Context: Table 1. Example corn yield loss estimates when stress occurs for four or more consecutive days. Adapted from Classen and Shaw, 1970; Rhoads and Bennet, 1990; and Shaw, 1988.  The Corn Development stage known as early vegetative (VE - V12) has an estimated Yield Loss per Day of Stress of 1-3. The Corn Development stage known as Late vegetative (V12 to VT) has an Estimated Yield Loss per Day of Stress of 2-5. The Corn Development stage known as Pollination to Blister (R2) has an Estimated Yield Loss per Day of Stress of 3-9. The Corn Development stage known as Milk (R3) has an Estimated Yield Loss per Day of Stress of 3-6. The Corn Development stage known as Dough (R4) has an Estimated Yield Loss per Day of Stress of 3-5. The Corn Development stage known as Dent (R5) has an Estimated Yield Loss per Day of Stress of 2-4. The Corn Development stage known as Maturity (R6) has an Estimated Yield Loss per Day of Stress of 0.

Question: What is the estimated yield loss per day of stress for corn in the pollination to blister development stage?

Answer: 3-9

Licht, M., & Archontoulis, S. (2017). Influence of Drought on Corn and Soybean | Integrated Crop Management. https://crops.extension.iastate.edu/cropnews/2017/07/influence-drought-corn-and-soybean


Context: The inherent risk of injecting fertilizer into a water system dictates the need for backflow protection. Both Indiana and Michigan have resource protection rules that require the use of Chemigation valves for the protection of both surface and ground water sources. Chemigation valves create an air gap in the pipe line downstream from the pump when the pump is shut down. The air gap breaks the suction created by water retreat back to groundwater or surface water. Chemigation valves for most irrigation application are available from local irrigation dealers for less than $700. Installation cost is much less at the time of pump installation and should be included in almost all new irrigation pumping installations.

Question: What does the airgap created by the chemigation gaps do?

Answer: breaks the suction created by water retreat back to groundwater or surface water.

Kelley, L. (2013). Irrigation Fact Sheet #12 - Nitrogen Application with Irrigation. https://www.canr.msu.edu/uploads/235/67987/FactSheets/12_NitrogenApplicationWithIrrigationFact_Sheet.pdf


Context: The registration process also calls for an estimate of consumptive water use. Consumptive water use is the amount of water that is lost from the area of withdrawal. Since most water pumped for crop irrigation ultimately goes into evapotransporation, the consumptive use is estimated to be high or about 90%. Water used for harvest cooling is mostly retuned back to surface or groundwater so the consumptive use is estimated to be low or about 5 to 10%.

Question: What is considered to be a high consumptive water use?

Answer: 90%

Kelley, L. (2007). Irrigation Fact Sheet #4 - Michigan Registration for New Agricultural Withdrawals. https://www.canr.msu.edu/uploads/235/67987/lyndon/MIRegNewAgWith.pdf


Question: What is the short hand for the milk development stage of corn?

Answer: R3

Licht, M., & Archontoulis, S. (2017). Influence of Drought on Corn and Soybean | Integrated Crop Management. https://crops.extension.iastate.edu/cropnews/2017/07/influence-drought-corn-and-soybean


Context: Instructions for completing the Evaluating Potential Irrigation Runoff Form. (4) Center pivots'Starting at the pivot point and progressing to the furthest reaches of the machine, pace or measure 50-foot increments along that line to identify observation points, or identify three equally spaced observation points under each span. Solid set or travelers'Start at one edge of the wetted area and progress to the opposite side, pace or measure 50-foot increments along that line to identify observation points.

Question: Where should I end when it comes to completing the Evaluating Potential Irrigation Runoff Form for solid set systems?

Answer: progress to the opposite side

Kelley, L. (2014b). Irrigation Fact Sheet #13 - Reducing and Evaluating Irrigation Runoff. https://www.canr.msu.edu/uploads/236/43605/FactSheets/13_ReducingAndEvaluatingIrrigationRunoff_5-9-14.pdf


Context: Estimating water use can be accomplished by several methods: (a) Water application multiplied by number of applications, plus estimate of additional water use. (b) Pump capacity multiplied by run time or fuel/power use per hour. (c) Flow meters actual flow, note maintenance and calibration concerns. (d) Industry average numbers (Mid West Plan Service or ASAE) with appropriate adjustments (not appropriate for high variable water uses such as irrigation).

Question: Where can I look to find industry average numbers that are used to estimate water usage?

Answer: Mid West Plan Service or ASAE

Kelley, L. (2022). Irrigation Fact Sheet #11- Checklist for Planning Irrigation Systems. https://www.canr.msu.edu/irrigation/upoads/files/11ChecklistForPlanningIrrigationSystems08.22.pdf


Context: Question: What does it cost to setup a new quarter-section center pivot? Excerpt: Irrigation wells tap aquifers and unfortunately, most aquifers in North Dakota contain some level of dissolved iron. The amount of iron may vary from low to high but its presence in the water leaves a rusty color on pumps, pipelines and irrigation systems. The iron in the water provides the energy that iron bacteria need to grow and that process leaves a slimy organic substance on well screens, pump intakes and other parts of the well. It only takes a few years for this organic substance to plug the well screen and reduce well production. The only way to control iron bacteria is by annual chlorination.

Question: What causes the rusty color on pumps, pipelines, and irrigation systems?

Answer: iron

NDSU Agriculture. (2024). Irrigation - Frequently Asked Questions. https://www.ndsu.edu/agriculture/ag-hub/ag-topics/crop-production/irrigation-tiling-drainage/irrigation-frequently-asked-questions


Context: The Water Withdrawal Assessment Tool (WWAT) is designed to estimate the likely impact of a water withdrawal on nearby streams and rivers. Use of the WWAT is required of anyone proposing to make a new or increased large quantity withdrawal from the waters of the state, including all groundwater and surface water sources, prior to beginning the withdrawal. You must use the WWAT to determine if a proposed withdrawal is likely to cause an Adverse Resource Impact, and to register the withdrawal. The results page provides a quick link to submitting a registration. A registration is valid for 18 months; the withdrawal capacity must be installed within that 18 months or the registration becomes void.

Question: What tools are there water withdrawal sites?

Answer: The Water Withdrawal Assessment Tool (WWAT)

EGLE. (2023). WWAT-Home Page. https://www.egle.state.mi.us/wwat/(S(whxx1bja4grx05ino0gubkx4))/default.aspx


Context: At times of peak water use, the application volume could be as large as 1.5 inches for four to five days of water use. It is all about efficiency. The plant most effectively uses water is through transpiration. Water that is lost from evaporation at the soil surface or on the leaves is less beneficial to the plant, providing only a temporarily cooler environment. Small application may help in evaporative cooling during pollination or other crucial times, but reduces the amount of water that actually gets to the roots compared to fewer large applications totaling the same amount.

Question: What is the application volume at peak water use?

Answer: as large as 1.5 inches for four to five days of water use

Kelley, L. (2014c). Irrigation Fact Sheet #14  - Irrigation Application Volumes. https://www.canr.msu.edu/uploads/235/67987/FactSheets/14_IrrigationApplication.pdf


Context: (13) Service center drive and final drives on pivots. Gearboxes should be checked annually. First drain condensation water from the bottom of the box and then refill with recommended gear lube.

Question: What else should you check when inspecting and repairing your irrigation system?

Answer: Gearboxes should be checked annually.

Kelley, L. (2017). Irrigation Fact Sheet #15 - Irrigation Inspection and Repair. https://www.canr.msu.edu/uploads/235/67987/factsheets/15_Irriation_Inspection_and_Repair_v2_4.21.17.pdf


Question: What are chemigation valves for?

Answer: create an air gap in the pipe line downstream from the pump when the pump is shut down

Kelley, L. (2013). Irrigation Fact Sheet #12 - Nitrogen Application with Irrigation. https://www.canr.msu.edu/uploads/235/67987/FactSheets/12_NitrogenApplicationWithIrrigationFact_Sheet.pdf


Question: When can small applications help when it comes to irrigation?

Answer: in evaporative cooling during pollination or other crucial time

Kelley, L. (2014c). Irrigation Fact Sheet #14  - Irrigation Application Volumes. https://www.canr.msu.edu/uploads/235/67987/FactSheets/14_IrrigationApplication.pdf


Context: (2b) Withdrawals planned in the next 18 months can also be registered in Michigan's Water Withdrawal Assessment Tool if the withdrawal receives a favorable assessment. By law beginning February 28, 2006, a person shall not make a new or increased large quantity withdrawal that causes an adverse resource impact. A person who knowingly makes a new or increased large quantity withdrawal that causes an adverse resource impact may be subject to a civil fine of not more than $10,000.00 per day of violation. Falsifying a record submitted in this process may result in a civil fine of not more than $1000.

Question: What is the civil fine that a person receives after knowingly causing an adverse resource impact with a water withdrawal?

Answer: not more than $10,000.00 per day of violation

Kelley, L. (2009c). Irrigation Fact Sheet #9 - Michigan Large Volume Water Use Requirements. https://www.canr.msu.edu/uploads/235/67987/lyndon/9largewaterwith.pdf


Context: Irrigation systems need to be able to replace the typical water use of the plant during a prolonged dry period. System costs increase as capacity increases. Typically water sources capable of 400 to 1200 gallons per minute are used to supply irrigation water. Systems designed to apply 0.25 inch per day (5 gallons/minute/acre of irrigation) can provide adequate water in all but the most extreme situations. Evapotransporation rate (E.T.) is a term that represents the daily water lost by the plants maintenance and growth along with the evaporative loss from the soil surface. E.T. rates for almost all crops grown in northern Indiana and Michigan have rates under 0.25 inch per day for all but a few extreme days.

Question: When should irrigation systems be able to replace typical water use of a plant?

Answer: during a prolonged dry period

Kelley, L. (2007b). Irrigation Fact Sheet #5 - Estimating Annual Irrigation Costs. https://www.canr.msu.edu/uploads/235/67987/irrigation_costs/5_Estimating_Annual_Irrigation_Costs.pdf


Context: A simple, inexpensive catch can stand can be built using: 1. 32 oz. disposable soda cup (Taco Bell cup) 2. 3 inch plastic drain pipe cut to 5 inch in length 3. 2 x 3 inch stud, cut to length to wedge into plastic drain pipe (drill hole partially through the chunk of wood to accommodate the fence post) 4. Steel (step-in) electric fence post

Question: How many 3 inches studs do you need to build a catch can stand?

Answer: 2

Kelley, L. (2020). Irrigation Fact Sheet #16 - Catch Can Stands for Rain Gauges and Uniformity Check for Evaluating Irrigation.


Question: What is the procedure for completing the Evaluating Potential Irrigation Runoff Form for traveler systems?

Answer: Start at one edge of the wetted area and progress to the opposite side, pace or measure 50-foot increments along that line to identify observation points

Kelley, L. (2014b). Irrigation Fact Sheet #13 - Reducing and Evaluating Irrigation Runoff. https://www.canr.msu.edu/uploads/236/43605/FactSheets/13_ReducingAndEvaluatingIrrigationRunoff_5-9-14.pdf


Context: Calculating the amount to raise the rent if the landowner invests in the well and other permanent land improvements is a common question. In most situations the landowner wants to get more for the investment in the well then annual estimated cost of the investment in the well (DIRTI formula). Calculation of the annual cost of ownership of an investment is often represented by the DIRTI (Depreciation, Interest, Repairs, Taxes, and Insurance) formula which spreads the actual cost of ownership of an equipment investment over its usable lifespan or investment period. A standard procedure is outlined on page 7 of MSU Extension Bulletin E-2131, "Custom Work Rates in Michigan". This formula will provide you with the annual cost of the original investment in equipment and improvements

Question: What does the DIRTI formula do?

Answer: spreads the actual cost of ownership of an equipment investment over its usable lifespan or investment period

Kelley, L., Miller, S., & Loudon, T. (2006). Irrigation Fact Sheet #1- Agricultural Water Use Reporting for 2006 Changes in Water Use Regulation. https://www.canr.msu.edu/uploads/235/67987/FactSheets/1_AgWaterUseReporting11-29-06.pdf


Context: (5) Irrigation Scheduler: is a simple computerized irrigation scheduling checkbook model from the Agronomy Department of Purdue University. This method can be used throughout Michigan and Indiana. Crop specific E.T. values are estimated using the daily high and low temperatures and rainfall provided by the producer or weather data can be imported from the internet.

Question: How are crop specific E.T. values estimated?

Answer: using the daily high and low temperatures

Kelley, L. (2009a). Irrigation Fact Sheet #6 - Irrigation Aspects of Land Lease Agreements. https://www.canr.msu.edu/uploads/235/67987/lyndon/LandRent.pdf


Question: How many different materials or equipments do you need to build a simple, inexpensive catch can stand?

Answer: 4

Kelley, L. (2020). Irrigation Fact Sheet #16 - Catch Can Stands for Rain Gauges and Uniformity Check for Evaluating Irrigation.


Context: (13) Match your farming/family goals to your irrigation ideas. If you think you have a difficult time getting away for a summer vacation now, adding irrigation will greatly increase the required summer labor and cut free time. Capable irrigation labor is hard to find. Misjudging your available labor and management time needs towards completing irrigation can lead to a disaster. Good irrigation planning can set your direction for a profitable and efficient irrigation future.

Question: Is finding irrigation labor easy?

Answer: hard to find

Kelley, L. (2022). Irrigation Fact Sheet #11- Checklist for Planning Irrigation Systems. https://www.canr.msu.edu/irrigation/upoads/files/11ChecklistForPlanningIrrigationSystems08.22.pdf


Question: What is the Irrigation Scheduler tool?

Answer: a simple computerized irrigation scheduling checkbook model

Kelley, L. (2009a). Irrigation Fact Sheet #6 - Irrigation Aspects of Land Lease Agreements. https://www.canr.msu.edu/uploads/235/67987/lyndon/LandRent.pdf


Context: Drought symptoms in corn: Corn leaf rolling is the primary symptom of drought. Greying of leaf tissue will occur under extremely severe conditions. The earlier leaf rolling occurs in the day or the longer the duration of leaf rolling the greater the stress the crop is under. Yield loss estimates are assumed when drought stress occurs for four consecutive days or more.

Question: What does a longer duration of leaf rolling mean?

Answer: the greater the stress the crop is under

Licht, M., & Archontoulis, S. (2017). Influence of Drought on Corn and Soybean | Integrated Crop Management. https://crops.extension.iastate.edu/cropnews/2017/07/influence-drought-corn-and-soybean


Context: An overview of procedure to establish new large volume withdrawals: (a) Determine needed pumping capacity and probable location for the new withdrawal. (b) Work through the Michigan Large Volume Water Withdrawal Assessment Tool (MiWWAT) for a determination. (c) If the MiWWAT assessment is green (zone A) or yellow (zone B) you can proceed to register your proposed water withdrawal. Building can happen in the following 18 months and any small modification can be noted by returning to the tool and modifying your original request.

Question: How can I indicate any small modifications to my large volume withdrawal?

Answer: by returning to the tool and modifying your original request.

Kelley, L. (2009c). Irrigation Fact Sheet #9 - Michigan Large Volume Water Use Requirements. https://www.canr.msu.edu/uploads/235/67987/lyndon/9largewaterwith.pdf


Context: Irrigation systems need to be able to replace the typical water use of the plant during a prolonged dry period. System costs increase as capacity increases. Typically water sources capable of 400 to 1200 gallons per minute are used to supply irrigation water.Systems designed to apply 0.25 inch per day (5 gallons/minute/acre of irrigation) can provide adequate water in all but the most extreme situations.

Question: What is 0.25 inch per day in gallons/minute/acre?

Answer: 5 gallons/minute/acre of irrigation

Kelley, L. (2007b). Irrigation Fact Sheet #5 - Estimating Annual Irrigation Costs. https://www.canr.msu.edu/uploads/235/67987/irrigation_costs/5_Estimating_Annual_Irrigation_Costs.pdf


Context: (9) Get multiple bids. Use irrigation professionals to your advantage. Take your best ideas to at least two irrigation sales/design people. Many will have access to excellent mapping and planning software tools, plus they will have far more experience than most producers in irrigation system design. Compare potential designs on a cost per irrigated acre basis (for an average years irrigation). This process will help equalize investment in equipment with energy cost and labor.

Question: How can I equalize investment in equipment with energy cost and labor?

Answer: Compare potential designs on a cost per irrigated acre basis

Kelley, L. (2011). New irrigation planning checklist - MSU Extension. https://www.canr.msu.edu/news/new_irrigation_planning_checklist


Context: Effects on pollinating corn: Drought stress 7-10 days ahead of silking can result in delayed silk development. When combined with heat stress this delay could result in poor anthesis silking interval (ASI). Water stress during pollination (tasseling through silking) not only delays silking, but also reduces silk elongation, and if severe, impedes embryo development. With temperatures greater than 95oF, low humidity, and low soil moisture level, silks will desiccate or become non-receptive to pollen. Pollen grains may also be damaged from desiccation when they are released for tassel anthers. When temperatures greater than 100oF , pollen grains are killed. Drought stress during pollination ultimately results in poor pollination and fewer kernels per ear.

Question: What can cause delayed silk development?

Answer: Drought stress 7-10 days ahead of silking

Licht, M., & Archontoulis, S. (2017). Influence of Drought on Corn and Soybean | Integrated Crop Management. https://crops.extension.iastate.edu/cropnews/2017/07/influence-drought-corn-and-soybean


Context: Yes, especially if the plants are healthy and irrigation can begin at pod initiation. In general, the most important time to irrigate soybeans is from R3 (beginning pod, one pod 3/16 inch long on one of the upper four nodes on the main stem having unrolled leaves) through R6 (full seed, one pod containing green seed that fills the pod cavity on one of the upper four nodes on the main stem having unrolled leaves).

Question: What is the irrigation period for soybeans?

Answer: from R3

Staton, M., & Kelley, L. (2012). Answers to common questions about irrigating soybeans - MSU Extension. https://www.canr.msu.edu/news/answers_to_common_questions_about_irrigating_soybeans


Context: Late season applications are lowered as crop water use declines with increasing crop maturity. At the dent stage of development, corn water use can be as little as 0.15 inches per day on a 75 degree day. The chance of receiving rainfall increases during this portion of the growing season. Applications of 0.75 inches at the beginning of this period may quickly decline to 0.50 inch as the crop nears black layer or maturity.

Question: Are late season applications lowered or highered?

Answer: lowered

Kelley, L. (2013a). Efficient irrigation application volumes change throughout crop development. https://www.canr.msu.edu/news/efficient_irrigation_application_volumes_change_throughout_crop_development


Context: Water is extremely important for crop production. When water becomes limiting to the plant it is important to understand how plants use water. We often hear the term evapotranspiration (ET) in relation to plant water demand. ET is a combination of soil water evaporation (E) and water used by the plant during transpiration (T). Soil evaporation is the major loss of water surface and typically is higher after rain and under high temperature conditions.

Question: What is essential to crop production?

Answer: Water

Licht, M., & Archontoulis, S. (2017). Influence of Drought on Corn and Soybean | Integrated Crop Management. https://crops.extension.iastate.edu/cropnews/2017/07/influence-drought-corn-and-soybean


Context: Applying nitrogen fertilizer or crop protection products through a center pivot is an efficient and effective method. In fact, it is a well-documented best management practice to apply nitrogen fertilizer as close to the time the corn will use it to get the most efficient use of the fertilizer. Most of the products are injected into the pivot with a fixed rate injection pump. So, how does one figure the pumping rate to set the pump at, and what about the change the end gun causes when it's turned on and off? We will discuss both challenges in this article.

Question: How are most products injected into the pivot?

Answer: with a fixed rate injection pump

Melvin, S. (2023a). How to Determine the Chemigation Injection Pump Setting for a Center Pivot with the End Gun Off and On. UNL CropWatch. https://cropwatch.unl.edu/2023/how-determine-chemigation-injection-pump-setting-center-pivot-end-gun-and


Context: Annual operating costs will include an estimate of energy cost and labor attributable to the average operation of the equipment. For calculation purposes an annual use of six 1 inch applications of irrigation was used. A greater number of small applications will favor systems that have low labor costs, where a smaller number of large applications would favor systems with high labor and low investment attributes. Systems with low energy cost primarily from low pumping cost are favored by higher total annual use where low initial cost often compensate for higher energy cost if a low total volume of water is applied annually.

Question: What kind of systems are favored by a higher total annual use?

Answer: Systems with low energy cost primarily from low pumping cost

Kelley, L. (2014a). Irrigation Fact Sheet #7- Reducing and Evaluating Irrigation Runoff.Instantaneous irrigation application rates compared to soil infiltration rates. https://www.canr.msu.edu/uploads/235/67987/FactSheets/7_ReducingAndEvalRunoff.pdf


Context: (3) On and after July 9, 2009 ' Large quantity water withdrawals proposed after July 8, 2009 must receive a favorable assessment from 'Michigan's Water Withdrawal Assessment Tool' or an approval from a requested site-specific review by the MDEQ and be registered before proceeding. If a site-specific review by the MDEQ or an evaluation by the Water Withdrawal Assessment Tool determines that a proposed withdrawal is a zone A or a zone B withdrawal, there is a rebuttable presumption that the withdrawal, as specified in the review or tool, will not cause an adverse resource impact. As previously stated penalties are in place for causing an adverse resource impact.

Question: What would prompt a rebuttable presumption that the withdrawal will not cause an adverse resource impact?

Answer: a proposed withdrawal is a zone A or a zone B withdrawal

Kelley, L. (2007b). Irrigation Fact Sheet #4 - Michigan Registration for New Agricultural Withdrawals. https://www.canr.msu.edu/uploads/235/67987/lyndon/MIRegNewAgWith.pdf


Context: How to Get More Out of Your Irrigation System: (6) Get maximum effectiveness of soil applied herbicide. Irrigate with 0.5 inch or more to activate herbicide within 48 hours if rain is not expected.

Question: How much water should I irrigate with to activate herbicide?

Answer: 0.5 inch or more

Kelley, L. (2009b). Irrigation Fact Sheet #8 - How to Get More from your Irrigation System. https://www.canr.msu.edu/uploads/235/67987/lyndon/HGMIrrSys.pdf


Context: In extreme situations of average daily temperatures over 90 degrees, low relative humidity and wind, water use may reach .31 to .33 inches per day. Crops that cannot tolerate extremes may need an irrigation system designed to meet a requirement of one inch every 3 days (6.5 gallons/minute/acre of irrigation). System design capacity of greater than 6.5 gallons/minute/acre of irrigation are only needed in situation where crop management practice result in water application at a rate faster than the soil infiltration rate resulting in water loss below the root zone or less than 100% effective water use.

Question: What is the minimum water use rate that may occur during extreme situations?

Answer: .31

Kelley, L. (2007b). Irrigation Fact Sheet #5 - Estimating Annual Irrigation Costs. https://www.canr.msu.edu/uploads/235/67987/irrigation_costs/5_Estimating_Annual_Irrigation_Costs.pdf


Question: Where can the standard procedure of calculating the DIRTI formula be found?

Answer: page 7 of MSU Extension Bulletin E-2131, "Custom Work Rates in Michigan".

Kelley, L., Miller, S., & Loudon, T. (2006). Irrigation Fact Sheet #1- Agricultural Water Use Reporting for 2006 Changes in Water Use Regulation. https://www.canr.msu.edu/uploads/235/67987/FactSheets/1_AgWaterUseReporting11-29-06.pdf


Question: What happens to corn under extremely severe conditions?

Answer: Greying of leaf tissue

Licht, M., & Archontoulis, S. (2017). Influence of Drought on Corn and Soybean | Integrated Crop Management. https://crops.extension.iastate.edu/cropnews/2017/07/influence-drought-corn-and-soybean


Context: Insurance coverage: Establish responsibility for insurance coverage for the well, other permanent irrigation related improvements along with insurance coverage for the pivots and other non-permanent irrigation related equipment is an issue to be resolve before the insurance is needed. The local farm insurance provider in the area can help you evaluate the irrigation related options available. Many irrigation dealers can also direct you toward specialized irrigation insurance coverage.

Question: How can irrigation dealers help me in regards to insurance?

Answer: direct you toward specialized irrigation insurance coverage

Kelley, L., Miller, S., & Loudon, T. (2006). Irrigation Fact Sheet #1- Agricultural Water Use Reporting for 2006 Changes in Water Use Regulation. https://www.canr.msu.edu/uploads/235/67987/FactSheets/1_AgWaterUseReporting11-29-06.pdf


Context: (1) Enviroweather: computes daily estimate of potential E.T. and projects E.T. demands for 7 days at each of the 58 strategically located weather stations in Michigan calculating crop E.T. using wind, relative humidity, and net solar radiation in addition to temperature to estimate crop E.T. demands. Pick the station nearest to you, and then click on one of the categories listed near the top of the screen (eg. Field crops, Fruit), then click on Potential Evapotranspiration. For corn and soybeans clicking the Crop ET Estimate button then entering the emergences date allowing tracking crop ET as the crop develops. A free service of Enviroweather Network sends daily reports of ET from the previous 4 days and projected values for the next week by text or E-mail to producers that signed up.

Question: In Enviroweather, what is the first step for tracking crop ET as the crop develops?

Answer: clicking the Crop ET Estimate button

Kelley, L., & Miller, S. (2019). Irrigation Fact Sheet #3 - Irrigation Scheduling Tools. https://www.canr.msu.edu/uploads/236/43605/FactSheets/3_IrrigationSchedulingTools5.14.pdf


Context: Question: What about different soil types? Excerpt: The soil is a storage room of the plants nutrients, and the medium, through which water and nutrients move. It is the anchor for plants and the reservoir of water for plants' growth. There are various types of soil with differing characteristics, which determine What types of plants can be grown. Nevertheless, plants can thrive in a very broad spectrum of soil textures when water is applied at the proper rate, with appropriate spacing.Each type of soil creates a typical wetting pattern that will require a different layout. In sandy soil, the water will tend to go straight down, so we recommend using micro sprinklers or closely spaced, 12 in. apart, 1 GPH or 2 GPH drippers. In loamy soil, the water will move slowly and will spread evenly, so here you can use .5 GPH or 1 GPH drippers with a 16 in. to 18 in. spacing. In clay soil in which drip irrigation work the best, the water will be absorbed very slowly, so use low flow drippers such as .5 or 1 GPH at a wider spacing, 18 in. to 24 in. apart.

Question: How should I set up my system in sandy soil?

Answer: using micro sprinklers or closely spaced, 12 in. apart, 1 GPH or 2 GPH drippers

Sunn, L. (2023). Drip Irrigation | Rainwater. https://www.rainbees.com/drip-irrigation


Context: Question: What is the maximum flow that I can use with a single line of ' in. drip tubing, single line of ' in. micro tubing or a single line of 1/8 in. micro tubing? Excerpt: You should not exceed more than 220 GPH on a single line of 1/2 in. poly tubing with .700 OD, 35 GPH on a single 1/4 in. micro tubing with .245 OD or 5 GPH on a single 1/8 in. microtubing with .187 OD.

Question: What is the maximum flow that I can use on a single line of 1/2 in. poly tubing with .700 OD?

Answer: 220 GPH

DIG Corp. (2024). Drip Irrigation FAQ’s. https://www.digcorp.com/drip-irrigation-faqs/


Context: (10) Cornering arm hydro valves: Use of hydro valves is the most common method for controlling the irrigation water from individual sprinklers on cornering arms and Z arms that are in their folded back position. If valves are stuck open you are grossly overwatering endrows or other field edges where the arm is not deployed. Valves that are stuck closed will result in under watering corners of the field. While the machine is running, inspect sprinklers in a corner area with the arm fully deployed to make sure all sprinklers come on and in an area with the arm fully folded to see if all valves shut off.

Question: In what state should the hydro arms be when ensuring that all valves are shut off?

Answer: fully folded

Kelley, L. (2017). Irrigation Fact Sheet #15 - Irrigation Inspection and Repair. https://www.canr.msu.edu/uploads/235/67987/factsheets/15_Irriation_Inspection_and_Repair_v2_4.21.17.pdf


Question: How often can E.T. reports be retrieved from the Enviroweather Network?

Answer: daily

Kelley, L., & Miller, S. (2019). Irrigation Fact Sheet #3 - Irrigation Scheduling Tools. https://www.canr.msu.edu/uploads/236/43605/FactSheets/3_IrrigationSchedulingTools5.14.pdf


Context: (6) Rock traps, screens and filters - Remove debris, sand and small stones from rock traps. Clean screens and filters often used in conjunction with end guns and cornering arms. Rock traps are often removed for the winter to prevent freeze damage from water condensation in pipe and accumulating in trap. If rock traps were removed for the winter and bird guards are not put in place inspect openings for nests.

Question: What are the steps when it comes to dealing with rock traps, screens and filters?

Answer: Remove debris, sand and small stones from rock traps

Kelley, L. (2017). Irrigation Fact Sheet #15 - Irrigation Inspection and Repair. https://www.canr.msu.edu/uploads/235/67987/factsheets/15_Irriation_Inspection_and_Repair_v2_4.21.17.pdf


Context: Irrigation systems need to be able to replace the typical water use of the plant during a prolonged dry period. System costs increase as capacity increases. Typically water sources capable of 400 to 1200 gallons per minute are used to supply irrigation water. Systems designed to apply 0.25 inch per day (5 gallons/minute/acre of irrigation) can provide adequate water in all but the most extreme situations. Evapotransporation rate (E.T.) is a term that represents the daily water lost by the plants maintenance and growth along with the evaporative loss from the soil surface. E.T. rates for almost all crops grown in northern Indiana and Michigan have rates under 0.25 inch per day for all but a few extreme days.

Question: In what states do most crops have an E.T. rate of under 0.25 inch per day, with the exception of a few extreme days?

Answer: in northern Indiana and Michigan

Kelley, L. (2007b). Irrigation Fact Sheet #5 - Estimating Annual Irrigation Costs. https://www.canr.msu.edu/uploads/235/67987/irrigation_costs/5_Estimating_Annual_Irrigation_Costs.pdf


Context: Question: Why should we use drip irrigation? Excerpt: Drip irrigation applies water and nutrients very efficiently directly to the plant's roots and only where it is needed ensuring healthy plants and vigorous growth. Studies on drip irrigation systems are show results of up to 60% more efficiency over sprinkler systems.

Question: What does drip irrigation ensure?

Answer: healthy plants and vigorous growth

DIG Corp. (2024). Drip Irrigation FAQ’s. https://www.digcorp.com/drip-irrigation-faqs/


Context: Assembly directions - Option 1: The 2 x 3 inch stud chunks wedge into the base of the cut plastic drain pipe sections, and make the transition between the cup and post. Electric fence post should fit snug into the drill hole. A screw may be placed through the side of the plastic drain pipe into the 2 x 3 inch stud chunks. Electric fence post and cups can be stored and transported in separate stacks.

Question: When building a catch can test, how should you handle the electric fence post and cups?

Answer: Electric fence post and cups can be stored and transported in separate stacks.

Kelley, L. (2020). Irrigation Fact Sheet #16 - Catch Can Stands for Rain Gauges and Uniformity Check for Evaluating Irrigation.


Context: Several factors can lead to low distribution equipment costs which can be achieved with the right combination of the following: (a) Total size of irrigated areas - the bigger the system the lower the cost (b) Shape of the irrigated areas - 160 acre squares are hard to beat (c) Three phase electric power is readily available near control panels (d) Flat topography - hills and slopes require shorter pivot spans to maintain crop clearance.

Question: What kind of topography is ideal to achieve low distribution equipment cost?

Answer: hills and slopes require shorter pivot spans to maintain crop clearanc

Kelley, L. (2007b). Irrigation Fact Sheet #5 - Estimating Annual Irrigation Costs. https://www.canr.msu.edu/uploads/235/67987/irrigation_costs/5_Estimating_Annual_Irrigation_Costs.pdf


Context: Even when the lessee provides all off the irrigation equipment and the water supply, rent value should be expected to be higher than local dry land rent prices. Land rent prices for irrigated ground are often higher than the cost of installing irrigation spread over a seven or ten year schedule. In most situations the additional profit for establishing irrigation on rental property is evident or the lessee would not be seeking to proceed. This opportunity cost for irrigation may be as small as 10% of the rent value or as great as 200% added to local dry land rent values. The prevalence of high dollar irrigated specialty crops are a major factor in the variability.

Question: Does it make a difference whether the lessee provides all the equipment and water supply?

Answer: rent value should be expected to be higher than local dry land rent prices

Kelley, L. (2009a). Irrigation Fact Sheet #6 - Irrigation Aspects of Land Lease Agreements. https://www.canr.msu.edu/uploads/235/67987/lyndon/LandRent.pdf


Context: As July nears, irrigation goals need to switch to maximizing water to the root zone. Potential to loose water below the root zone lessens with higher crop water use and less chance of potential rain fall meeting crop needs. Transpiration is more effective use of water than evaporation from soil or leaf surface, providing an opportunity for irrigators to maximize effective water use by minimizing the time they wet the plant leaf and soil surface. Limiting the number of time the foliage is wetted also reduces the potential for many foliar crop diseases.

Question: Does the potential to lose water below the root zone increase or decrease in July?

Answer: lessens

Kelley, L. (2013a). Efficient irrigation application volumes change throughout crop development. https://www.canr.msu.edu/news/efficient_irrigation_application_volumes_change_throughout_crop_development


Context: Table 1. Example corn yield loss estimates when stress occurs for four or more consecutive days. Adapted from Classen and Shaw, 1970; Rhoads and Bennet, 1990; and Shaw, 1988.  The Corn Development stage known as early vegetative (VE - V12) has an estimated Yield Loss per Day of Stress of 1-3. The Corn Development stage known as Late vegetative (V12 to VT) has an Estimated Yield Loss per Day of Stress of 2-5. The Corn Development stage known as Pollination to Blister (R2) has an Estimated Yield Loss per Day of Stress of 3-9. The Corn Development stage known as Milk (R3) has an Estimated Yield Loss per Day of Stress of 3-6. The Corn Development stage known as Dough (R4) has an Estimated Yield Loss per Day of Stress of 3-5. The Corn Development stage known as Dent (R5) has an Estimated Yield Loss per Day of Stress of 2-4. The Corn Development stage known as Maturity (R6) has an Estimated Yield Loss per Day of Stress of 0.

Question: What is the R6 development stage of corn called?

Answer: Maturity

Licht, M., & Archontoulis, S. (2017). Influence of Drought on Corn and Soybean | Integrated Crop Management. https://crops.extension.iastate.edu/cropnews/2017/07/influence-drought-corn-and-soybean


Context: How to Get More Out of Your Irrigation System: (7) Reduce nitrogen fertilizer loss to volatilization. Water in nitrogen application with  0.5 inch or more of irrigation water to move nitrogen into the soil.

Question: What does nitrogen application do?

Answer: to move nitrogen into the soil.

Kelley, L. (2009b). Irrigation Fact Sheet #8 - How to Get More from your Irrigation System. https://www.canr.msu.edu/uploads/235/67987/lyndon/HGMIrrSys.pdf


Context: Option to purchase the farm in future: (c) Repayment requirements of the unrecouped portion of the permanent land improvements made by the lessee if contract is prematurely terminated is often view as a form of security from farm land being sold out from their ability to lease. A schedule of repayment is constructed by amortizing the dollar investment over the period of the contract at the current interest rate. The resulting chart allows the landowner to find the agreed upon fee for early termination of the contract. Contract needs to have provisions for early termination upon one of agreed list if situations happen. These may include death of one of the parties, sale of farm or dissolving of the farm business.

Question: What does a payment schedule allow for?

Answer: allows the landowner to find the agreed upon fee for early termination of the contract

Specht, J., & Torrion, J. (2015). Optimize Your Irrigation Application Timing with SoyWater.unl.edu | CropWatch | University of Nebraska–Lincoln. https://cropwatch.unl.edu/optimize-your-irrigation-application-timing-soywaterunledu


Context: (5) Water registration. Irrigation water use almost always is considered a large volume water use (capacity to pump > 70 gal./min). In both Indiana and Michigan new installations require a registration. In Indiana this is handled by Indiana DNR. In Michigan you will need to work through the Michigan Water Withdrawal Assessment Tool to determine if your proposed water use is likely to cause a negative environmental impact. At the end of the process you will either be able to register online or may be required to request a site specific review by MDEQ. MDEQ site specific reviews may result in allocation of the water resulting in registration or the opportunity to bring together all large volume water users in the watershed to negotiate reducing use by existing water users to allow allocations for a new water use.

Question: What are the options after using the Michigan Water Withdrawal Assessment Tool?

Answer: to register online or may be required to request a site specific review by MDEQ

Kelley, L. (2022). Irrigation Fact Sheet #11- Checklist for Planning Irrigation Systems. https://www.canr.msu.edu/irrigation/upoads/files/11ChecklistForPlanningIrrigationSystems08


Context: Yes, especially if the plants are healthy and irrigation can begin at pod initiation. In general, the most important time to irrigate soybeans is from R3 (beginning pod, one pod 3/16 inch long on one of the upper four nodes on the main stem having unrolled leaves) through R6 (full seed, one pod containing green seed that fills the pod cavity on one of the upper four nodes on the main stem having unrolled leaves).

Question: When to start irrigating soybeans?

Answer: at pod initiation.

Staton, M., & Kelley, L. (2012). Answers to common questions about irrigating soybeans - MSU Extension. https://www.canr.msu.edu/news/answers_to_common_questions_about_irrigating_soybeans


Context: Estimating Annual Irrigation Costs. Annual irrigation cost can be divided into two categories: annual cost of ownership and the annual cost of operation - mainly the cost of energy and labor. The annual cost of ownership is often estimated by the DIRTI (Depreciation, Interest, Repairs, Taxes, and Insurance) formula which spreads the actual cost of ownership of an equipment investment over its usable lifespan or investment period. A standard procedure is outlined on page 7 of MSU Extension Bulletin E-2131, "Custom Work Rates in Michigan". This formula can provide you with the annual cost of the original investment in equipment and improvements.

Question: What does the D stand for in DIRTI?

Answer: Depreciation

Kelley, L. (2007b). Irrigation Fact Sheet #5 - Estimating Annual Irrigation Costs. https://www.canr.msu.edu/uploads/235/67987/irrigation_costs/5_Estimating_Annual_Irrigation_Costs.pdf


Context: Fertigation is often the last step in a three split nitrogen management plan, following starter and side dress applications. Starter allows quick access to nutrients to the newly germinated plants. Side dress applications usually account for the greatest portion of N budget, feeding the plant just prior to the rapid growth phase. Depending upon the equipment used, side-dressing can also aerate soil and improve water infiltration. Fertigation makes up the remainder of the budget supplying nitrogen to the crop just prior to tassel emergence. For efficient use, Nitrogen applications need to be made prior to tasseling to ensure that the nitrogen applied is in an available form for the plant to uptake and use during early grain formation.

Question: What do side dress applications account for?

Answer: the greatest portion of N budget, feeding the plant just prior to the rapid growth phase

Kelley, L. (2011). New irrigation planning checklist - MSU Extension. https://www.canr.msu.edu/news/new_irrigation_planning_checklist


Context: Permanent improvements. A repayment schedule may be included in the agreement for the recovery of investment dollars not recouped if early termination of the agreement is required. An annual cost of permanent improvements to the land needed for irrigation can be found by amortizing the dollar investment over the period of the contract at the current interest rate. The annual cost may be added to the dry land rent rate plus an additional opportunity cost representing the added income opportunity with irrigation to compensate landowner for permanent improvements to the land needed for irrigation.

Question: What is the additional opportunity cost associated with permanent improvements made to land which is to be irrigated?

Answer: the added income opportunity with irrigation

Kelley, L. (2009a). Irrigation Fact Sheet #6 - Irrigation Aspects of Land Lease Agreements. https://www.canr.msu.edu/uploads/235/67987/lyndon/LandRent.pdf


Context: Checkbook method of irrigation scheduling follows the concept that the soil in your field is like a bank checking account. Rainfall and irrigation applications are deposits into the checking account. Rainfall and irrigation may need to be reduced to reflect the effective amount added to soil moisture. Daily water removal from evaporation and transpiration (evapotranspiration or E.T.) from the field and crop would be considered withdrawals from the account. Soil has a maximum amount of water that can be held (called Field Capacity), so water added beyond the soils water holding capacity is lost to the account. Irrigation applied at a rate exceeding the infiltration capacity will cause surface runoff and be lost to the soil water balance account.

Question: What is considered to be a deposit into a checking account?

Answer: irrigation applications

Kelley, L. (2009a). Irrigation Fact Sheet #6 - Irrigation Aspects of Land Lease Agreements. https://www.canr.msu.edu/uploads/235/67987/lyndon/LandRent.pdf


Context: Land rent pricing: Establishment of irrigated rental value is relatively straight forward when all of the irrigation equipment and water supply is the landowners. Average current rent value is available from State and Federal Agricultural Statistic Services or your Agricultural Economics Department from your States Extension service. Talking to neighbors that rent irrigated land is one of the best ways to get a feel for irrigated rental value. Land rent auction can also be used to establish rent value but a solid structure for the process is necessary.

Question: What can land rent auction be used for?

Answer: to establish rent value

Kelley, L., Miller, S., & Loudon, T. (2006). Irrigation Fact Sheet #1- Agricultural Water Use Reporting for 2006 Changes in Water Use Regulation. https://www.canr.msu.edu/uploads/235/67987/FactSheets/1_AgWaterUseReporting11-29-06.pdf


Question: How can the annual cost of permanent improvements to the land needed for irrigation be found?

Answer: by amortizing the dollar investment over the period of the contract at the current interest rate.

Kelley, L. (2009a). Irrigation Fact Sheet #6 - Irrigation Aspects of Land Lease Agreements. https://www.canr.msu.edu/uploads/235/67987/lyndon/LandRent.pdf


Context: (8) Power sources. Identify available power sources - a 3 phase power line in close proximity (1/2 mile or less) to potential water sources is the cheapest. Liquid fuel storages located near wells and surface water pose potential environmental risks, along with higher equipment, maintenance and fuel cost, leaving engine power as a second choice for most situations.

Question: How close should the power sources be located relative to potential water sources?

Answer: 1/2 mile or less

Kelley, L. (2010). Irrigation Fact Sheet #10 - Shared Irrigation Expenses. https://www.canr.msu.edu/uploads/235/67987/lyndon/10_Shared_Irrigation.pdf


Context: An estimate of expected water use by the month is needed. Most irrigators will estimate their water use from experience multiplied by the number of acres irrigated. As an example: 100 acres with 1.5 inches of irrigation applied in June would have an estimated water use of 150 acre inches for the month. Three inches of estimated irrigation need in both July and August and 1 inch in September would give us an estimated annual water use of 550 acre inches for the year.

Question: What estimation is needed when registering for new agricultural withdrawals in Michigan?

Answer: expected water use by the month

Kelley, L. (2007). Irrigation Fact Sheet #4 - Michigan Registration for New Agricultural Withdrawals. https://www.canr.msu.edu/uploads/235/67987/lyndon/MIRegNewAgWith.pdf


Context: Maximum economic yield with minimum amount of irrigation is a goal for most irrigators. Efficient irrigation water use means providing enough water to avoid drought stress, but not so much that water is lost out of the rooting zone or to runoff from the surface. This includes leaving enough water holding capacity to capture the next normal rainfall thus not losing the value of rainfall and also reduce the risk of leaching and run-off. In the irrigated region of northern Indiana and Michigan evaporate losses during irrigation application are minimal due to high humidity. The humid condition cause several differences in irrigation management for efficiency compared to the arid west.

Question: Why should I leave enough water holding capacity?

Answer: to capture the next normal rainfall thus not losing the value of rainfall and also reduce the risk of leaching and run-off

Kelley, L. (2014c). Irrigation Fact Sheet #14  - Irrigation Application Volumes. https://www.canr.msu.edu/uploads/235/67987/FactSheets/14_IrrigationApplication.pdf


Question: Why is transpiration important when it comes to irrigation?

Answer: is more effective use of water than evaporation from soil or leaf surface, providing an opportunity for irrigators to maximize effective water use by minimizing the time they wet the plant leaf and soil surface.

Kelley, L. (2013a). Efficient irrigation application volumes change throughout crop development. https://www.canr.msu.edu/news/efficient_irrigation_application_volumes_change_throughout_crop_development


Context: Effects on corn during grain fill: During grain fill drought stress results in premature death of leaf tissue, shortened grain fill periods, increased lodging, fewer kernels, and light kernel weights. Kernel abortion near the ear tip will occur in the two weeks following pollination. Continued drought into the milk stage will result in further kernel abortion and smaller, lighter kernels. Drought that occurs in the mid to late grain filling period (milk, dough, and dent stages) results in decreased kernel weights and premature physiological maturity. Once physiological maturity occurs additional drought stress will have no impact on grain yield. Because drought stress typically coincides with higher than normal temperatures the grain fill period is often reduced.

Question: What is the result of drought that occurs in the milk, dough, and dent stages?

Answer: decreased kernel weights and premature physiological maturity

Licht, M., & Archontoulis, S. (2017). Influence of Drought on Corn and Soybean | Integrated Crop Management. https://crops.extension.iastate.edu/cropnews/2017/07/influence-drought-corn-and-soybean


Context: Act PA 148 established state-wide groundwater mapping and water use reporting. This law created a groundwater resource map of the state and establishes a groundwater advisory committee to direct groundwater protection efforts in the future. The MDA will assemble township-based reports annually and forward them to the MDEQ.

Question: Where does the MDA forward township based reports?

Answer: to the MDEQ

Kelley, L. (2009c). Irrigation Fact Sheet #9 - Michigan Large Volume Water Use Requirements. https://www.canr.msu.edu/uploads/235/67987/lyndon/9largewaterwith.pdf


Context: P.A. 33 of 2006 amended Michigan's Natural Resources Protection Act as part 327 of 451. Changes included:  (c) Requirement for new agricultural withdrawals: Both new wells and surface water withdrawal capable of 100000 gallon per day (70 gpm) are now required to register with Michigan Department of Agriculture prior to beginning to pump. Forms are available at the same locations as the reporting forms. You will need to provide the latitude and longitude for the location, an estimate of expected water use by the month and an estimate of the volume of consumptive use of the water pumped. Since most water pumped for irrigation ultimately goes to the evapotransporation of the crop the consumptive use is estimated to be high or about 90%. Water use for harvest cooling is mostly retuned back to surface or groundwater so the consumptive use is estimated to be low about 5 to 10%.

Question: Where does most water pumped for irrigation go?

Answer: to the evapotransporation of the crop

Kelley, L., Miller, S., & Loudon, T. (2006). Irrigation Fact Sheet #1- Agricultural Water Use Reporting for 2006 Changes in Water Use Regulation. https://www.canr.msu.edu/uploads/235/67987/FactSheets/1_AgWaterUseReporting11-29-06.pdf


Context: Infiltration rate is the quantity of water that can enter the soil in a specified time interval. Heavier soils such as clay and clay loam take water in at a slower rate than sands and sandy loams. Tillage method and surface compaction affect infiltration rate. Conservation tillage and no-till result in the highest infiltration rates while disc and moldboard tillage result in the lowest rates, particularly after several wetting events. Michigan soils have infiltration rates from as slow as one-half inch per hour to as fast as three inches per hour. Estimates for water infiltration rates are included in the Physical and Chemical Properties of Soils section of the soil survey for each county.

Question: What does tillage method have an affect on?

Answer: infiltration rate

Kelley, L. (2014). Irrigation Fact Sheet #7- Reducing and Evaluating Irrigation Runoff.Instantaneous irrigation application rates compared to soil infiltration rates. https://www.canr.msu.edu/uploads/235/67987/FactSheets/7_ReducingAndEvalRunoff.pdf


Context: Question: How you can tell that the system is working? Excerpt: There are several ways to verify that your drip irrigation system is working:Check for moisture or wetted area at the surface of the soil directly below a dripper and around the base of the plant .If the drippers are subsurface connect micro tubing to the dripline at any location (ideally at the end of the line) and raise it to the surface. At the end of the microtubing installed a dripper and use it as a point source dripper to check if the system is operating.Monitor the flow at your water meter.Check the control valve via the manual external bleed.

Question: Where should I check for moisture or wetted area?

Answer: at the surface of the soil directly below a dripper and around the base of the plant

DIG Corp. (2024). Drip Irrigation FAQ’s. https://www.digcorp.com/drip-irrigation-faqs/


Question: What do new irrigation installations require in Michigan?

Answer: require a registration

Kelley, L. (2022). Irrigation Fact Sheet #11- Checklist for Planning Irrigation Systems. https://www.canr.msu.edu/irrigation/upoads/files/11ChecklistForPlanningIrrigationSystems08


Context: P.A. 33 of 2006 amended Michigan's Natural Resources Protection Act as part 327 of 451. Changes included: (f) Reporting of static water level is no longer required: Static water level reporting was moved from a requirement to report.

Question: What was static water level reporting changed to?

Answer: from a requirement to report

Kelley, L., Miller, S., & Loudon, T. (2006). Irrigation Fact Sheet #1- Agricultural Water Use Reporting for 2006 Changes in Water Use Regulation. https://www.canr.msu.edu/uploads/235/67987/FactSheets/1_AgWaterUseReporting11-29-06.pdf


Context: Increasing the amount of water that may enter the soil in a given period of time: The total application of water will also affect the fraction of the water that may enter the soil in a given time period. Small pockets and depressions in the soil surface will hold a volume of water at that location, until the soil surface can receive the water. Midseason cultivation or in-row soil surface modification (dammer/dikers) will increase the soils surface holding capacities.

Question: In what location in the soil is water stored?

Answer: depressions in the soil surface

Kelley, L. (2014a). Irrigation Fact Sheet #7- Reducing and Evaluating Irrigation Runoff.Instantaneous irrigation application rates compared to soil infiltration rates. https://www.canr.msu.edu/uploads/235/67987/FactSheets/7_ReducingAndEvalRunoff.pdf


Context: Plant transpiration increases as corn leaf area increases. Transpiration is the mechanism by which water moves from the soil through the plant into the atmosphere. The greatest water demand for corn occurs from the late vegetative stages through the blister stage and for soybean from the early pod set through the mid seed fill stages. In other words, the greatest demand for transpiration occurs during periods of rapid growth.

Question: What happens as corn leaf area increases?

Answer: Plant transpiration increases

Licht, M., & Archontoulis, S. (2017). Influence of Drought on Corn and Soybean | Integrated Crop Management. https://crops.extension.iastate.edu/cropnews/2017/07/influence-drought-corn-and-soybean


Context: The registration process also calls for an estimate of consumptive water use. Consumptive water use is the amount of water that is lost from the area of withdrawal. Since most water pumped for crop irrigation ultimately goes into evapotransporation, the consumptive use is estimated to be high or about 90%. Water used for harvest cooling is mostly retuned back to surface or groundwater so the consumptive use is estimated to be low or about 5 to 10%.

Question: What causes the consumptive use to be low?

Answer: harvest cooling is mostly retuned back to surface or groundwater

Kelley, L. (2007). Irrigation Fact Sheet #4 - Michigan Registration for New Agricultural Withdrawals. https://www.canr.msu.edu/uploads/235/67987/lyndon/MIRegNewAgWith.pdf


Context: (1) Enviroweather: computes daily estimate of potential E.T. and projects E.T. demands for 7 days at each of the 58 strategically located weather stations in Michigan calculating crop E.T. using wind, relative humidity, and net solar radiation in addition to temperature to estimate crop E.T. demands. Pick the station nearest to you, and then click on one of the categories listed near the top of the screen (eg. Field crops, Fruit), then click on Potential Evapotranspiration. For corn and soybeans clicking the Crop ET Estimate button then entering the emergences date allowing tracking crop ET as the crop develops. A free service of Enviroweather Network sends daily reports of ET from the previous 4 days and projected values for the next week by text or E-mail to producers that signed up.

Question: At which location can you use Enviroweather?

Answer: 58 strategically located weather stations in Michigan

Kelley, L., & Miller, S. (2019). Irrigation Fact Sheet #3 - Irrigation Scheduling Tools. https://www.canr.msu.edu/uploads/236/43605/FactSheets/3_IrrigationSchedulingTools5.14.pdf


Context: Sub-leasing: One major issue that needs to be considered in the negotiations of adding irrigation is the ability for the lessee to sublet the property. As high dollar specialty crop become more common in the area opportunity to rent irrigated land for a single production year for nearly double the local irrigated rent rate become a reality. Annual sub-renting could leave land owners with an unfamiliar face to deal with if neighbor water well issue arises. Addressing sub-leasing issue in writing can avoid grief and confusion in the future.

Question: Why is the opportunity to sublet irrigated land for nearly double the local irrigated rent rate becoming a reality?

Answer: As high dollar specialty crop become more common

Kelley, L. (2009a). Irrigation Fact Sheet #6 - Irrigation Aspects of Land Lease Agreements. https://www.canr.msu.edu/uploads/235/67987/lyndon/LandRent.pdf


Context: (8) Check center pivot sprinkler patterns: With water up to pressure, check sprinkler patterns. This can be easily done on bare earth or when crops are small. Look for sprinklers that have smaller wetted patterns than others. Plugs, no-turns, and watering patterns would indicate damage or obstruction. Check pressure at the pivot point and the last sprinkler and compare to the sprinkler chart, pressure thatdiffers from the chart by more than 10% indicates the need for attention.

Question: What is a prerequisite for checking sprinkler patterns?

Answer: With water up to pressure

Kelley, L. (2017). Irrigation Fact Sheet #15 - Irrigation Inspection and Repair. https://www.canr.msu.edu/uploads/235/67987/factsheets/15_Irriation_Inspection_and_Repair_v2_4.21.17.pdf


Context: A simple, inexpensive catch can stand can be built using: 1. 32 oz. disposable soda cup (Taco Bell cup) 2. 3 inch plastic drain pipe cut to 5 inch in length 3. 2 x 3 inch stud, cut to length to wedge into plastic drain pipe (drill hole partially through the chunk of wood to accommodate the fence post) 4. Steel (step-in) electric fence post

Question: What should be the size of a cup used to build a catch can stand?

Answer: 32 oz

Kelley, L. (2020). Irrigation Fact Sheet #16 - Catch Can Stands for Rain Gauges and Uniformity Check for Evaluating Irrigation.


Context: (1) Check and test all control and power boxes: With all power off, open each electric box and blow it out with compressed air. Avoid leaving any dust or debris in the box or connections. Seal holes that rodents, snakes or insects may use to gain access to the box. A small application of an insecticide with a long residual time to the bottom of the box can reduce ant and spider problems in the future. Make sure disconnects function and repair or replace faulty equipment. Also make sure all connections are tight and all connection surfaces are free of corrosion. Many electrical disconnects or pivot control boxes meet an early demise from electrified mouse nest explosion in the box.

Question: How can I reduce ant and spider problems in the future when it comes to my control and power boxes?

Answer: A small application of an insecticide with a long residual time to the bottom of the box

Kelley, L. (2017). Irrigation Fact Sheet #15 - Irrigation Inspection and Repair. https://www.canr.msu.edu/uploads/235/67987/factsheets/15_Irriation_Inspection_and_Repair_v2_4.21.17.pdf


Context: New wells and surface water withdrawals in Michigan, installed after February, 2006, that are capable of pumping 100000 gallon per day (70 gpm) are now required to register with Michigan Department of Agriculture prior to beginning to pump. All water withdrawals that reported prior to 2006 are considered properly registered. Forms are available directly from the MDA website or from the St. Joseph County MSU Extension website then navigate to link for irrigation on the left hand side.

Question: Who are new wells and surface water withdrawals in Michigan installed after February 2006 required to be registered with?

Answer: Michigan Department of Agriculture

Kelley, L. (2007). Irrigation Fact Sheet #4 - Michigan Registration for New Agricultural Withdrawals. https://www.canr.msu.edu/uploads/235/67987/lyndon/MIRegNewAgWith.pdf


Context: The inherent risk of injecting fertilizer into a water system dictates the need for backflow protection. Both Indiana and Michigan have resource protection rules that require the use of Chemigation valves for the protection of both surface and ground water sources. Chemigation valves create an air gap in the pipe line downstream from the pump when the pump is shut down. The air gap breaks the suction created by water retreat back to groundwater or surface water. Chemigation valves for most irrigation application are available from local irrigation dealers for less than $700. Installation cost is much less at the time of pump installation and should be included in almost all new irrigation pumping installations.

Question: Where do chemigation valves create an airgap in the pipeline?

Answer: downstream from the pump

Kelley, L. (2013). Irrigation Fact Sheet #12 - Nitrogen Application with Irrigation. https://www.canr.msu.edu/uploads/235/67987/FactSheets/12_NitrogenApplicationWithIrrigationFact_Sheet.pdf


Context: (9) Check solid set system coverage patterns: Coverage from a solid set system is dependent on each individual sprinkler. Inspect the coverage after bringing the system to designed pressure. Visual inspection of each sprinkler while running will often find the major problems. Comparing pressure reading from sprinklers furthest from the source to the design specification will often indicate hidden leaks or under supplied systems.

Question: What do you gain from comparing pressure reading from sprinklers furthest from the source to the design specification?

Answer: will often indicate hidden leaks

Kelley, L. (2017). Irrigation Fact Sheet #15 - Irrigation Inspection and Repair. https://www.canr.msu.edu/uploads/235/67987/factsheets/15_Irriation_Inspection_and_Repair_v2_4.21.17.pdf


Context: Even when the lessee provides all off the irrigation equipment and the water supply, rent value should be expected to be higher than local dry land rent prices. Land rent prices for irrigated ground are often higher than the cost of installing irrigation spread over a seven or ten year schedule. In most situations the additional profit for establishing irrigation on rental property is evident or the lessee would not be seeking to proceed. This opportunity cost for irrigation may be as small as 10% of the rent value or as great as 200% added to local dry land rent values. The prevalence of high dollar irrigated specialty crops are a major factor in the variability.

Question: Are land rent prices higher or lower than the cost of installing irrigation?

Answer: higher

Kelley, L. (2009a). Irrigation Fact Sheet #6 - Irrigation Aspects of Land Lease Agreements. https://www.canr.msu.edu/uploads/235/67987/lyndon/LandRent.pdf


Context: (1a) Existing on February 28, 2006 ' Subject to water use reporting. These withdrawals from either wells or surface water are exempt from the new adverse resource impact standards. This is often termed as "Grandfathering", but these withdrawals may still be required to share the water resource with both other "grandfathered" users and with all new users since the legislation still hold Michigan's water use as a riparian right.

Question: Why should "grandfathered" withdrawals still share water sources?

Answer: since the legislation still hold Michigan's water use as a riparian right.

Kelley, L., Miller, S., & Loudon, T. (2006). Irrigation Fact Sheet #1- Agricultural Water Use Reporting for 2006 Changes in Water Use Regulation. https://www.canr.msu.edu/uploads/235/67987/FactSheets/1_AgWaterUseReporting11-29-06.pdf


Context: Crop water use estimates can assist producers in irrigation decision making. A good source of E.T. rate charts for the most commonly irrigated crops is Irrigation Scheduling Checkbook Method from the University of Minnesota. Additional irrigation scheduling information can be found at the MSU irrigation website.

Question: Why should I know crop water use?

Answer: can assist producers in irrigation decision making

Kelley, L. (2014c). Irrigation Fact Sheet #14  - Irrigation Application Volumes. https://www.canr.msu.edu/uploads/235/67987/FactSheets/14_IrrigationApplication.pdf


Context: Applying nitrogen fertilizer or crop protection products through a center pivot is an efficient and effective method. In fact, it is a well-documented best management practice to apply nitrogen fertilizer as close to the time the corn will use it to get the most efficient use of the fertilizer. Most of the products are injected into the pivot with a fixed rate injection pump. So, how does one figure the pumping rate to set the pump at, and what about the change the end gun causes when it's turned on and off? We will discuss both challenges in this article.

Question: What is an efficient and effective method of applying nitrogen fertilizer or crop protection products?

Answer: through a center pivot

Melvin, S. (2023a). How to Determine the Chemigation Injection Pump Setting for a Center Pivot with the End Gun Off and On. UNL CropWatch. https://cropwatch.unl.edu/2023/how-determine-chemigation-injection-pump-setting-center-pivot-end-gun-and


Context: Effects on corn during grain fill: During grain fill drought stress results in premature death of leaf tissue, shortened grain fill periods, increased lodging, fewer kernels, and light kernel weights. Kernel abortion near the ear tip will occur in the two weeks following pollination. Continued drought into the milk stage will result in further kernel abortion and smaller, lighter kernels. Drought that occurs in the mid to late grain filling period (milk, dough, and dent stages) results in decreased kernel weights and premature physiological maturity. Once physiological maturity occurs additional drought stress will have no impact on grain yield. Because drought stress typically coincides with higher than normal temperatures the grain fill period is often reduced.

Question: What can cause further kernel abortion?

Answer: Continued drought into the milk stage

Licht, M., & Archontoulis, S. (2017). Influence of Drought on Corn and Soybean | Integrated Crop Management. https://crops.extension.iastate.edu/cropnews/2017/07/influence-drought-corn-and-soybean


Context: Drought symptoms in corn: Corn leaf rolling is the primary symptom of drought. Greying of leaf tissue will occur under extremely severe conditions. The earlier leaf rolling occurs in the day or the longer the duration of leaf rolling the greater the stress the crop is under. Yield loss estimates are assumed when drought stress occurs for four consecutive days or more.

Question: When does greying of corn leaf tissue occur?

Answer: will occur under extremely severe conditions

Licht, M., & Archontoulis, S. (2017). Influence of Drought on Corn and Soybean | Integrated Crop Management. https://crops.extension.iastate.edu/cropnews/2017/07/influence-drought-corn-and-soybean


Context: Effects on vegetative soybean: Vegetative growth of soybean during drought is diminished. Drought stressed soybean are often shorter with smaller leaves due to a lack of water, nutrient availability, and nutrient uptake. Soybean root growth increases during drought conditions because plant carbohydrates are shifted to root growth. When adequate rainfall or soil moisture returns, vegetative growth will resume until the mid-seeding filling stage (R5.5). Under severe drought stress, soybean flowering may occur earlier than normal in an effort to produce seed before premature death.

Question: What happens to soybean roots during drought conditions?

Answer: Soybean root growth increases

Licht, M., & Archontoulis, S. (2017). Influence of Drought on Corn and Soybean | Integrated Crop Management. https://crops.extension.iastate.edu/cropnews/2017/07/influence-drought-corn-and-soybean


Context: Iowa soils hold 1.5-2.5 inches per foot of effective rooting depth. Root depth in Iowa has been found at depths greater than six feet. The importance of proper early root development cannot be underestimated. Crops with deep root systems explore a greater volume of soil are able to withstand drought conditions better.

Question: At what kind of depths has root depth in Iowa been found?

Answer: at depths greater than six feet

Licht, M., & Archontoulis, S. (2017). Influence of Drought on Corn and Soybean | Integrated Crop Management. https://crops.extension.iastate.edu/cropnews/2017/07/influence-drought-corn-and-soybean


Context: Table 1. Example corn yield loss estimates when stress occurs for four or more consecutive days. Adapted from Classen and Shaw, 1970; Rhoads and Bennet, 1990; and Shaw, 1988.  The Corn Development stage known as early vegetative (VE - V12) has an estimated Yield Loss per Day of Stress of 1-3. The Corn Development stage known as Late vegetative (V12 to VT) has an Estimated Yield Loss per Day of Stress of 2-5. The Corn Development stage known as Pollination to Blister (R2) has an Estimated Yield Loss per Day of Stress of 3-9. The Corn Development stage known as Milk (R3) has an Estimated Yield Loss per Day of Stress of 3-6. The Corn Development stage known as Dough (R4) has an Estimated Yield Loss per Day of Stress of 3-5. The Corn Development stage known as Dent (R5) has an Estimated Yield Loss per Day of Stress of 2-4. The Corn Development stage known as Maturity (R6) has an Estimated Yield Loss per Day of Stress of 0.

Question: What is the short hand for the maturity development stage of corn?

Answer: R6

Licht, M., & Archontoulis, S. (2017). Influence of Drought on Corn and Soybean | Integrated Crop Management. https://crops.extension.iastate.edu/cropnews/2017/07/influence-drought-corn-and-soybean


Context: Michigan's 2006 water use legislation limited large volume water use to prevent an adverse resource impacted would be expected. 2008 water use legislation added a limit of no greater than 25% of a watersheds index flow (defined as the median average August flow) could be used by large volume water users. Developments of a screening tool to estimate each watershed low summer stream flow and the potential impact by large volume water use was started in late 2006 with release late 2008. The screening tool estimates how much water can be used in each watershed in Michigan without causing a detrimental effect to characteristic fish populations in the watershed. Michigan's Water Withdrawal Assessment Tool is available for use online.

Question: Why did Michigan limit large volume water use?

Answer: to prevent an adverse resource

Kelley, L. (2009c). Irrigation Fact Sheet #9 - Michigan Large Volume Water Use Requirements. https://www.canr.msu.edu/uploads/235/67987/lyndon/9largewaterwith.pdf


Context: Early in the season our irrigation goals are often focused on germinating seed and incorporating fertilizers or pre-emergent herbicides. In a normal year, May and early June often receive adequate rainfall to meet the needs of the developing crops and plant roots will grow into moisture that is stored deeper in the soil profile. Chances of receiving additional rainfall in the near future are rather good, so irrigation applications are kept to a minimum with the hope that nature will be providing more water soon. Roots that are not fully established leave only a limited soil water holding capacity capable making small application ideal.

Question: What kind of roots leave a limited soil water holding capacity capable that make small application ideal?

Answer: Roots that are not fully established

Kelley, L. (2014b). Irrigation Fact Sheet #14  - Irrigation Application Volumes. https://www.canr.msu.edu/uploads/235/67987/FactSheets/14_IrrigationApplication.pdf


Context: Estimating Annual Irrigation Costs. Annual irrigation cost can be divided into two categories: annual cost of ownership and the annual cost of operation - mainly the cost of energy and labor. The annual cost of ownership is often estimated by the DIRTI (Depreciation, Interest, Repairs, Taxes, and Insurance) formula which spreads the actual cost of ownership of an equipment investment over its usable lifespan or investment period. A standard procedure is outlined on page 7 of MSU Extension Bulletin E-2131, "Custom Work Rates in Michigan". This formula can provide you with the annual cost of the original investment in equipment and improvements.

Question: What does the R stand for in DIRTI?

Answer: Repairs

Kelley, L. (2007b). Irrigation Fact Sheet #5 - Estimating Annual Irrigation Costs. https://www.canr.msu.edu/uploads/235/67987/irrigation_costs/5_Estimating_Annual_Irrigation_Costs.pdf


Context: Question: What is the disadvantage of using a drip system? Excerpt: No serious introduction to drip irrigation would be complete without a look at the disadvantages associated with its use:Drip irrigation should have a pressure regulator and filter to protect the drip system.The soft poly tubing can be susceptible to damage from insects, rodents, and household pets.A filter is required to guard against potential clogging at the very small orifices of the drippers and micro sprinklers.You cannot see a drip system working as you can a conventional sprinkler system.Drip irrigation creates a smaller wetted area, so control is more critical to avoid stress for the plants.

Question: What is needed to protect the drip system?

Answer: a pressure regulator and filter

DIG Corp. (2024). Drip Irrigation FAQ’s. https://www.digcorp.com/drip-irrigation-faqs/


Context: Corn management and yield loss: Management depends on the remaining yield potential. Each field provides a unique combination of soil, management, hybrid, and water supply so not all the fields will have the same yield reduction. After pollination a key is to determine how successful pollination was; that is how many kernels per ear were attained. This can be determined by performing a shake test to see if silks are still attached to the ovules (unfertilized kernels); silks will easily drop from fertilized ovules (kernels). Or wait until seven to ten days after pollination when the ear is in the blister stage (plump kernels with watery liquid inside) to see how many kernels are expanding.

Question: When should I see how many kernels are expanding?

Answer: when the ear is in the blister stage

Licht, M., & Archontoulis, S. (2017). Influence of Drought on Corn and Soybean | Integrated Crop Management. https://crops.extension.iastate.edu/cropnews/2017/07/influence-drought-corn-and-soybean


Context: Instructions for completing the Evaluating Potential Irrigation Runoff Form. (5) Record observations at each observation point. Observation should be made when the observation points is in the second half of the wetted area as the system moves away from the site. Look at several (four to five) areas representing the row contour and differences in row traffic of the location. Record any specific concerns that may affect the application (drips or leaks) or affect the soil's ability to take in water (compaction, row contours, etc.).

Question: How many areas representing the row contour and differences in row traffic should I look at?

Answer: four to five

Kelley, L. (2014b). Irrigation Fact Sheet #13 - Reducing and Evaluating Irrigation Runoff. https://www.canr.msu.edu/uploads/236/43605/FactSheets/13_ReducingAndEvaluatingIrrigationRunoff_5-9-14.pdf


Question: After how many days are yield loss estimates assumed when drought stress occurs?

Answer: for four consecutive days or more

Licht, M., & Archontoulis, S. (2017). Influence of Drought on Corn and Soybean | Integrated Crop Management. https://crops.extension.iastate.edu/cropnews/2017/07/influence-drought-corn-and-soybean


Context: A raise in rent values greater than just recovering the investment in the water well is justified since the well allows a greater net profit with lower risk then dry land farming. The additional profit above the cost of the addition of irrigation is often split between landlord and lessee.

Question: What is the benefit of a well compared to dry land farming?

Answer: additional profit above the cost of the addition of irrigation

Kelley, L. (2007b). Irrigation Fact Sheet #5 - Estimating Annual Irrigation Costs. https://www.canr.msu.edu/uploads/235/67987/irrigation_costs/5_Estimating_Annual_Irrigation_Costs.pdf


Context: Instructions for completing the Evaluating Potential Irrigation Runoff Form. (3) Set the machine for an irrigation amount typically used (timer setting, system speed, run time) and run the machine across the identified area. Record the system settings.

Question: What is the third step in completing the Evaluating Potential Irrigation Runoff Form?

Answer: Set the machine for an irrigation amount typically used (timer setting, system speed, run time) and run the machine across the identified area. Record the system settings.

Kelley, L. (2014a). Irrigation Fact Sheet #7- Reducing and Evaluating Irrigation Runoff.Instantaneous irrigation application rates compared to soil infiltration rates. https://www.canr.msu.edu/uploads/235/67987/FactSheets/7_ReducingAndEvalRunoff.pdf


Context: The irrigation application rate will vary throughout the length of a center pivot irrigation system, with the highest instantaneous application rate at the end of the system furthest from the pivot point. Irrigation application rate will be uniform for solid set and large gun hose traveler irrigation systems as long as application time or forward travel of system is unchanged.

Question: What does the application rate look like throughout the length of a center pivot irrigation system?

Answer: will vary throughout the length of a center pivot irrigation system

Kelley, L. (2014b). Irrigation Fact Sheet #13 - Reducing and Evaluating Irrigation Runoff. https://www.canr.msu.edu/uploads/236/43605/FactSheets/13_ReducingAndEvaluatingIrrigationRunoff_5-9-14.pdf


Context: (6) Rock traps, screens and filters - Remove debris, sand and small stones from rock traps. Clean screens and filters often used in conjunction with end guns and cornering arms. Rock traps are often removed for the winter to prevent freeze damage from water condensation in pipe and accumulating in trap. If rock traps were removed for the winter and bird guards are not put in place inspect openings for nests.

Question: What is often used in conjunction with end guns and cornering arms?

Answer: Clean screens and filters

Kelley, L. (2017). Irrigation Fact Sheet #15 - Irrigation Inspection and Repair. https://www.canr.msu.edu/uploads/235/67987/factsheets/15_Irriation_Inspection_and_Repair_v2_4.21.17.pdf


Context: Question: What is the advantage and benefits of using drip irrigation system? Excerpt: The advantage and benefits are more than just saving water.Water Efficiency: By applying water only where and when it is needed, with less runoff, deep percolation, and evaporation from leaves and soil, the uniform application of water from drip irrigation systems can achieve high water savings ranging upwards to 60%.Ease of Installation: A drip system can be installed without special tools or glue, and with limited knowledge, therefore making the installation a very simple process. DIG's low volume irrigation systems install easily above or below the ground.Reduced Pest Problems and Weed Growth: Watering only the roots of the plants using drip irrigation cuts down on water-borne pests and fungal diseases that spread by water movement, as well as the germination of weeds in the areas between plants.Versatility: Low volume irrigation systems are designed for placement in both new and existing landscape areas, and are ideal for installation on difficult terrain such as on slopes, in oddly shaped areas, and on windy sites.Root Zone: One of the most important aspects of drip irrigation is the fact that in many instances, a totally new and more favorable root zone environment is created and a relatively constant soil moisture level is maintained. This fact has important implications on plants because it bears upon questions of plant water requirements, tolerance and control of disease.Economy: Investing in a low volume irrigation system can save you money and significantly lower your water use.Long Life: All DIG products are designed to withstand the harshest conditions in both home and commercial installations. They are manufactured of high quality, highly durable plastics and contain added quantities of the compound Carbon Black, making them resistant to the damaging effects of ultraviolet rays.

Question: How much water can you save by using drip irrigation?

Answer: upwards to 60%

DIG Corp. (2024). Drip Irrigation FAQ’s. https://www.digcorp.com/drip-irrigation-faqs/


Context: The registration process also calls for an estimate of consumptive water use. Consumptive water use is the amount of water that is lost from the area of withdrawal. Since most water pumped for crop irrigation ultimately goes into evapotransporation, the consumptive use is estimated to be high or about 90%. Water used for harvest cooling is mostly retuned back to surface or groundwater so the consumptive use is estimated to be low or about 5 to 10%.

Question: What is consumptive water use?

Answer: the amount of water that is lost from the area of withdrawal.

Kelley, L. (2007). Irrigation Fact Sheet #4 - Michigan Registration for New Agricultural Withdrawals. https://www.canr.msu.edu/uploads/235/67987/lyndon/MIRegNewAgWith.pdf


Question: Does soybean root growth increase or decrease during drought conditions?

Answer: increases

Licht, M., & Archontoulis, S. (2017). Influence of Drought on Corn and Soybean | Integrated Crop Management. https://crops.extension.iastate.edu/cropnews/2017/07/influence-drought-corn-and-soybean


Context: In the summer of 2012, daily crop water use (E.T.) for many crops exceeded 0.30 inches per day for several days in early July. Maintaining an adequate reserve of soil moisture is a good insurance policy to help plants manage stress during periods of high temperature. To build in a reserve for extended periods of drought, downtime for repairs, or periods of extreme temperatures and wind, irrigation goals during the peak water use period should be to maintain moisture levels high with enough room to capture a one inch rainfall.

Question: What was the daily crop water use of many crops in the summer of 2012?

Answer: exceeded 0.30 inches per day for several days in early July

Kelley, L. (2013a). Efficient irrigation application volumes change throughout crop development. https://www.canr.msu.edu/news/efficient_irrigation_application_volumes_change_throughout_crop_development


Context: Evapotransporation rate (E.T.) is a term that represents the daily water lost by the plants maintenance and growth along with the evaporative loss from the soil surface. E.T. rates for almost all crops grown in northern Indiana and Michigan have rates under 0.25 inches per day for all but a few extreme days.

Question: When is the E.T. rate for most crops in northern Indiana and Michigan not 0.25 inches per day?

Answer: extreme days

Kelley, L. (2007b). Irrigation Fact Sheet #5 - Estimating Annual Irrigation Costs. https://www.canr.msu.edu/uploads/235/67987/irrigation_costs/5_Estimating_Annual_Irrigation_Costs.pdf


Context: How to Get More Out of Your Irrigation System: (7) Reduce nitrogen fertilizer loss to volatilization. Water in nitrogen application with  0.5 inch or more of irrigation water to move nitrogen into the soil.

Question: How much water should I use in nitrogen application in order to move nitrogen into the soil?

Answer: 0.5 inch or more of irrigation water

Kelley, L. (2009b). Irrigation Fact Sheet #8 - How to Get More from your Irrigation System. https://www.canr.msu.edu/uploads/235/67987/lyndon/HGMIrrSys.pdf


Context: Question: What are the important parameters I should look at in an irrigation water quality report? Excerpt: Most irrigation water analysis reports will provide a list of cations (calcium, magnesium, sodium and potassium) and anions (bicarbonate, carbonate, sulfate and chloride) along with pH, total dissolved solids (TDS), electrical conductivity (EC) and the sodium adsorption ratio (SAR). The cations, anions and TDS will be listed as milligrams per liter (mg/l) or the equivalent, parts per million (ppm). The two most important factors are TDS or EC and SAR. The TDS of a water sample is a measure of the concentration of soluble salts in the water, which include all the cations and anions. TDS is estimated from the EC of the water. The more dissolved minerals in the water, the higher the EC. The units of EC can be listed as millimhos per centimeter (mmhos/cm), micromhos per centimeter (umhos/cm) or deciSiemens per meter (dS/m). One millimho per centimeter is equal to 1000 micromhos per centimeter or 1 dS/m. TDS can be estimated by multiplying the EC (in umhos/cm) by 0.64. For example, the TDS of a water sample with an EC of 2000 umhos/cm (2.0 dS/m) would be about 1280 mg/l. The SAR of a water sample is the proportion of sodium to calcium and magnesium in the water. Since it is a ratio, SAR has no units. For most soils in North Dakota, any water with an EC greater than 2000 micromhos per centimeter (2 mmhos/cm or 2 dS/m) or an SAR value greater than 6 is not generally recommended for continuous irrigation. However, soils with a high sand content can use water with an SAR up to 9.

Question: What are the units associated with SAR?

Answer: SAR has no units

Fipps, G. (2021). Irrigation Water Quality Standards And Salinity Management Strategies. https://irrigation.tamu.edu/files/2021/04/EB-1667.pdf


Context: Question: What do I do if the water leak is between the water meter and backflow assembly? Excerpt: In this situation, the only solution is to turn the water off at the irrigation meter.

Question: What do I do if the water leak is between the water meter and backflow assembly?

Answer: turn the water off at the irrigation meter.

Carolina Irrigation. (2024). FAQ | Carolina Irrigation | Residential & Commercial Irrigation Experts Since 1999. https://www.carolinairrigation.net/faq


Context: Question: I want to run my system three times per week.' How long should each zone run? Excerpt: Individual circumstances will vary, but as a general rule, depending on the season, spray heads should run between 5 - 15 minutes, rotors should run 15 - 30 minutes, and drip lines should run 30 minutes to 1 hour.

Question: I want to run my system three times per week. How long should rotors run?

Answer: 15 - 30 minutes

Carolina Irrigation. (2024). FAQ | Carolina Irrigation | Residential & Commercial Irrigation Experts Since 1999. https://www.carolinairrigation.net/faq


Context: Effects on corn during grain fill: During grain fill drought stress results in premature death of leaf tissue, shortened grain fill periods, increased lodging, fewer kernels, and light kernel weights. Kernel abortion near the ear tip will occur in the two weeks following pollination. Continued drought into the milk stage will result in further kernel abortion and smaller, lighter kernels. Drought that occurs in the mid to late grain filling period (milk, dough, and dent stages) results in decreased kernel weights and premature physiological maturity. Once physiological maturity occurs additional drought stress will have no impact on grain yield. Because drought stress typically coincides with higher than normal temperatures the grain fill period is often reduced.

Question: What are the consequences of drought stress on corn during grain fill?

Answer: premature death of leaf tissue, shortened grain fill periods, increased lodging, fewer kernels, and light kernel weights

Licht, M., & Archontoulis, S. (2017). Influence of Drought on Corn and Soybean | Integrated Crop Management. https://crops.extension.iastate.edu/cropnews/2017/07/influence-drought-corn-and-soybean


Context: Irrigated production has the advantage of fertigation as an option in nitrogen management. Fertigation is the process of applying fertilizer through irrigation water. Liquid 28% nitrogen is the most common product for fertigation, but urea and micro-nutrient solutions are also available to meet crop nutrient needs, with proper equipment.

Question: What is fertigation?

Answer: the process of applying fertilizer through irrigation water.

Kelley, L. (2013). Irrigation Fact Sheet #12 - Nitrogen Application with Irrigation. https://www.canr.msu.edu/uploads/235/67987/FactSheets/12_NitrogenApplicationWithIrrigationFact_Sheet.pdf


Context: Maximum economic yield with minimum amount of irrigation is a goal for most irrigators. Efficient irrigation water use means providing enough water to avoid drought stress, but not so much that water is lost out of the rooting zone or to runoff from the surface. This includes leaving enough water holding capacity to capture the next normal rainfall thus not losing the value of rainfall and also reduce the risk of leaching and run-off. In the irrigated region of northern Indiana and Michigan evaporate losses during irrigation application are minimal due to high humidity. The humid condition cause several differences in irrigation management for efficiency compared to the arid west.

Question: What should I consider when I water my crops?

Answer: leaving enough water holding capacity

Kelley, L. (2014c). Irrigation Fact Sheet #14  - Irrigation Application Volumes. https://www.canr.msu.edu/uploads/235/67987/FactSheets/14_IrrigationApplication.pdf


Context: Question: How do I know if my rain sensor is working? Excerpt: Make sure sensor switch on controller is in active position.' Start a manual cycle on your system, push down on center tab on top of sensor.' If system shuts off, the sensor is working.

Question: How do I know if my rain sensor is working?

Answer: Make sure sensor switch on controller is in active position.' Start a manual cycle on your system, push down on center tab on top of sensor.' If system shuts off, the sensor is working.

Carolina Irrigation. (2024). FAQ | Carolina Irrigation | Residential & Commercial Irrigation Experts Since 1999. https://www.carolinairrigation.net/faq


Context: Increasing the amount of water that may enter the soil in a given period of time: The instantaneous irrigation application rate will vary throughout the length of a center pivot irrigation system, with the highest instantaneous application rates at the end of the system furthest from the pivot point. Instantaneous irrigation application rate will be uniform for solid set and large gun hose traveler irrigation systems as long as application time or forward travel of system is unchanged.

Question: What kinds of irrigation systems can guarantee uniform instantaneous application rates?

Answer: solid set and large gun hose traveler irrigation systems

Kelley, L. (2014a). Irrigation Fact Sheet #7- Reducing and Evaluating Irrigation Runoff.Instantaneous irrigation application rates compared to soil infiltration rates. https://www.canr.msu.edu/uploads/235/67987/FactSheets/7_ReducingAndEvalRunoff.pdf


Context: Infiltration rate decreases with increased wetting time. Therefore, the amount of water applied during each application affects the fraction of water that enters the soil and the fraction of runoff. Small pockets and depressions in the soil surface hold a volume of water at that location until the soil surface receives the water. Midseason cultivation or in-row soil surface modification (i.e. dammer/diker) increases the surface storage.

Question: What holds a volume of water until the soil surface receives the water?

Answer: Small pockets

Kelley, L. (2014a). Irrigation Fact Sheet #7- Reducing and Evaluating Irrigation Runoff.Instantaneous irrigation application rates compared to soil infiltration rates. https://www.canr.msu.edu/uploads/235/67987/FactSheets/7_ReducingAndEvalRunoff.pdf


Context: The Water Withdrawal Assessment Tool (WWAT) is designed to estimate the likely impact of a water withdrawal on nearby streams and rivers. Use of the WWAT is required of anyone proposing to make a new or increased large quantity withdrawal from the waters of the state, including all groundwater and surface water sources, prior to beginning the withdrawal. You must use the WWAT to determine if a proposed withdrawal is likely to cause an Adverse Resource Impact, and to register the withdrawal. The results page provides a quick link to submitting a registration. A registration is valid for 18 months; the withdrawal capacity must be installed within that 18 months or the registration becomes void.

Question: Where can I register a water withdrawal site?

Answer: The Water Withdrawal Assessment Tool (WWAT)

EGLE. (2023). WWAT-Home Page. https://www.egle.state.mi.us/wwat/(S(whxx1bja4grx05ino0gubkx4))/default.aspx


Context: Estimating Annual Irrigation Costs. Annual irrigation cost can be divided into two categories: annual cost of ownership and the annual cost of operation - mainly the cost of energy and labor. The annual cost of ownership is often estimated by the DIRTI (Depreciation, Interest, Repairs, Taxes, and Insurance) formula which spreads the actual cost of ownership of an equipment investment over its usable lifespan or investment period. A standard procedure is outlined on page 7 of MSU Extension Bulletin E-2131, "Custom Work Rates in Michigan". This formula can provide you with the annual cost of the original investment in equipment and improvements.

Question: On which page of MSU Extension Bulletin E-2131 can you find the standard procedure pertaining to the DIRTI formula?

Answer: page 7

Kelley, L. (2007b). Irrigation Fact Sheet #5 - Estimating Annual Irrigation Costs. https://www.canr.msu.edu/uploads/235/67987/irrigation_costs/5_Estimating_Annual_Irrigation_Costs.pdf


Question: How high should irrigation goals during the peak water use period be to maintain moisture levels?

Answer: with enough room to capture a one inch rainfall

Kelley, L. (2013a). Efficient irrigation application volumes change throughout crop development. https://www.canr.msu.edu/news/efficient_irrigation_application_volumes_change_throughout_crop_development


Context: (5) Water registration. Irrigation water use almost always is considered a large volume water use (capacity to pump > 70 gal./min). In both Indiana and Michigan new installations require a registration. In Indiana this is handled by Indiana DNR. In Michigan you will need to work through the Michigan Water Withdrawal Assessment Tool to determine if your proposed water use is likely to cause a negative environmental impact. At the end of the process you will either be able to register online or may be required to request a site specific review by MDEQ. MDEQ site specific reviews may result in allocation of the water resulting in registration or the opportunity to bring together all large volume water users in the watershed to negotiate reducing use by existing water users to allow allocations for a new water use.

Question: What must be done to register my irrigation in Michigan?

Answer: the Michigan Water Withdrawal Assessment Tool to determine if your proposed water use is likely to cause a negative environmental impact

Kelley, L. (2022). Irrigation Fact Sheet #11- Checklist for Planning Irrigation Systems. https://www.canr.msu.edu/irrigation/upoads/files/11ChecklistForPlanningIrrigationSystems08