After years of drought, the 2019 winter is turning out to be a good one for California’s water supply. Several winter storm systems in the past couple of months means there is plenty of water. In some parts of the state, more than plenty, as evidenced from flooding events. Snow pack is above average (156%) and reservoirs are sufficiently full. So, farmers can rest easy, eh? Not so fast.
Some of you may have heard that in December 2018 the State Water Resource Board announced that up to 50% of the water flowing through Lower San Joaquin River and its tributaries – the Stanislaus, Merced and Tuolumne river will be required to flow unimpaired, i.e. without diversions. The Water Board contends this is needed to restore critically endangered fish species dependent on the flow. A second phase of the plan would see similar flow requirements for the Sacramento River and its tributaries – the Feather, Yuba and American Rivers. As you can imagine, this will have a severe impact on agriculture dependent on this water.
However, this is not a done deal. There are other regulatory processes that must be followed before the plan can go into effect. But already, legal challenges have been made to this so called “Bay Delta Plan”. Several agricultural commodity groups, including the California Walnut Commission, have voiced their opposition. Critics of the plan argue that voluntary water sharing agreements between various stakeholders can yield better results than arbitrary unimpaired flow decisions. Furthermore, they point out that water flow is just one of the factors affecting species survival. Habitat loss is another critical factor to be taken into account. Mere unimpaired water flow would not be as beneficial to species restoration. To that end, cooperation among various stakeholder groups-agricultural water rights, urban drinking water, and environmental groups, is the appropriate way to go.
Another regulatory issue of importance is the Sustainable Groundwater Management Act (SGMA). This was passed in 2014, at the height of the California drought, to avoid severe depletion of groundwater and its quality. The first phase of SGMA implementation is approaching in 2020. Local water agencies will need to start implementing Groundwater Sustainability Plans (GSP), which will include annual tabulation of how much groundwater is being extracted. Growers should have heard by now from their local water agencies as to which Groundwater Sustainability Agencies (GSA) they belong to and what the annual reporting requirements are.
Regardless of the regulatory issue, the California Walnut Commission will continue to make sure the opinions of the California Walnut industry are represented.
Rep. Mike Thompson (D-Napa Valley, CA), the founder and Co-Chair of the Congressional Wine Caucus, announced today that Rep. Dan Newhouse (R-Yakima Valley, WA) has been selected as the new Co-Chair of the Wine Caucus. Newhouse, a lifelong farmer and winegrape grower, represents the premier wine regions of Columbia Valley, Yakima Valley and the Walla Walla Valley. Newhouse will serve as only the fifth Co-Chair of the Wine Caucus in its 20-year history and the first Co-Chair from outside of California.
“Over the years, Mike has built the Wine Caucus into a bipartisan institution on Capitol Hill and an invaluable resource for the 10,000 wineries all across the country,” said Robert P. “Bobby” Koch, President & CEO of Wine Institute. “We are thrilled with the selection of Rep. Newhouse as the new caucus Co-Chair and know that he and Mike will continue to do everything they can to support and grow value-added agriculture like wine. Rep. Newhouse’s vast experience in agriculture in the Pacific Northwest will only strengthen the caucus as it pursues key industry priorities including renewal of the Craft Beverage Modernization Act and opening up critical export markets.”
“When the Congressional Wine Caucus was founded, we had a mission to educate our fellow Members about the strong economic contributions made by grapegrowers and winemakers to our communities and to ensure they have a voice in Congress. I am proud that my new Co-Chair, Rep. Dan Newhouse, is a fellow grapegrower and knows these issues firsthand,” said Thompson. “Together we will continue our mission of advocacy and education in order to support our nation’s incredible wine community from the vineyard to the glass.”
“I am proud to represent the flourishing, high-quality wine region of Central Washington, and I am honored to join my friend and colleague Rep. Mike Thompson to serve as the first Co-Chair of the Congressional Wine Caucus from Washington State,” said Rep. Newhouse. “Mike truly understands the priorities and concerns of the wine community, and I look forward to working with him to ensure that our nation’s wine industry – from winegrape growers to winemakers and sellers – can continue to thrive and grow.”The Congressional Wine Caucus was founded in 1999 to educate Members of Congress on the many benefits and challenges of growing winegrapes and making wine. The Caucus hosts numerous events and policy briefings throughout the year designed to foster collaboration between policy makers and grapegrowers and winemakers with the goal of promoting a vibrant and sustainable American wine industry.
Wine Institute is the public policy advocacy association of nearly 1,000 California wineries and affiliated businesses working at the state, national and international levels to enhance the environment to responsibly produce, promote and enjoy wine. California wineries are responsible for 81% of U.S wine production and more than 90% of U.S. wine exports. They also contribute $114 billion annually to the U.S. economy and create 786,000 jobs across the country of which 325,000 are in California, bolstering economies through hospitality, taxes and tourism and enhancing communities through environmental and social sustainability. See: www.wineinstitute.org.
Thanks to the adequate rain fall within the past few months, winter planted dryland oats are being harvested, baled,and hauled for livestock feed. Wheat and alfalfa continue to mature. Forage crops will soon be ready to be cut forhay or silage Windy days will increase lodging in mature wheat fields which will cause issues at harvest. Groundpreparation is starting for spring forage and row crops. Cover crops are still being incorporated into the soil.
DECIDUOUS TREE FRUITS, NUTS, AND GRAPES:
Thinning of late variety stone fruit trees is ongoing. Immature stone fruit continues to develop. Early varieties ofapricots, plums, peaches, and nectarines have started with exports to Brazil. Cherry harvest has begun, with theTioga variety being picked for domestic markets. Reflective sheeting has been put out to aid in the fruit coloring forcherries. Yields for cherries this year look promising, weather permitting. Nutrient sprays and pesticide applicationsof fungicides and herbicides are starting for both vineyards and orchards. Mechanical vineyard maintenance isstarting with vine training. Leaf pulling in grapevines continues to allow for improved air circulation and lightpenetration around the developing bunches. Walnuts and pistachios are starting to bloom. Last season’s pistachionuts are being exported to the European Union, Turkey, China, New Zealand, Spain, and Vietnam. This season’salmonds are progressing nicely. Almonds from storage are being exported to India, Hong Kong, the Philippines,Japan, the Netherlands, Israel, Malaysia, South Africa, Korea, the United Kingdom, and Italy.
CITRUS, AVOCADOS, AND OLIVES:
Late Lane navel oranges are nearing the end of the season, with a moderate decline in fruit quality and demand. Fruitdrop and softening are becoming serious issues. Domestic and international exports for late navels are steady; withfruit being exported to Japan, China, Korea, Southeast Asia, Ecuador, and Mexico. Valencia oranges continue to bepicked and packed for both the domestic and international markets. International exports for Valencia orangescontinue to China, Japan, and Korea. As the Valencia season progresses, exports will intensify to internationalmarketplaces. Grapefruit harvest is nearing the end, but exports of Star Ruby grapefruit to Korea, Japan, and Mexicoare on-going. Seedless tangerine groves remain covered with nets to prevent pollination during the bloom period. Citrus grove mechanical maintenance is starting with trees being thinned, topped, and/or skirted. Some harvestedorange groves are being removed. Citrus bloom has been declared in all citrus groves around Tulare County. Lemonsare being harvested for domestic and overseas markets. Olive tree blooms are progressing.
VEGETABLES, MELONS, AND BERRIES:
Blueberries are being harvested, with exports being sent to Taiwan, Canada, and Japan. Blueberry harvest innorthern Tulare County should be starting within the next few weeks. Strawberry season is in full swing, withcontinuous bloom and mature fruit being picked for sale at roadside stands. Additional summer vegetable fields arenow being prepared for planting with warmer temperatures and ample soil moisture.
LIVESTOCK AND POULTRY:
Rangeland forage is in good quality condition, and mild rains have aided the new growth of grasses and forbs.Grazing conditions are good for local cattle ranchers. The fed cattle market is $126 per hundred-weight this week.
ADDITIONAL COMMENTS:
Local wholesale nurseries are gearing up for the spring rush, with shipments of nursery stock to both local and out-of-state nursery outlets. In preparation for Mother’s Day and balmier weather, retail markets are increasing theirinventory of annual and perennial flower and foliage plants. Bare-root roses continue to be processed but will soonhalt. Full sized olive trees are being removed from the ground and shipped for planting in ornamental landscapes.
End of the citrus bloom period for citrus grown in District 2 beginning at 1:00 a.m., Friday May 3, 2019.
WASHINGTON, April 30, 2019 — Agriculture Secretary Sonny Perdue announced today the availability of a new web-based tool – developed in partnership with the University of Wisconsin – to help dairy producers evaluate various scenarios using different coverage levels through the new Dairy Margin Coverage (DMC) program.
The 2018 Farm Bill authorized DMC, a voluntary risk management program that offers financial protection to dairy producers when the difference between the all milk price and the average feed cost (the margin) falls below a certain dollar amount selected by the producer. It replaces the program previously known as the Margin Protection Program for Dairy. Sign up for this USDA Farm Service Agency (FSA) program opens on June 17.
“With sign-up for the DMC program just weeks away, we encourage producers to use this new support tool to help make decisions on participation in the program,” Secretary Perdue said. “Dairy producers have faced tough challenges over the years, but the DMC program should help producers better weather the ups and downs in the industry.”
The University of Wisconsin launched the decision support tool in cooperation with FSA and funded through a cooperative agreement with the USDA Office of the Chief Economist. The tool was designed to help producers determine the level of coverage under a variety of conditions that will provide them with the strongest financial safety net. It allows farmers to simplify their coverage level selection by combining operation data and other key variables to calculate coverage needs based on price projections.
The decision tool assists producers with calculating total premiums costs and administrative fees associated with participation in DMC. It also forecasts payments that will be made during the coverage year.
“The new Dairy Margin Coverage program offers very appealing options for all dairy farmers to reduce their net income risk due to volatility in milk or feed prices,” said Dr. Mark Stephenson, Director of Dairy Policy Analysis, University of Wisconsin, Madison. “Higher coverage levels, monthly payments, and more flexible production coverage options are especially helpful for the sizable majority of farms who can cover much of their milk production with the new five million pound maximum for Tier 1 premiums. This program deserves the careful consideration of all dairy farmers.”
For more information, access the tool at fsa.usda.gov/dmc-tool. For DMC sign up, eligibility and related program information, visit fsa.usda.gov or contact your local USDA Service Center. To locate your local FSA office, visit farmers.gov/service-locator.
USDA extended the deadline to May 17 from May 1 for agricultural producers to certify 2018 crop production for payments through the Market Facilitation Program (MFP), which helps producers who have been significantly affected by foreign tariffs, resulting in the loss of traditional exports. USDA’s Farm Service Agency (FSA) extended the deadline because heavy rainfall and snowfall have delayed harvests in many parts of the country, preventing producers from certifying harvested production.
Payments will be issued only if eligible producers certify before the updated May 17 deadline.
The MFP provides payments to producers of corn, cotton, sorghum, soybeans, wheat, dairy, hogs, fresh sweet cherries and shelled almonds. FSA will issue payments based on the producer’s certified total production of the MFP commodity multiplied by the MFP rate for that specific commodity.
“Trade issues, coupled with low commodity prices and recovery from natural disasters, have definitely impacted the bottom line for many agricultural producers,” said FSA Administrator Richard Fordyce. “The MFP payments provide short-term relief from retaliatory tariffs to supplement the traditional farm safety net, helping agricultural producers through these difficult times. Weather conditions this fall, winter and early spring have blocked many producers from completing harvest of their crops, and we want to make sure producers who want to finalize their MFP application have an opportunity.”
U.S. Secretary of Agriculture Sonny Perdue launched the trade mitigation program to assist farmers suffering from damage because of unjustified trade retaliation by foreign nations. FSA implemented MFP in September 2018 as a relief strategy to protect agricultural producers while the Administration works on free, fair and reciprocal trade deals to open more markets to help American farmers compete globally. To date, more than $8.3 billion has been paid to nearly 600,000 applicants.
The MFP is established under the statutory authority of the Commodity Credit Corporation Charter Act and is administered by FSA.
Wawona Packing Company, a leading grower and shipper of organic and conventional tree fruit, today announced the start of its 2019 stone fruit season. Beginning with proprietary varieties of organic and conventional peaches and nectarines, the program will expand to include additional commodities and varieties as the season progresses with plums, pluots and apricots available by mid-May.
Wawona anticipates a large, promotable volume of stone fruit throughout its full 26-week season. Several of the varieties included in this year’s program are a result of the company’s acquisition of the stone fruit breeding assets of Burchell Nursery last summer.
“Our proprietary breeding program allows us to start earlier and finish later than our competitors, while maintaining exceptional quality throughout the season,” said Mark Berlinger, tree fruit sales manager at Wawona. “We always have had an extensive research and development program, and our partnership with Burchell Nursery has further expanded our ability to provide the most flavorful, high-quality varieties to our customers.”
With more than 9,000 acres of farmland in production in California’s central San Joaquin Valley, Wawona’s stone fruit program is the most diverse of its kind, offering organic and conventional varieties for yellow and white peaches, yellow
and white nectarines, black and red plums and pluots, along with conventional apricots.
For more information about Wawona Stone Fruit programs please call (559) 528-4000 or email sales@wawonapacking.com.
About Wawona Packing Company Founded in 1945, Wawona Packing Company currently farms more than 9,000 acres in California’s central San Joaquin Valley. Wawona offers organic and conventional tree fruit and citrus and is the largest grower of organic tree fruit in the United States. The company’s brands include Sweet-2-Eat, Sweet-2-Eat organic, Harvest Sweet and Wawona. For more information visit wawonapacking.com.
As climate change continues to threaten the state’s water infrastructure and reliability, Governor Gavin Newsom today signed an executive order directing his administration to think differently and act boldly by developing a comprehensive strategy to build a climate-resilient water system.
The order seeks to broaden California’s approach on water as the state faces a range of existing challenges, including unsafe drinking water, major flood risks that threaten public safety, severely depleted groundwater aquifers, agricultural communities
coping with uncertain water supplies and native fish populations threatened
with extinction.
“California’s water challenges are daunting, from severely depleted groundwater basins to vulnerable infrastructure to unsafe drinking water in far too many communities. Climate change magnifies the risks,” said Governor Newsom. “To meet these challenges, we need to harness the best in science, engineering and innovation to prepare for what’s ahead and ensure long-term water resilience and ecosystem health. We’ll need an all-of-above approach to get there.”
The order directs the secretaries of the California Natural Resources Agency, California Environmental Protection Agency and the California Department of Food and Agriculture to identify and assess a suite of complementary actions to ensure safe and resilient water supplies, flood protection and healthy waterways for the state’s communities, economy and environment.
The order directs the state to think bigger and more strategically on water by directing the agencies to inventory and assess current water supplies and the health of waterways, future demands and challenges. The agencies will seek input over the coming weeks and months through listening sessions, information workshops and other public meetings to help inform the water resilience portfolio that will be recommended to the Governor.
A copy of the order issued by Governor Newsom today can be foundhere.
Emission devices or emitters are vital component of drip/microirrigation systems as they control the dripping (emission) of water and fertilizer solution to the plant.Drip emitters basically slow down the flow rate to a “trickle” by dissipating the energy of the flow through frictional resistance.This makes it possible to deliver water and fertilizer solution to the plant in a frequent localized manner and at, essentially, constant rate; and that is the principal advantage of this method of irrigation.
Efficiency of a drip irrigation system refers to the ratio of the water delivered to the plant to satisfy its water requirements to the total applied water.High efficiency of a drip system is usually desired. Emission uniformity (EU) is a prerequisite for the high efficiency of the system as will be explained later.
Though drip systems are designed around EU, emission uniformity of the system is also influenced by the emitter selection.Therefore, the emitter should be selected prior to the initiation of the system design.Changing the emitter choice after completion of the design could degrade the system.Proper selection of emitter enables using smaller diameter laterals, longer laterals or less sub-main lines which means less costly system while maintaining the desired system uniformity and efficiency.
To help you select the appropriate emitter, a discussion of emitters flow characteristics are presented followed by a description of some of the commonly used types of emitters.A guideline for emitter selection is then provided.
Emitter Flow Characteristics
Drip emitters regulate water flow by dissipating the flow energy through frictional resistance.Laminar flow emitters regulate water flow by dissipating energy via friction against the walls of long and narrow path.Microtubes and spiral path emitters are examples of laminar flow emission devices.
On the other hand, turbulent flow emitters regulate water flow by dissipating energy by friction against the walls of the water passage and also between the particles themselves during their turbulent movements.Orifices, nozzle emitters, tortuous path emitters and jets or sprayers are typically turbulent emitters.The drip tapes that utilize orifices are also turbulent flow devices.
Laminar Flow Emitters
In a laminar flow the fluid particles move along parallel paths in layers or laminas.The magnitude of the velocities of adjacent laminas is not the same and liquid viscosity (i.e., resistance to poring) is dominant in controlling liquid movement and suppresses any conditions that may cause turbulence.
Hydraulic investigations showed that in a laminar flow, the flow rate “Q” of the emitter is directly proportional to the operating pressure and a change in operating pressure will produce an equal percentage of change in flow rate, i.e., if (H1/H2) = 1.1, then (Q1/Q2) = 1.1, and a change of 10 percent in operating pressure would result in a change of 10 percent in flow rate.
Therefore, the flow rate through laminar flow emitters is pressure sensitive (i.e., less pressure compensating, see turbulent flow emitters below).It is also temperature sensitive since it is influenced by the changes in viscosity of water which changes with temperature, i.e., the higher the water temperature the lower the water viscosity and the larger the discharge rate Q.Laminar flow emitters are also more susceptible to clogging because of their low flow velocity and their relatively long and narrow flow path.However, laminar flow emitters are inexpensive and with proper system maintenance will have satisfactory performance.These emitters are more suitable for short run laterals, where head loss is not very large and flow rate would not suffer large change between emitters.
Turbulent Flow Emitters
In turbulent flow the particles of the fluid moves in a haphazard fashion in all directions.While the viscosity is dominant with laminar flow, both inertia (that property of matter because of which a force must be exerted on a body in order to accelerate it) and viscosity affect the turbulent flow pattern.
Therefore, for turbulent emitters hydraulic investigations showed that the flow rate Q will vary with the square root of the operating pressure H, i.e., Q1/Q2 = [H1/H2]1/2 , and a change in operating pressure H of 10 percent would produce a corresponding change in flow rate Q of only 5 percent, i.e., if[H1/H2] = 1.10, then Q1/Q2 = [H1/H2]x = [H1/H2]1/2 =1.05.Thus, turbulent flow devices are less sensitive to pressure variations (more pressure compensating) than laminar devices, i.e., the same pressure change will produce much smaller change in discharge rate with turbulent flow emitters than with laminar flow ones.
The practical application of this conclusion is that if all other factors being equal, the length of laterals for turbulent drip tape for a given design uniformity could be longer than those of laminar drip tape while maintaining the same desired value of EU.Where the length of the lateral line is fixed (e.g., by field dimensions) the use of turbulent drip tape, for instance, will result in higher uniformity than laminar one due to less flow rate variation with turbulent flow.Hydraulic investigations also showed that the flow rate, Q, with turbulent flow emitters is independent of viscosity and therefore it is much less affected by water temperature than laminar flow emitters.Moreover, the flow path of the turbulent emitters is wider than that of the laminar flow ones which make them less susceptible to clogging than the laminar flow emitters.
Discharge Exponent, x
The exponent “x” mentioned above is usually referred to as the “discharge exponent”.The value of this exponent is usually close to unity (≈ 0.7 – 0.8) for laminar flow emitters and about 0.5 – 0.6 for turbulent flow emitters.
Coefficient of Variation, Cv
Manufacturing variability is a common industrial phenomenon where no two items are made exactly the same particularly for items of very narrow internal passages such as drip emitters.A minute change in the dimension of these passages could make a significant difference in the emitter discharge rate especially the pressure compensating ones.The coefficient of manufacturing variability for the emitter (Cv) is used as a measure of expected variations in discharge of new emitters from the average discharge, qa, of a particular sample of the given emitters when operated at a constant pressure head.Usually, emitter manufacturers provide the values of Cv for their products.
The discharge rate of representative sample of emitters operating at a given pressure essentially follows a bell-shaped normal distribution curve. Where qais the average emitter discharge, approximately 68 percent of the discharge rates fall within (qa ± Cv) , 95 percent of the discharge rates fall within (qa ± 2 Cv), and 99.7 percent of the discharge rates fall within (qa ± 3 Cv).
This means that for Cv values of 10% (0.10)samples of emitters with qaof 1gph, 68 percent of emitter discharge rate would fall within the discharge range of (qa ± Cv) or0.9 to 1.1 gph, 95% percent of emitter discharge rate would fall within the range of (qa ± 2 Cv) or 0.8 to 1.2, and 99.7 percent of emitter discharge rate would fall in the range of (qa ± 3 Cv) or 0.7 and 1.3 gph respectively.
Also for Cv values of 5% (0.05) samples of same emitters. 68 percent of discharge rate would fall within the discharge range of (qa ± Cv) or 0.95 to 1.05 gph, 95% of discharge rate would fall within the range of (qa ± 2 Cv) or 0.9 to 1.1, and 99.7 percent of discharge rate would fall in the range of (qa ± 3 Cv) or 0.75 and 1.25 gph respectively.
Therefore, the smaller the Cv value of a given sample of emitters the less different, or the more uniform, is the sample and the better the emission uniformity (EU) of water in the field.Table 1 provides the ranges and the common evaluations (classification) of Cv values.
Table 1. Coefficient of manufacturer variability, Cv
A higher Cv values, is used for line-source tubing because it is difficult to keep Cv and price both low.However, because line-source outlets are usually closely spaced the effect of higher Cv value on discharge uniformity is minimized.
Emission Uniformity, EU
Emission uniformity (EU) is a critical characteristic around which drip irrigation system is designed.EU indicates how uniform the system applies water in the field.High EU is a prerequisite for high efficiency.Irrigation efficiency could be expressed as how much of the applied water is added to the plant root zone.
It is not possible to acquire high efficiency with low uniformity, EU, because with low uniformity higher percentage of the field area will receive either less water or more water than the average application needed to satisfy the crop water requirements.To remedy this deficiency more water will need to be applied to the field to satisfy the requirements of the under-irrigated parts of the field.This will result in over-irrigating the rest of the field and that means more water is lost away from the root zone resulting in lower irrigation efficiency.
With high EU, only small percentage of the field will be under-irrigated and the volume of water needed to provide for the under-irrigated parts of the field will be much smaller, the losses will be smaller as well, therefore, the efficiency will be higher.However, it is possible to have a low efficiency with high EU.This is not contradictory to what was previously stated that high EU is a prerequisite for high efficiency. For example, if high EU is achieved in a field but excessive amount of water is applied to that field by applying irrigation water for much longer period of time than scheduled for delivering the estimated water requirements of the crop (i,e., over-irrigation) then, large amount of water will be lost away from the root zone and the irrigation efficiency will be low despite the achieved high EU.
Fig. 1. Typical layout of a microirrigated system
B:Types of Emitters
Emitters are usually grouped according to their flow patterns (e.g., laminar and turbulent flow), wetting patterns (e.g., point-source, line-source, multi-exit emitters), and special functions (e.g., pressure compensating and flushing emitters).Some emitters may combine more than one attribute, e.g., pressure compensating line-source emitter (drip tape).
Flow Pattern
* Laminar & Turbulent Flow Emitters
Turbulent flow emitters have the advantage of being less sensitive to pressure variation (i.e., more pressure compensating), less sensitive to water temperature variations, less susceptible to clogging and allow for longer lateral runs or less pressure variation for the same length of lateral run than laminar flow emitters.Laminar flow emitters are less expensive and more suitable for short-run laterals.On-line, in-line and drip tape come in either laminar or turbulent flow type.Both laminar and turbulent flow emitters may come in standard or pressure compensating type.
Wetting Pattern
*Point-Source and Line-source emitter
Drip irrigation with water discharged from emission points that are rather widely spaced, usually 3 ft or more, is commonly referred to as point-source application.When water is discharged from more closely spaced outlets it is called line-source application.Examples of point-source is on-line and in-line emitters (see Fig’s. 2 & 3).The most common discharge rate of point-source emitters is 1 gph.Other available sizes are 0.5, 1.5, 2.0 gph.Point-source emitters come in standard and pressure compensating models.
On-line emitters are commonly used for irrigating orchards and vineyards.The PE (polyethylene) laterals are usually laid on the ground surface (see Fig. 2).This type of emitters offers the user the advantage of installing an emission device exactly where wanted and the emitters are serviceable.Their disadvantage is that the end user must manually insert each emitter.
In-line emitters or drip lines are similar to on-line emitters but in this configuration they are pre-inserted into the PE tubing at specified intervals during the tubing extrusion process (see Fig. 3).The emitters may be cylindrical or flat “boat shaped”, and are attached to the inner tube wall via a controlled heating/adhesion process.Labor savings for the end user may be substantial since emitters are factory pre-installed.The drawback is that emission devices may exist where not needed, and they are not serviceable. Drip-line may be installed below the surface such that the soil surface may be kept dry.Both on-line and in-line emitters come in regular and pressure compensating types.
Examples of line source are single chamber and double chamber drip of relatively thin tubing, commonly known as “drip tapes” (see Fig. 4).Single chamber tubing has orifices punched or more complex emitters fabricated or inserted at intervals of 2 ft or less along the tubing.Double chamber tubing is a hose that has both a main and auxiliary bore separated by a single wall.Widely spaced inner orifices are punched in the separator wall between the main and the auxiliary bore; for each inner orifice, three to six exit orifices are punched at intervals of 0.5 to 2 ft in the outer wall of the auxiliary bore.
Drip tape may be classified according to their flow pattern as either turbulent or laminar.Turbulent drip tape controls flow rate by means of orifices or tortuous flow paths, while laminar tape utilizes small tubes or capillaries to control flow rate.These two types of drip tape exhibit different flow rate response to pressure variation (as explained earlier) and they are not mutually exchangeable for the purpose of system design.
Water is distributed evenly along the length of the drip tape through emission devices that may be spaced anywhere from 4” to 24” apart.Tube wall thicknesses vary from .004” to .015” (4 mil to 15 mil), emitter flow rates from 0.07 to 0.34 gph, and tube diameters from 5/8” to 1-3/8”.Drip tape is used extensively for irrigating vegetable and field row crops e.g., strawberries and tomatoes.It may be installed above or below the ground, and may be retrieved for multi-season reuse or disposed of at the end of each season.Drip tape is relatively inexpensive and is ready to install without any additional emission device installation labor.
*Sprayer, Jets or microsprinklers(see Fig. 7 & 8)
These are small applicators designed to spray water to cover an area of 10 to 100 ft2.Jets are mounted on risers or stakes (see Fig. 8) and spray water through the air as separate streams that create various foot printpatterns of water in the soil.A variety of patterns are available including full circle, half circle, hi/low trajectory, butterfly, etc.The versatility of patterns provides a great deal of flexibility for the end user to accurately apply water only where wanted, such as enveloping each tree in an orchard without wetting the trunk.Wetted diameter ranges from 10 to 35 ft and discharge rate from 5 to 30 gph.Flow through jets is turbulent with discharge exponent x = 0.5.Jets are commonly used on orchard crops like almond and citrus and on light textured soils.
Special Function
*Pressure-Compensating Emitters
This type of emitters provides varying degree of flow regulation with discharge exponent “x” value ranging from 0.0 to 0.4.For complete flow regulation x = 0.0.Pressure compensating devices may be either laminar or turbulent.In either case, these devices utilize the inlet pressure to modify the flow path size, shape or length.In this way, pressure-compensating devices are able to deliver the correct flow rate over a fairly wide range of inlet pressures, and within that range their flow rates are relatively constant.Pressure-compensating emitters are useful for use in undulating fields.
Pressure compensating emitters suffer from the drawback that the elastomeric material used in their construction has a tendency to change their properties as they age. The following graphs (Fig’s. 9 & 10) show the difference in performance between pressure-compensating and non pressure-compensating emitters.
*Flushing Emitters
This type of emitters is designed to have a flushing flow of water to clear the discharge opening every time the system is turned on.Continuous flushing emitters permit continuous passage of large solid particles whileoperating.Some on-line emitters and drip tape are manufactured with flushing capabilities.
*Multi-Exit Emitters(see Fig. 6)
Some on-line emitters supply water to two or more points through small diameter auxiliary tubing; they are used in orchards where large trees may require several emission points for each tree.They are usually more expensive than single exit emitters.
E.A Guideline for Emitter Selection
The pressure variation within the system and the flow characteristics of the selected emission devices influence the uniformity of water distribution (EU) of a drip/microirrigation system.While the control of pressure variation by proper system design is certainly required, the selection of the emitter device itself is also vital for achieving the desired high EU and high system efficiency (e.g., x & Cv).Moreover, emitter selection is critical for specifying the water treatment and the filtration equipment for the drip system.Filtration requirement for a given emitter is specified by the emitter manufacturer.User preference might also be a factor and personal and local experience may influence the choice of emitter.
However, two very important items to be considered in emitter selection are the percentage area wetted, which is related to delivering the required amount of water to the plant at the design pressure, and the reliability of the emitter against clogging and malfunctioning.
It is recommended to provide a sufficient number of emission points to wet between one-third and one-half of the horizontal cross sectional area of the potential root-zone.Field observations have shown that the density of emission points required to obtain such percentage of wetting can be based on an assumed discharge of 1 gph emitters.For perennial crops, the number of emitters can be increased with the age of the plant and stage of growth.However, the initial pipe network must be designed to meet the needs of the mature plants.It is usually recommended that the filtration process should remove all particles larger than one-tenth the diameter of the emitter passage way.Also, regular flushing of laterals can significantly reduce emitter clogging (see Fig. 11).
Conclusion
Generally, the selection of an emitter depends on the soil to be wetted, plants to be grown and their water requirements, quality of irrigation water and emitter discharge. The cost ofemitter should be also be considered as the average total cost of emitters may amount to about 20-25 percent of the total cost of the system.The following points together with above provided explanations may provide a guideline for emitter selection.
First determine the general type of emitter that best fits the needs of the crop to be irrigated and the area to be wetted, i.e., continuous wetting pattern for vegetable crops where a drip tape could be suitable, on-line emitters for irrigating orchard crops,jets where relatively coarse textured soil prevails or where light water applications with large foot print could be more suitable for the crop requirements.The use of pressure compensating emitters may be advantageous for undulating terrain.
Second, according to the required discharge, spacing, and other field conditions, choose the specific emitter needed, i.e., which drip tape, jet pattern, or on-line emitter could be more fitting for supplying the water requirements of the crop, e.g.,for drip tape, is it going to be for one season, 4 mil, or for several seasons, 25 mil.Third, determine the required discharge (q) and operating pressure head (H) for the average emitter that fits the system design and prevailing conditions (e.g., water quality, soil properties, weather conditions).
It is also important to examine the emitter characteristics described above i.e., x, Cv, filtration requirements.Emitters with discharge exponent (x) closer to 0.5 is more pressure compensating, less sensitive to temperature changes and less susceptible to clogging than the ones with the value of x closer to one. The smaller the Cv value for the emitter the more uniform is water application in the field.Emitters with Cv between 0.03 to 0.05 are expected to provide higher EU and consequently higher system efficiency than the ones with Cv between 0.07- 0.09.
Filtration requirement as stated by the emitter manufacturer should also be considered, the smaller the required mesh number (number of opening per inch) the less susceptible the emitter to clogging.Emitters that require mesh number 160 is less susceptible to clogging than the ones that requires 260 mesh number for filtration.However, the filtration requirements as stated by the emitter manufacturer should be fulfilled.Also, enquire with emitter manufacturers regarding the tolerance of emitter components to chemicals such as acid and chlorine usually used for system cleaning and disinfection.Finally, local and personal experience should be taken into consideration.
For more information, visit www.agridrip.com or contact F.A.Hassan, an irrigation & Soils Consultant at Agro Industrial Management at “fahassan@aol.com“
USDA’s National Agricultural Statistics Service (NASS) reports that California’s almond acreage continued to increase in 2018. Bearing acres, or orchards that have matured enough to produce a crop, are reported at 1.09 million acres, which is up 6 percent from 2017. Total almond acres for 2018 is estimated at 1.39 million acres, up 2 percent from the previous year.
With this increase, almond growers remain committed to continuous improvement, finding ways to responsibly produce more almonds to meet global and domestic demand (30% of total shipments of California almonds are shipped domestic). Last year, the Almond Board of California (ABC) Board of Directors prioritized industry resources in four key areas that will ensure almonds remain as leaders in California agriculture as they work towards producing an economically, environmentally and socially responsible crop. These four key areas – water use, harvest dust reduction, environmentally friendly pest management, zero waste – ladder up to the Almond Orchard 2025 Goals, whichbuild upon a history of significant industry achievements. For example, over the past two decades growers have reduced the amount of water it takes to grow a pound of almonds by 33%.
In addition to achievements in the orchard, on the processing side there have been zero outbreaks of foodborne illness attributed to California almonds since the rollout of a groundbreaking pasteurization program a decade ago. In fact, earlier this month the Almond Board was selected to receive the GMA Food Safety Award from the International Association for Food Protection, in recognition of the Board’s “preeminence in and contributions to the field of food safety.”
“The California almond industry continues to prove itself as a leader in responsible practices, from the orchard to the processor,” said Almond Board President and CEO Richard Waycott. “The Almond Orchard 2025 Goals act as a guidepost on our journey towards continued advancement and innovation throughout the industry. With the latest acreage numbers, we’re confident in our ability to continue to meet global demand and to provide the world with a high-quality product.”
On Friday, May 10, 2019, NASS will release the 2019 Subjective Report, which provides an initial forecast of the upcoming crop. Data for the Subjective Report is based on opinions obtained from almond growers in a survey sent by NASS. Almond growers will soon receive the NASS survey and are encouraged to participate. For more information, growers may contact Bryce Spycher at bspycher@almondboard.com.
About the Almond Board of California
California Almonds make life better by what we grow and how we grow. The Almond Board of California promotes natural, wholesome and quality almonds through leadership in strategic market development, innovative research, and accelerated adoption of industry best practices on behalf of the more than 6,800 almond farmers and processors in California, most of whom are multi-generational family operations. Established in 1950 and based in Modesto, California, the Almond Board of California is a non-profit organization that administers a grower-enacted Federal Marketing Order under the supervision of the United States Department of Agriculture. For more information on the Almond Board of California or almonds, visit Almonds.com or check out California Almonds on Facebook, Twitter, Pinterest, Instagram and the California Almonds blog.
The National Onion Association’s membership works hard to keep their operations sustainable. From use of onion as a raw “onion power” to power up facilities to protecting workers and the land, America’s onion farmers work hard every day to create the most sustainable programs possible. It’s not only right for the country, but their families as they continue to feed America. This Earth Day, remember the onion farmer, and his/her contributions, to keeping the Earth healthy, while they help feed America.
Here are some great examples of sustainable practices in the onion world:
“Onion Power”
Ten years ago, Gills Onions in California created a system whereby it uses onion remains (tops, skins, stems and tops) to create energy, a system that now has generated more than 25 gigawatt hours of electricity — enough power to supply a year’s worth of power to 460 residential homes. The Advanced Energy Recovery System provides 100 percent of the base electrical load of Gills’ processing plant in Oxnard, Calif. Gills to this day is working to achieve greater efficiency and energy independence.
“It’s hard to do business in California, but also it challenges us to think outside of the box. So, onion juice power was (owner Steve Gill) thinking outside of the box. He created a program that did not exist in the world.”
Our farmers continue to close in on the idea of zero waste. There are continually new ways of using all of the onions. From the tops and stems in production facilities, to the “culls” left over in the field being used for sheep feed, and shredded for cattle crazing.
• Sakata Farms in Colorado routinely trucks its culls to area sheep farms.
• Fashion designers in New York are using onion skins as natural dyes for their fabrics. A group of students working with the Fragmentario studio in New York City will unveil its onion fabrics during NY Textile Month in September. (Contact: Maria Elena Pombo, Fragementario Studio, https://fragmentario.co/)
• Gumz Farms in Endeavor, Wis., has installed a high-tech, humidity and temperature controlled circulation system, which allows it to store onions longer, reducing waste. Gumz also is a member of the Healthy Grown program in Wisconsin, which ensures their commitment to sustainability.
Coveting the land
America’s onion farmers work diligently to keep soils healthy to grow the best products to put on the table. They follow researchers from around the world to implement the best practices.
Says Dylan Dembeck of Minkus Family Farms in New York:
“Many people think commercial agriculture hurts the land, but they don’t realize it is in our best interest to keep the land as fertile as possible to continue to produce high quality produce for generations to come. Not only are sustainable farming techniques good the for environment it is also very good for farmers. We are able to achieve higher yields, better quality product, and decrease our overall chemical applications. These things are all better for the environment and they help farmers increase their bottom line to ensure they can continue to farm for many years to come.”
• At Potandon Produce in Idaho, soil ph and nutrient levels are constantly monitored to reduce fertilizer use.
Reducing footprints
• Minkus Family Farms in New York has installed solar panels to reduce its footprint; it has built 62 skylights in their warehouse, almost completely eliminating the need for lighting in tis warehouse. Use exclusively LED lights. It also uses 10 large 20-foot fans to reduce building temperature, to avoid as much air conditioning as possible.
• Potandon Produce in Idaho also recycles fresh water in an overall water management plan, uses poly bags printed with water-based inks and uses only recycled materials in its master containers. Corrugated and cardboard containers are sourced from suppliers that are part of the Sustainable Forestry Initiative Program.
• Grimmway Farms in California has a 4.75 megawatt solar from to help power its facilities, along with a multifaceted sustainability program to reduce its footprint.Water management and soil protection
• Fagerberg Farms in Eaton, Colo., uses subsurface drip irrigation, an innovative watering practice that requires less water, fewer chemicals and more efficient applications. Fagerberg has been recognized in the farming industry for its sustainable farming practices.
• In Glennville, Ga., G&R Farms constantly monitors its varieties to get the best yields with the greatest efficiencies. Part of that is water management.“On the field side, we try to be very protective of the water, and make sure we don’t have any washing in the field or erosion. We put in cover corps in the off season to protect the till for the soil. Our goal is to use less and less fertilizer,” said Cliff Riner of G&R Farms. “We have to stay on top of the curve to provide the best product we can.”
The National Onion Association was incorporated in 1913 and represents more than 500 onion growers, shippers, packers and suppliers throughout the United States.
Wawona Packing Company, a leading grower and shipper of organic and conventional tree fruit, today announced the start of its 2019 stone fruit season. Beginning with proprietary varieties of organic and conventional peaches and nectarines, the program will expand to include additional commodities and varieties as the season progresses with plums, pluots and apricots available by mid-May.
