Among the many challenges facing the agricultural community, communication is among the most important. Recent water shortages have raised the attention of the public to agriculture and specifically crop production systems in the desert Southwest. This has revealed an enormous lack of knowledge on the part of the non-agricultural public about the process of crop production and the management required to produce crops successfully and sustainably in the desert. As it is commonly stated: “Facts may be facts, but perception becomes reality.”
Dwight D. Eisenhower once said, “Farming looks mighty easy when your plow is a pencil and you’re a thousand miles from the cornfield.” We have certainly seen these tendencies in action during the past few years with an abundance of well-intended advice and directions from the non-ag public regarding how farmers and agricultural entities should deal with the water shortage.
Part of our challenge in working with people from non-ag or urban sectors is communicating some basic facts and the truth about agriculture. This challenge is compounded by the abundance of misinformation, the tendency for people to consider these issues emotionally as opposed to rationally, and the associated lack of interest many people have in hearing about statistics and science-based information. So, the challenge in communication is often centered on some basic foundational points and trying to make it relevant to people.
Most of the time in communicating agricultural perspectives to urban or non-ag audiences we are working with people who are several generations removed from agriculture. In 1900, nearly 40% of the U.S. population worked on farms and ranches and 60% lived in rural areas. Today, those numbers are only 1% and 20% (Figure 1). Considering that, it is easy to understand the disconnect we commonly experience between agricultural realities and common perceptions in the urban sectors.
Even with less people working in agriculture, crop yields have continued to increase (Figure 2). For example, contrasting crop yields in U.S. from 1900 to 2014 shows that corn yields in 1900 were only 18 % of what they were in 2014. Similarly, 1900 wheat yields were only about 30 percent of what they were in 2014. This has been largely due to the adoption of improved mechanization, synthetic fertilizers, improved genetics, and seed quality. Also, crop yields have been better protected with integrated pest management systems for the management of insects, weeds, and diseases. Major increases in crop yields have been particularly realized since World War II. The irony is that all these factors contributing to higher yields are commonly the points of fierce criticism from the non-ag populace.
Simple things like the significance of photosynthesis and the capture of light energy from the sun with water from the soil and carbon dioxide (CO2) from the air and then converted into the plant dry matter that humans and other animals consume and depend on for survival is a connection not made by most people. The process of photosynthesis and how we manage it is really a fundamental piece of our agricultural foundations. It also describes the basic relationship of water to crop production. We cannot assume that people understand even these basic facts.
In production agriculture we are dependent on natural resources, such as water, climate, and the soils of this region. In the desert Southwest, our capacities to produce the highest crop yields of anywhere on the planet with premium quality products is largely a function of the dry climate, our capacity to provide sufficient water by irrigation, and the utilization of the tremendous resources of geologically young and highly fertile soils.
Another critical resource that is essential to the crop production systems of the desert Southwest is the skill and expertise provided by the people who are farming and managing these systems. In my work with the University of Arizona over the past 36 years, I have had the opportunity to work with people in crop production regions in many parts of the world, commonly in arid and semi-arid regions. I am always impressed with the skill, commitment, and capacity of farmers all over the world. But the skill levels required to survive and compete in crop production systems in the desert Southwest are unsurpassed.
Farmers and the full array of personnel including technicians, pest control advisors, agronomists, irrigators, farm operators, business managers, mechanics, etc. are essential in the production of crops. Successful crop management requires the successful integration of all these components and much more. Improvements in our systems of crop production include our constant efforts to improve efficiency in the integration of these essential components.
Crop production efficiency comes in at least three different forms: economic, agronomic, and environmental. These three aspects of crop production efficiency are all important and they can be met simultaneously, but economic survival is essential, and it becomes first and foremost in the management of a farming operation. If a farm is not profitable it does not survive.
A tremendous amount of technical knowledge and skill is required in crop production and an effective understanding and application of scientific knowledge is essential. Beyond the scientific capabilities required, there is also a high degree of skill required to manage and effectively integrate everything into a crop production operation. Thus, it is a fact that crop production is a combination of art and science.
Effectively communicating agriculture and basic facts about food production is a real challenge for those of us working in agriculture. As we have seen recently with the challenges that we have faced with the water shortages, the survival of agriculture crop production systems in the desert Southwest will be dependent at least in part upon our capacity to effectively communicate to the non-ag or urban sectors of our state, region, and nation.
The manner of this communication is one of our grand challenges for current and future sustainability of agriculture in the desert Southwest. I find this to be a challenge within the university community and even within a college of agriculture. It is not always easy but it is important for all of us in the agricultural community to understand and engage in this effort to communicate appropriately with our fellow citizens in non-ag and urban sectors when given the opportunity. We have a lot at stake and we are all in this together.
A broad separation between public perception and reality exists and it is important to understand that. Perhaps these water shortage situations can serve as a platform for improving public knowledge of agriculture and crop production.
This study was conducted at the Yuma Valley Agricultural Center. The soil was a silty clay loam (7-56-37 sand-silt-clay, pH 7.2, O.M. 0.7%). Spinach ‘Meerkat’ was seeded, then sprinkler-irrigated to germinate seed Jan 13, 2025 on beds with 84 in. between bed centers and containing 30 lines of seed per bed. All irrigation water was supplied by sprinkler irrigation. Treatments were replicated four times in a randomized complete block design. Replicate plots consisted of 15 ft lengths of bed separated by 3 ft lengths of nontreated bed. Treatments were applied with a CO2 backpack sprayer that delivered 50 gal/acre at 40 psi to flat-fan nozzles.
Downy mildew (caused by Peronospora farinosa f. sp. spinaciae)was first observed in plots on Mar 5 and final reading was taken on March 6 and March 7, 2025. Spray date for each treatments are listed in excel file with the results.
Disease severity was recorded by determining the percentage of infected leaves present within three 1-ft2areas within each of the four replicate plots per treatment. The number of spinach leaves in a 1-ft2area of bed was approximately 144. The percentage were then changed to 1-10scale, with 1 being 10% infection and 10 being 100% infection.
The data (found in the accompanying Excel file) illustrate the degree of disease reduction obtained by applications of the various tested fungicides. Products that provided most effective control against the disease include Orondis ultra, Zampro, Stargus, Cevya, Eject .Please see table for other treatments with significant disease suppression/control. No phytotoxicity was observed in any of the treatments in this trial.
There are many innovative automated weeding technologies coming out of Europe. One of these is ARA, the high precision, smart spot sprayer being developed by Ecorobotix[1] (Yverdon-les-Bains, Switzerland). Early prototypes were solar powered, autonomous robots that used a spider-like, three-axis delta robot to precisely deliver herbicides to target weeds (Fig. 1). The company has since moved on to a much simpler solution – a fixed boom, tractor pulled implement (Fig. 2). The 19.7’ wide smart sprayer is equipped with 156 individually controlled spray nozzles spaced 1.6” resulting in a spot spray resolution of 5.6 inch2 (2.4 x 2.4 inch). The claimed travel speed is 4.5 mph equating to a work rate of 10 ac/hr. The machine uses computer imaging and artificial intelligence for crop/weed differentiation to identify and target weeds. AI weeding models have been developed for a variety of crops including several vegetable crops – onion, lettuce and spinach. In addition to weed control, the smart sprayer can be used to spot apply beneficial products to only the crop plant. A company video showing the device operating in onion crops can be found by clicking here or on the image below.
As I have mentioned before, robotic and automated weeding technologies are advancing at a very rapid pace. If you know of a new technology that would be of interest and appropriate for this newsletter, please feel free to contact me.
Fig. 1. Solar powered autonomous weeding robot developed by Ecorobotix,
Switzerland. The unit is equipped with three-axis delta robot arms to precisely
deliver herbicides to target weeds (Photo credit – Ecorobotix).
Fig 2. Precision weeding machine developed by Ecorobotix, Switzerland. The unit
is equipped with individually controllable spray nozzles mounted on a 19.7’ wide
spray boom to spot spray weeds (Photo credit – Ecorobotix).
Fig. 3. Precision spray boom comprising 156 spray nozzles for spot spraying
weeds. Spot spray resolution is 2.4 x 2.4 inches. (Photo credit – Ecorobotix,
Switzerland).
[1] Reference to a product or company is for specific information only and does not endorse or recommend that product or company to the exclusion of others that may be suitable.
Growers and PCAs asked about the potential injury that can be caused by a mix of RoNeet (Cycloate) with Dual Magnum (S-Metholachlor) to spinach. We did a small evaluation including the treatments suggested by our friends to collect data. A 1.33pt rate for Dual M and 4.0 pt of RoNeet was sprayed for this trial. The lower Dual M recommended rate by the SLN for AZ in 2017 of 0.33 - 0.67 pt per acre was not included in the trial1. Here’s the treatment list:
Plots consisted of two rows 30ft long replicated four times with 10 seed lines, and the test was established in a randomized complete block design with four replications. All treatments were applied preemergence. A CO2 backpack with a 4 flat fan nozzle boom spaced at 20” was used delivering 20 gallons/acre.
Planting was done on Nov 17, 2022, then the next day the treatments were applied and incorporated immediately with sprinkler irrigation. Crop injury was evaluated on December 13, 21 and 27. The combination of RoNeet plus S-Metolachlor at the rates above mentioned presented the highest phytotoxicity symptoms in the form of chlorosis, stunting, and reduced stand. Also, Dual Magnum alone at the rate of 1.33 pt/a presented injury in lower proportion compared to the combination with RoNeet. In this evaluation the 4pt/a rate of RoNeet did not present injury to the spinach as you can see comparing with the untreated plots below. Weed control data was not collected due to inconsistent and low populations. Only phytotoxicity was evaluated.
The most representative images of the plots are below:
Figure 1. Preemergence herbicide injury evaluation on spinach
Results of pheromone and sticky trap catches can be viewed here.
Corn earworm: CEW moth counts down in all traps over the last month; about average for December.
Beet armyworm: Moth trap counts decreased in all areas in the last 2 weeks but appear to remain active in some areas, and average for this time of the year.
Cabbage looper: Moths increased in the past 2 weeks, and average for this time of the season.
Diamondback moth: Adults increased in several locations last, particularly in the Yuma Valley most traps. Below average for December.
Whitefly: Adult movement remains low in all areas, consistent with previous years
Thrips: Thrips adult movement continues to decline, overall activity below average for December.
Aphids: Winged aphids still actively moving but declined movement in the last 2 weeks. About average for December.
Leafminers: Adult activity down in most locations, below average for this time of season.
