5. CIMIS station tab for associating CIMIS weather stations with the ranch.
Step 4. Add field/lots to ranch Field or lot names are designated on the “Lot” tab (Fig. 6). Select “new lot” from the bottom left of the screen to enter a new field. Add a name and area (acres) of the field and then enter the soil type. If you do not know the soil type, then use the “find soil type” tool to the right of the form to determine the soil type of the lot. The tool links to the UC Davis SoilWeb using a google map application. Switch to satellite view to see field boundaries and click on the location of the field to obtain the soil properties needed for CropManage (Fig. 7.) A table will appear with the soil properties for the 1 and 2 foot depths (Fig 8.) By clicking on “Select this data,” you can associate the soil properties with the field. To save the soil properties, select OK in the window that appears asking to update soil properties. Be sure to click the “save lot” button on the bottom left of the screen before continuing.
Fig. 6. Lots/fields are added or edited in the “Lot” tab.
Fig. 7. Use the “Find Soil Type” tool to determine soil properties of the field.
Fig. 8. Soil property table is displayed after selecting the soil type using the Google map tool.
Step 5. Enter wells Using the “well” tab, well names and average salinity and nitrate concentration of the water can be added to the ranch (Fig. 9.) Although currently not available, we plan to add algorithms that determine the nitrogen contribution of the irrigation water to the crop and also determine an appropriate leaching fraction to apply to minimize salinity effects on the crop.
Fig. 9. The “Well” tab allows entry of ranch well information.
Step 6. Add/Edit users Using the “user” tab the ranch owner can determine which CropManage users can have access to their ranch and planting information and also set the level of access to the data (Fig. 10.) The ranch owner may decide that some users cannot have access to specific information, or can only view the data.
Fig. 10. The user tab allows the ranch owner to customize the level of permission for users.
Step 7. Add Fertilizers Customize a list of the commonly used fertilizers for the ranch in the “Fertilizer” tab by selecting “add” in the far right column (Fig. 11.) The selected fertilizers will display in a drop down menu when entering fertilizer events for the plantings. The database automatically converts between gallons or lbs of fertilizer to lbs of nitrogen using the conversions shown in the table. You can also enter fertilizers not shown on the tab using the “create fertilizer” button at the bottom left of the screen.
Fig. 11. A fertilizer list can be customized for a ranch under the “Fertilizers” tab.
Summary
Although setting up the ranch information requires some upfront investment of time, this base information eliminates the need to reenter data required later for calculating fertilizer N and irrigation recommendations. At anytime, ranch information can be edited or updated. If you are in a hurry, then just enter the minimal data needed. For example, you do not need to enter information for all fields on the ranch or add all the fertilizers to the fertilizer list. These can be added at a later time.
Now that the ranch information is updated, you are ready to start adding new plantings and using the soil test, fertilizer and irrigation functions of CropManage.
- Author: Michael D Cahn
- Author: Richard Smith
Understanding the nutrient value of nitrate in irrigation water often leads to confusion. Laboratories commonly report nitrate concentration of water samples in parts per million of nitrate (PPM NO3). However, as shown in Table 1, the reported nitrate value must be multiplied by 0.225 to express it in equivalents of nitrogen (PPM NO3-N). This conversion is required because the nitrate molecule has three oxygen atoms for every nitrogen atom, meaning that the nitrate molecule is 22.5% N by weight.
Several more calculations must be made to determine the pounds of N contained in a volume of water. Factors for converting PPM NO3 or PPM NO3-N to lbs of N per acre-foot (or acre-inch) are presented in Table 2. For example, multiplying a water test of 45 PPM NO3 by 0.62 would determine that an acre-foot of water contained about 28 lbs of N. If the same water test was reported as PPM Nitrate-N it would be equivalent to about 10 PPM N and would be multiplied by 2.72 to convert to lbs of N per acre-foot of water.
How much of the nitrogen in irrigation water should be credited as fertilizer value to a crop is debatable, especially for shallow rooted vegetables such as leafy greens. It is unclear if leafy green crops can make use of nitrate in irrigation water when concentrations are less than 20 ppm NO3-N. The soil nitrate level that optimizes lettuce growth is considered to be in the range of 15 to 25 ppm NO3-N. But this concentration is expressed in terms of weight of nitrogen per weight of soil (mg of N/kg of soil). Since soil is about 20% to 25% water by weight, the nitrate concentration in the soil water of most commercial lettuce fields would range between 60 to 120 ppm NO3-N. Field monitoring of nitrate concentration in soil water using suction lysimeter tubes installed in the root zone of lettuce has confirmed that most commercial fields are in the range of 50 to 150 ppm NO3-N, which is substantially higher than the concentration of nitrate found in most irrigation water.
Applying a leaching fraction to minimize the build-up of salt in the soil would also affect how to credit the fertilizer value of nitrate in irrigation water. Much of the nitrogen contained in the extra water applied to leach salts would presumably percolate beyond the root zone and not be available to the crop. In the Salinas Valley, growers report that ground water with a high nitrate concentration often has high levels of sodium and chloride salts. These water sources are often from shallow wells, where both salt and nitrate have leached over time into the aquifer. In these circumstances where elevated levels of salts are associated with high nitrate concentrations, a greater leaching fraction may be required and therefore less of the nitrate can be credited to the crop.
Irrigation efficiency can also factor into estimating the fertilizer value of nitrate in irrigation water. Fields with irrigation systems that apply water with poor uniformity would have areas where water drains below the root zone and other areas where less than the desired volume of water is applied.
Considering the above concerns, perhaps the fairest way to value nitrate in irrigation water is to take credit for the water that the crop uses for evapotranspiration (ET). This would be equivalent to the volume of water that enters the plant roots or evaporates from the soil surface leaving salts including nitrate behind. Lettuce transpires 5 to 8 inches of water between germination and maturity in the lower Salinas Valley during the summer. Factoring in irrigation system uniformity also makes sense. If the irrigation system uniformity is 80%, one may assume that 20% of the N in the applied water would likely percolate below the root zone and would not be available to the crop. For a crop that has a seasonal ET of 7 inches and an irrigation uniformity of 80%, the following values (Table 3) would approximate the N contribution of irrigation water for the indicated range of nitrate concentrations. Most wells in the Salinas Valley with elevated concentrations of nitrate are less 20 PPM NO3-N; therefore, we would expect that for most wells with this range of nitrate concentration, the irrigation water would contribute 20 to 30 lbs of N/Acre to a lettuce crop.
Conclusions
Growers have long been advised to reduce their standard nitrogen fertilizer rate if their irrigation water is high in nitrates. Extension publications commonly suggest that one can credit the nitrogen in irrigation water by multiplying the concentration of nitrate by the volume of water applied to a crop. As can be seen from the above estimates, water containing less than 45 ppm NO3 generally does not contribute a significant amount of nitrogen to crop growth (< 15 lbs N/acre). However, if well waters contain more than that amount, irrigation water may contribute greater amounts of nitrogen for crop production. In the future, we hope to conduct field trials to verify these estimates of the fertilizer value of nitrate in irrigation water.
Irrigation water is only one of several possible sources of nitrogen for a crop. The soil organic matter, added organic amendments, and previous crop residues continuingly mineralize releasing nitrogen. Fertilizer N is also periodically applied through sidedress and fertigation applications or as a slow release product. The good news is that you can account for the N contribution from the nitrate in the applied irrigation water as well as these other sources by using the quick nitrate soil test. However, keep in mind that this test only shows what has happened, and will not estimate the contribution of N from these sources, including irrigation water, to predict future crop N needs.
Table 1. Conversion factors between NO3 and NO3-N
Conversion between nitrate (NO3) and nitrate-nitrogen (NO3-N):
|
To convert |
To |
Multiply by |
|
Nitrate (NO3) |
Nitrate-nitrogen (NO3-N) |
0.225 |
|
Nitrate-nitrogen (NO3-N) |
Nitrate (NO3) |
4.43 |
Table 2. Factors for converting between nitrate concentration in irrigation water and pounds of N per volume of water.
Nitrogen content of irrigation water*
|
Water content of |
Multiply by |
To determine |
|
PPM NO3 |
0.052 |
Pounds N/acre inch |
|
PPM NO3 |
0.62 |
Pounds N/acre foot |
|
PPM NO3-N |
0.23 |
Pounds N/acre inch |
|
PPM NO3-N |
2.72 |
Pounds N/acre foot |
* water analyses from most labs report NO3 in units of ppm, but it is very important to pay attention to which units the results are reported.
Table 3. Estimated fertilizer N value of nitrate in irrigation water for lettuce production.
|
Nitrate (NO3) concentration in irrigation water |
Nitrate (NO3-N) concentration in irrigation water |
lbs nitrogen/acre in seven inches of irrigation water taken up by lettuce* |
|
45 |
10 |
13 |
|
89 |
20 |
25 |
|
177 |
40 |
51 |
|
266 |
60 |
76 |
* multiplied by 0.8 to account for the irrigation system efficiency
- Author: Michael D Cahn
CropManage Workshop
Monterey County Agricultural Center Conference Room
1432 Abbott St, Salinas CA 93901
Wednesday, March 13th / Tuesday, April 2nd 2013
(9 am – 11 am)
We will offer two hands-on workshops to learn in depth about the features of CropManage, a new Web-tool that provides decision support on irrigation and N management of lettuce. Learn how to use CropManage for improving the efficiency of your farming operations or for adding value to your consulting services. Wi-Fi internet access is available at our conference room so you are welcomed to bring a laptop or tablet computer so that you can follow along as we tour through the features of the software. There should be sufficient time to answer questions as we cover the following topics:
- Purpose and main features of software
- Getting started with CropManage (login, setting up new ranches, adding new plantings, fertilizers).
- Using CropManage for decision support and record keeping (soil nitrate quick test, recommendations on N fertilizer and irrigation schedules, maintaining fertilizer and irrigation records).
- Additional features (advanced settings, exporting data, integrating flow meter data).
- Discussion of new features or changes needed.
To keep the group size manageable so that we can provide individual help, we would like to limit each workshop to 20 participants. Please RSVP in advance by sending an email to larriaga@ucdavis.edu with the subject heading “CropManage workshop” and let us know which workshop (March 13 or April 2) you will be attending and the number of participants in your group. We will email you a confirmation
Hope to see you soon,
Michael Cahn
- Author: Michael D Cahn
Dear CropManage users,
UC Cooperative Extension, Monterey County will host an annual Irrigation and Nutrient Meeting in Salinas on Tuesday, February 26, between 7:45 am and 1:45 pm. The meeting will be held at the Agricultural Center at 1432 Abbott St, Salinas CA.
This meeting will be an opportunity to learn more about CropManage as well as research on irrigation and nutrient management of vegetables (see agenda below). We will serve a pizza lunch after the morning session and host a mini-workshop highlighting CropManage between 12:45 and 1:45 pm.
We hope to see you there.
Michael Cahn and Richard Smith
University of California Cooperative Extension, Monterey County
2013 Irrigation and Nutrient Management Meeting
Agricultural Center 1432 Abbott Street, Salinas, CA
Tuesday, February 26
7:45 a.m. to 1:45 p.m.
7:45 Registration and Refreshments
8:00 Salt water intrusion update Tamara Voss, Groundwater Hydrologist, Monterey County Water Resources Agency
8:30 Evaluating efficiency of irrigation systems Tom Lockhart, Staff Research Associate, UC Cooperative Extension, Monterey County
9:00 Introduction to CropManage: an online irrigation and nutrient management tool Mike Cahn, Irrigation and Water Resources Farm Advisor, Monterey County
9:30 ET-based irrigation scheduling of cool season vegetables Lee Johnson, Senior Research Scientist, CSUMB/NASA
10:00 Break
10:30 Strategies to remove nitrate and phosphate from tile and surface waters Tim Hartz, Vegetable Crops Specialist, UC Davis
11:00 Fertilizer technology evaluations and nitrogen uptake by vegetables Richard Smith, Vegetable Crops Farm Advisor, Monterey County
11:30 Soil and plant nutrition of potassium for vegetables Stuart Pettygrove, Extension Soils Specialist, UC Davis
12:00 Conclusion and Pizza Lunch
Afternoon Session:
12:45 Mini-workshop on CropManage and the quick nitrate soil test for improving nitrogen and water management of vegetables
Mike Cahn, Barry Farrara, and Richard Smith
1:45 Conclusion
* Sponsors: University of California Cooperative Extension; Resource Conservation District (RCD);
* Certified Crop Advisor Credits have been requested
* For more information call Richard Smith 759-7357 or Michael Cahn 759-7377
- Author: Michael D Cahn
Why online software? To help growers quickly make decisions on water and fertilizer management we developed CropManage to be fast, convenient, and easy to use. Our vision is that CropManage should be accessible from anywhere you work at anytime. You can use it in your truck from a smart phone, in the office from your desk top computer, or from home with your laptop or tablet computer. To achieve this flexibility we designed CropManage as an online application. Because the software is hosted on the internet you do not need to sync devices to update records, and multiple users can view and interact with the data. You are also free from the hassles of periodically updating the software on your computer.
Why use a database? CropManage can only provide accurate decision support on water and fertilizer management using specific information about your fields. This data includes properties of the soil, planting information, and characteristics of the irrigation system. To keep CropManage simple to use, data needed for future calculations are stored in a database. When you want an irrigation or fertilizer recommendation for any of your fields additional inputs of data are minimal because most of the required information is already loaded in the software. Because CropManage retains your data, you have access to your soil test, fertilizer, and irrigation records at anytime whether you are in the field or at the office. You can also export all of your data to your computer that can be viewed with a spreadsheet program such as Excel.
How do we keep your data private? Perhaps the biggest concern of an online tool is the security of the data. The University of California has a long-standing practice of keeping grower information confidential to the fullest extent possible under UC policy and California statute. We take this commitment seriously because we want to assure continued cooperation between growers and UC researchers.
We designed CropManage to maintain the privacy of all grower data. User access to ranch data is determined by a “virtual” ranch manager, who designates which users can view and edit data. This feature allows the grower to determine who can and cannot view and edit data. The “virtual” ranch manager can change user access and privileges at any time.
Another privacy concern is that your data will be available to other entities. Many commercial websites do collect data about their users which they may use for internal purposes or sell to outside entities. To the fullest extent allowable under UC policy and California statute your information will not be sold, exchanged, transferred, or given to any non-UC entity for any reason whatsoever, individually or in aggregate. However, it is possible that we may have to release your information if required by law.
As with all UC research projects, we will not analyze your data unless granted permission by the grower.
How do we protect your personal information? A minimal amount of personal information is needed to set up a login for access to CropManage (email address and name). Nevertheless, we implement a variety of security measures to maintain the safety of your personal information when you enter, submit, or access your personal information.
We use a secure server. All supplied sensitive information is transmitted via Secure Socket Layer (SSL) technology and then encrypted into our database to be only accessed by you, or UC personnel authorized with special access rights to our systems for development purposes.
All data is regularly backed up onto other servers so that any hardware failures will not cause a loss of information.
After deleting your account, your information will be removed completely, and unavailable to any entity including UC ANR.
Do we use cookies? We use cookies to help remember and process the data for your login information. No cookies are used to collect information related to your farming practices.
Can a user remain completely anonymous? Some users of this software may prefer to remain completely anonymous. The data cannot be traced back to a specific user or farm if names are changed and no spatial data are entered. CropManage uses longitude and latitude coordinates when Spatial CIMIS is selected for the source of evapotranspiration data.
In order to ensure your full privacy, these 3 steps can be taken:
- Use an anonymous email address when registering for this system.
- Do not enter your farm coordinates into the system. Choose the appropriate CIMIS stations manually.
- Do not enter the name of your farm or fields.
Summary
We designed CropManage to be simple and convenient to use by taking advantage of cloud computing. All precautions are and will be taken to assure that private data remains private and protected from outside entities. UC will not redistribute your data to outside entities to the fullest extent allowable under UC policy and California statute. At any point, you can export your data to your own computer, and you retain the option to completely remove your data from the CropManage database by deleting your account. Finally, you can use CropManage anonymously by not providing data that would identify the users and farming operation.
