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The complexity of implementing site-specific decision support tools

How scientists can help bridge the technology gap

In our latest We Measure the World podcast, we interview Oregon State University researcher Dalyn McCauley 

about her experience developing a site-specific decision support tool for on-farm management of crop damaging weather events—and techniques she used to help the grower implement changes for quality and yield improvements.

Listen now

Webinar Series: Irrigation of Controlled Environment Crops for Increased Quality and Yield

Part 1: Substrates and Water

Stop guessing. Start measuring.

When you irrigate in a greenhouse or growth chamber, you need to get the most out of your substrate so you can maximize the yield and quality of your product.

But if you’re lifting a pot to gauge how much water is in the substrate, it’s going to be difficult—if not impossible—to achieve your goals. To complicate matters, soil substrates and potting mixes are some of the most challenging media in which to get the water exactly right.

Without accurate measurements or the right measurements, you’ll be blind to what your plants are really experiencing. And that’s a problem, because irrigating incorrectly will reduce yield, derail the quality of your product, deprive the roots of oxygen, and increase risk of disease.

Supercharge yield, quality—and profit

At METER, we’ve been measuring soil moisture for over 40 years. Join Dr. Gaylon Campbell, founder, soil physicist, and one of the world’s foremost authorities on soil, plant, and atmospheric measurements, for a series of irrigation webinars designed to help you correctly control your crop environment to achieve maximum results. In this 30-minute webinar, learn:

  • Why substrates hold water differently than normal soil
  • How the properties of different substrates and potting mixes compare
  • Why it’s difficult if not impossible to irrigate correctly without accurately measuring the amount of water in the substrate
  • The fundamentals of measuring soil moisture: specifically water content and electrical conductivity
  • How measuring soil moisture helps you get the most out of the substrate you choose, so you can improve your product
  • Easy tools you can use to measure soil water in a greenhouse or growth chamber to maximize yields and minimize inputs

Watch it now—>

The complete guide to irrigation management using soil moisture

Irrigation management: Why it’s easier than you think

Years ago, we received an irrigation management call from a couple of scientists, Drs. Bryan Hopkins and Neil Hansen, about the sports turfgrass they were growing in cooperation with the Certified Sports Field Managers at Brigham Young University (BYU) and their turfgrass research and education programs. They wanted to optimize performance through challenging situations, such as irrigation controller failure and more. Together, we began intensively examining the water in the root zone. 

BYU researchers are zeroing in on irrigation management best practices leading to better outcomes that are easier to achieve.

As we gathered irrigation and performance data over time, we discovered new critical best practices for managing irrigation in turfgrass and other crops, including measuring “soil water potential”. We combined soil water potential sensors with traditional soil water content sensors to reduce the effort it took to keep the grass performance high, while saving water costs and reducing disease potential and poor aeration. We also reduced fertilization costs by minimizing leaching losses out of the root zone due to overwatering.

Supercharge yield, quality and profit in any crop with soil moisture-led irrigation management 

This article uses turfgrass and potatoes to show how to irrigate using both water potential and water content sensors, but these best practices apply to any type of crop grown by irrigation scientists, agronomists, crop consultants, outdoor growers, or greenhouse growers. By adding water potential sensors to his water content sensors, one Idaho potato grower cut his water use by 38%. This reduced his cost of water (pumping costs) per 100 lbs. of potatoes, saving him $13,000 in one year. But that’s not even the best part. His yield increased by 8% and he improved his crop quality—the rot he typically sees virtually disappeared.

What is soil water potential?

In simple terms, soil water potential is a measure of the energy state of water in the soil. It has a complicated scientific definition, but you don’t have to understand what soil water potential is to use it effectively. Think of it as a type of plant thermometer that indicates “plant comfort”—just as a human thermometer indicates human comfort (and health). Here’s an analogy that explains the concept of soil water potential in terms of optimizing irrigation. 

Read more—>

Hydraulic Conductivity: How Many Measurements Do You Need?

Two researchers show easier methods conform to standards

If you’re measuring saturated hydraulic conductivity with a double ring infiltrometer, you’re lucky if you can get two tests done in a day. For most inspectors, researchers, and geotechs—that’s just not feasible. Historically, double ring methods were the standard, however the industry is now more accepting of faster single ring methods with the caveat that enough locations are tested. But how many locations are enough?

Triple the tests you run in a day

Drs. Andrea Welker and Kristin Sample-Lord, researchers at Villanova University, are changing the way infiltration measurements are captured while keeping the standards of measurement high. They ran many infiltration tests with three types of infiltrometers with a variety of sizes and soil types. In this 30-minute webinar, they’ll discuss what they found to be the acceptable statistical mean for a single rain garden. Plus, they’ll reveal the pros and cons of each infiltrometer type and which ones were the most practical to use. Learn:

  • What types of sites were tested
  • How the spot measurements compared with infiltration rates over the whole rain garden
  • Pros and cons of each infiltrometer and how they compared for practicality and ease of use
  • What is an acceptable number of measurements for an accurate assessment

Register now—>

Presenters

Dr. Andrea Welker, PE, F.ASCE, ENV SP, is a Professor of Civil and Environmental Engineering and the Associate Dean for Academic Affairs at Villanova University. She joined Villanova after obtaining her PhD at the University of Texas at Austin. Her research focuses on the geotechnical aspects of stormwater control measures (SCMs) and the effectiveness of SCMs at the site and watershed scale.

Dr. Kristin Sample-Lord, P.E., is an Assistant Professor of geotechnical and geoenvironmental engineering in the Civil and Environmental Engineering Department at Villanova University. She received her PhD and MS from Colorado State University. Her research includes measurement of flow and transport in soils, with specific focus on green infrastructure and hydraulic containment barriers.

Just Released—New Environmental Measurement Podcast

Check out a new podcast made by contributors to the EnvironmentalBiophysics.org blog. We Measure the World is a podcast produced by scientists, for scientists. Application expert Holly Lane and data guru, Brad Newbold interview scientists from all types of disciplines who measure anything and everything about the world to make it better—and more sustainable.

Holly Lane interviews scientists from all types of disciplines

Hang with us to learn a lot and laugh a lot. Explore interesting environmental research trends, how scientists are solving research issues, and what tools are helping them better understand measurements across the entire soil-plant-atmosphere continuum.

Listen now—>

Improve Your Plant Study: 3 Types of Environmental Data You May Be Missing

What data are you missing?

The environment plays a large role in any plant study. Ensuring you’re capturing weather and other environmental parameters in the best way allows you to draw better conclusions. To accurately assess plant stress tolerance, you must first characterize all environmental stressors. And you can’t do that if you’re only looking at above-ground weather data.

For example, drought studies are notoriously difficult to replicate and quantify. Knowing what kind of soil moisture data to capture can help you quantify drought, allowing you to accurately compare data from different years and sites.

Get better, more accurate conclusions

It’s important for your environmental data to accurately represent the environment of your site. That means not only capturing the right parameters but choosing the right tools to capture them. In this 30-minute webinar, application expert Holly Lane discusses how to improve your current data and what data you may not be collecting that will optimize and improve the quality of your plant study. Find out:

  • How to know if you’re asking the right questions
  • Are you using the right atmospheric measurements? And are you measuring weather in the right location?
  • Which type of soil moisture data is right for the goals of your research or variety trial
  • How to improve your drought study, why precipitation data is not enough, and why you don’t need to be a soil scientist to leverage soil data
  • How to use soil water potential
  • How accurate your equipment should be for good estimates
  • Key concepts to keep in mind when designing a plant study in the field
  • What ancillary data you should be collecting to achieve your goals

Register now—>

Presenter

Holly Lane has a BS in agricultural biotechnology from Washington State University and an MS in plant breeding from Texas A&M, where she focused on phenomics work in maize. She has a broad range of experience with both fundamental and applied research in agriculture and worked in both the public and private sectors on sustainability and science advocacy projects. Through the tri-societies, she advocated for agricultural research funding in DC. Currently, Holly is an application expert and inside sales consultant with METER Environment.

The researcher’s complete guide to NDVI and PRI

NDVI and PRI: theory, methods, and application

Modern technology makes it possible to sample spectral vegetation indices such as NDVI and PRI across a range of scales both in space and in time, from satellites sampling the entire earth’s surface to handheld small sensors that measure individual plants or even leaves.

Figure 1: NDVI is sensitive to the amount of vegetation cover that is present across the earth’s surface (source: low res map obtained from an earth orbiting satellite)

What are NDVI and PRI?

NDVI and PRI are both spectral vegetation indices derived from measurements of relatively narrow wavelengths of reflected light (10 to 50 nanometers) in the electromagnetic spectrum. This is useful for measuring various properties in plant canopies. NDVI stands for the Normalized Difference Vegetation Index and PRI stands for the Photochemical Reflectance Index.

image of SRS spectral reflectance sensor to measure NDVI and PRI | METER Environment
The METER SRS sensor measures both NDVI and PRI and works with ZENTRA Cloud for data visualization in near-real time.

There are many types of spectral vegetation indices, however, this article and the webinar below focus on the theory, methods and application of NDVI and PRI as they are two of the most commonly used (see webinar).

 

NDVI is especially useful for measuring plant canopy structural properties such as leaf area index, light interception and even biomass and growth, whereas PRI is more useful for getting at functional properties of plant canopies such as light use efficiency. Recent literature shows that PRI is also useful for measuring foliar pigments.

Understanding canopy radiation interactions 

To understand where NDVI and PRI come from, it’s important to learn about canopy-radiation interactions. There are three primary fates for electromagnetic radiation as it interacts with plant canopies.

Read more—>

Evapotranspiration: Pitfalls to Avoid and Why It’s Easier Than You Think

Mistakes that kill your estimates

Measuring evapotranspiration (ET) to understand water loss from a native or a managed ecosystem is easier than it looks, but you have to know what you’re doing.

Learn causes and implications of uncertainty

If you can’t spend the time or money on a full eddy-covariance system, you’ll have to be satisfied with making some assumptions using equations such as Penman-Monteith.

Like any model, the accuracy of the output depends on the quality of the inputs, but do you know what measurements are critical for success? Plus, as your instrumentation gets more inaccurate, the errors get larger. If you’re not careful, you can end up with no idea what’s happening to the water in your system.

Get the right number every time

You don’t have to be a meteorologist or need incredibly expensive equipment to measure ET effectively. In this 30-minute webinar, Campbell Scientific application scientist Dr. Dirk Baker and METER research scientist Dr. Colin Campbell team up to explain:

  • The fundamentals of energy balance modeling to get ET
  • Assumptions that can simplify sensor requirements
  • What you must measure to get adequate ET estimates
  • Assumptions and common pitfalls
  • How accurate your equipment should be for good estimates
  • Causes and implications of uncertainty

WATCH IT NOW—>

Why is METER co-sponsoring an educational series with Campbell Scientific? Read the story

Presenters

Dr. Dirk V. Baker has been with Campbell Scientific since 2011 and is an Application Research Scientist in the Environmental Group. Areas of interest include ecology, agriculture, and meteorology—among others. He has a bachelor’s degree in wildlife biology and a doctorate in weed science, both from Colorado State University. Dirk’s graduate and postdoctoral research centered around measuring and modeling wind-driven plant dispersal.

Dr. Colin Campbell has been a research scientist at METER for 20 years following his Ph.D. at Texas A&M University in Soil Physics. He is currently serving as Vice President of METER Environment. He is also adjunct faculty with the Dept. of Crop and Soil Sciences at Washington State University where he co-teaches Environmental Biophysics, a class he took over from his father, Gaylon, nearly 20 years ago. Dr. Campbell’s early research focused on field-scale measurements of CO2 and water vapor flux but has shifted toward moisture and heat flow instrumentation for the soil-plant-atmosphere continuum.

Learn more

Download the “Complete guide to irrigation management”—>

Soil Moisture Sensors Aid Crop Production in Space

If you’re an astronaut on an exploration Mission to Mars, lack of breathable oxygen isn’t the only challenge you’re facing. There’s another issue that can heavily impact your performance: lack of veggies.

Mars

It turns out the astronaut food system must be supplemented with fresh crops during long-term exploration missions. NASA has identified that vitamins and antioxidants degrade over time and is now funding research on the best way to grow fresh vegetables in space to supplement astronaut nutrition.

How well do plants grow in space?

Researchers including Dr. Oscar Monje, research scientist at NASA’s Kennedy Space Center in Florida, are studying the best materials and methods for growing vegetables in space. Monje says, “Growing plants in a space station is challenging because both space and power are limited. All the plant chambers built in the past 40 years focused on enabling space biology studies that centered on how to grow plants in space. They wanted to know the effects of growing in zero gravity. Can plants grow normally? Are they stressed? Can they produce seeds? But now we want to focus on space crop production. We want to supplement astronauts’ diets with essential minerals and vitamins during long duration missions.”

Kennedy Space Center

Early growing experiments in the BPS

Monje was a student of Dr. Bruce Bugbee at Utah State University who studies plants in space for bioregenerative life support systems. After graduating and doing a postdoc at the Space Dynamics lab, he started at Kennedy in 1998 researching how to grow wheat in space in the PESTO (Photosynthesis Experiment and System Testing Operations) Experiment. Dr. Gary Stutte, the principal investigator and Dr. Monje grew wheat in the Biomass Production System (BPS), a four chamber system that consumed 280 W of power. The BPS was used to measure photosynthesis, demonstrating plant harvests, priming pre-planted root modules, pollinating plants, as well as collecting gas and liquid samples.

Monje says, “Back then, all experiments were shuttle experiments (7-11 days at a time). The PESTO Experiment flew for 73 days in space and was essentially several shuttle missions conducted back to back. We measured root zone moisture with a pressure sensor monitoring root module matric potential. We learned that as long as you provide plants with adequate root zone aeration, good soil moisture, and the right light and CO2, they grow normally with no visible plant stress—just like on earth. The BPS was a precursor of the Advanced Plant Habitat (APH) facility on the International Space Station plant, an environmentally controlled growth chamber designed for conducting both fundamental and applied plant research for experiments lasting as long as 135 days.

New growth chambers introduced

The BPS was very complex, but the chambers were small and the light level was moderate. Ten years ago, NASA developed two large area (0.2 square meter) crop production systems to grow fresh salad crops in substrate-based media for the astronauts: the “Veggie” and the “APH”. Monje says, “Veggie is open to the cabin so there is no environmental control of CO2 or temperature, and it is watered by the crew. The light level provided by red, blue and green LEDs is moderate and the environment is not monitored. However, it grows lettuce crops that are safe to eat by the crew. The Advanced Plant Habitat on the other hand, is a Cadillac compared to the Veggie. With the APH you can load experiment profiles from the ground that control the light level (up to 1000 umol/m2s, half-full sunlight), the spectral quality, the CO2 concentration (up to 5000 ppm), photoperiod of light, and root zone moisture. The APH can be monitored in near-real time with minimal crew intervention for weeks at a time. To date, it has been used to grow wheat, Arabidopsis, and radish crops during space biology and crop production experiments”

The APH has been used to grow wheat, Arobidopsis, and radish crops

Measuring root zone moisture in space

Monje says that the 5-cm tall APH root zone is divided into four independently controlled root modules, called quadrants. In each quadrant, media moisture is controlled based on matric potential using a pressure sensor. However, the matric potential measured by the pressure sensor does not capture vertical variation in volumetric moisture. He says, “Each quadrant is watered with a porous tube system that distributes water throughout the porous media (arcillite) that is mixed with slow release fertilizer. In the 5-cm tall root zone at one g, most of the water is ponded at the bottom, and the top layer of media where the plants are germinating can become too dry. For these reasons, two small, rugged volumetric EC-5 moisture sensors were added to each quadrant to monitor moisture redistribution phenomena in microgravity. These sensors are insensitive to salinity and temperature effects. Thus, APH uses eight volumetric moisture sensors, two in each quadrant (one high, one low) to monitor root zone moisture. When watering in space, moisture redistribution occurs because capillary forces in microgravity distribute water evenly across the substrate and affect aeration. Even though the sensors are at different heights, they can read the same, as opposed to one flooded and the other one drier.”

Monje adds that, “Balancing the mix of aeration with enough water in a microgravity environment is the crux of the problem. If you don’t water plants enough, they don’t grow fast enough, but if you give them too much water, then you inhibit O2  supply to roots and nutrient uptake. So we’re using volumetric water content sensors in the APH root module at different levels to control the moisture. The sensors are like our ‘fingers in the soil’.”

What’s next?

Monje says the next step is to develop novel watering systems that do not use granular media.  He says, “Each APH root module holds about six kilograms of arcillite media, which is used only once per crop. Similarly, Veggie uses nearly two kilograms of media distributed into six independently watered root modules. Although these root modules grow normal plants in space biology experiments, this approach is not sustainable for crop production as transporting this much mass all the way to Mars is not going to be feasible.”

Deploying experiments on the moon can be challenging

Monje believes that getting these crop growth systems ready for a trip to Mars may take a while. He says right now, the Moon is a new proving ground for these technologies as part of the Artemis program, and deploying experiments on the Moon brings new challenges too. He adds, “An interesting thing about the Moon is you have partial gravity. It’s not one g. It’s 1/6 g. Plus, you have the issue of space radiation, and temperature must be controlled, unless you deploy your experiment in a manned habitat. From a biology point of view, we want to understand how plants will respond to growing in high radiation and partial gravity environments.”

Monje says it’s been an incredible journey to work on this type of research for many years. He laughs, “Since 1998, I’ve been pinching myself every day because this work is so challenging and yet so much fun. It’s pretty amazing.”

Learn more about measuring soil moisture

Download the Researcher’s Complete Guide to Soil Moisture—>

Smart orchard aims to install thousands of sensors for actionable insights

When big data is a problem

Orchard growers today live in an exciting time where environmental data are becoming inexpensive and abundant. But going from a data-poor to a data-rich environment has its challenges. Big data can be so overwhelming that growers struggle with how to turn that data into actionable insight.

In March, Innov8.ag began piloting a smart orchard project in collaboration with researchers from Washington State University & Oregon State University at Chiawana Orchards in Washington state.

One grower on the Washington Tree Fruit Research Commission recently commented that he uses no less than 19 data apps for making decisions. Steve Mantle, founder of innov8.ag, says, “It’s just overwhelming to a grower to consolidate all of this data together. We need to figure out how to help them with actual insights that impact either their yield quality / quantity—and just as importantly—their costs: particularly on labor, chemical/nutrients, and irrigation.”  That’s why in 2020, Mantle and his team approached the Tree Fruit Research Commission’s technology committee to see if they could bring their capabilities, ingesting data from many different data silos and sensor providers into one place, with the goal of providing actionable insights for growers in the apple orchard space. Thus, the idea of a “smart orchard” was born.

Turning big data into a solution

In March, Innov8.ag began piloting a smart orchard project in collaboration with researchers from Washington State University & Oregon State University at Chiawana Orchards in Washington state. Their goal was to “sensorize” an orchard from multiple hardware providers, bringing together growers, data, and researchers to create a sustainable, “smart” orchard with insights that impacted a grower’s bottom line. To do this they combined data from on-farm and off-farm, online and offline sources including satellites, drones, weather providers, telemetry from IoT devices such as soil moisture probes and leaf wetness sensors, and more.” Mantle adds, “We’re trying to see how the sensors at different price points and from different vendors compare against each other in terms of accuracy. But the biggest goal is to get more granularity around and prove the value in canopy, soil, and weather measurements. Then we tie that in with yield, quality, and profit.”

Installing sensors so that comparisons are valid

The smart orchard consists of 100 rows of Gala apple trees spaced out over two 20-acre blocks. A number of different sensor/instrumentation providers, including METER Group, have their sensors deployed at this smart orchard measuring parameters such as weather, irrigation, soil water and nutrients, chemicals, disease, pests, crop health, labor, and drone/satellite imagery. All these data are aggregated and organized on a regular basis to try and enable growers to better understand weather and climate change to make precise, informed decisions and better manage their water usage, labor, equipment, and chemical usage.

Smart Orchard team member and researcher, Harmony Liu, says one challenge they face is making sure the comparisons are valid. “We are careful to install the same sensor types at the same heights so we are making “apple-to-apple” comparisons.”

Liu says in addition to sensing, they collect soil samples every week throughout the season and send them out to two different labs for nutrient testing so they can look at how that data compares with the soil nutrient sensors. They sample at five different locations at three different depths to match the sensors. She adds, “We have the dendrometer, soil nutrient data, soil moisture data, and canopy data all being collected within the same zone. It’s part of our intent to show this data all connecting with each other.” The team also measures irrigation line pressure with a sensor as opposed to using an irrigation switch. Liu says, “We want to know what the pressure signature is as everything turns on and activates so we can understand what that signature looks like and start to identify when there are abnormalities in how the irrigation system fills.” Additionally, they’re using METER NDVI and PRI sensors as well as a pyranometer for ground truthing the drone imagery that they’re doing at a 7 centimeters per pixel resolution.

The goal is understanding in-canopy weather and how to work with institutions on adapting models for disease, pests, and ultimately informing spray management.

Data cleanup is time-consuming

Liu says getting the smart orchard up and running was not without its challenges. “The first challenge was gaining access to some of the data from grower owned instruments because those instruments are not all grouped together.” Liu says that challenge made data cleanup time consuming, but they worked their way through it. She adds, “Overall, having this density of data is difficult because it’s a lot to wade through. But at the same time, it’s been really helpful. Data has been reliable coming in across the board.”

In-farm vs. outside-farm measurements

Liu says one thing they are interested in is accurately measuring temperature and humidity within the orchard because these parameters are critical for apple disease modeling. She says, “When people are modeling disease, they take the inputs from weather forecasts into the disease model for risk calculations. But there are some differences in environmental conditions inside vs. outside the orchard where evapotranspiration will cause temperatures in the canopy to be cooler compared to outside-farm temperatures while the vapor pressure is higher. So that’s one thing we use METER group instruments for. We have outside-orchard,  above-orchard, and in-canopy ATMOS 41 weather stations and ATMOS 14 temperature and relative humidity sensors. We use these to compare the temperature and relative humidity difference. By using an instrument from the same provider, we eliminate the systematic bias vs. if we were to compare temp and RH from different providers. We also set up a vertical profile by installing sensors on the same pole at different heights and could see how the temperature and humidity changed across height for that location.”

Register for the smart orchard project live webinar with innov8.ag this Thursday, Jan.14th at 4pm PST.

Future smart orchard goals

Mantle says their most important goal is understanding in-canopy weather and how they can work with WSU and other institutions on adapting models for disease, pests, and ultimately informing spray management. Liu adds, “We also want to understand data comparison and unification. We want to bring together soil moisture measurements like volumetric water content and data from the METER TEROS 21 matric potential sensor. What we found is that, although they’re looking at soil moisture from different perspectives, unifying the two measurements will be critical for people working on irrigation scheduling.” The team also plans on working with WSU professors to create an evapotranspiration map that blends together some of the sensor telemetry and the view from a drone.

See the webinar

Want to learn more? METER soil physicist, Dr. Colin Campbell and Washington State University soil scientist Dr. Dave Brown discuss the smart orchard project in a METER Group webinar.

View more METER crops webinars—>

Learn more

Download the “Complete guide to irrigation management”—>