All posts by scherrm
Meet the Team: WINTER UPDATE
At the Western Region International Plant Propagators Society (IPPS), the Pacific Northwest Insect Management Conference (PNWIMC), and the Orchard Pest and Disease Management Conference (OPDMC) last month, we presented cutting-edge research and advancements in our field. Our presentations at the Western Region IPPS and PNWIMC focused on the latest developments in sensor-controlled irrigation, and flatheaded borer management, respectively.
At the Orchard Pest and Disease Management Conference, we discussed the latest techniques in IPM for managing powdery mildew with biological fungicides applied by our laser-guided Intelligent Sprayer system. Through our presentations at these conferences, we aim to advance the knowledge and understanding of plant health in our field and to promote collaboration among professionals. By sharing our research and engaging in discussions with our peers, we strive to advance the science of horticultural production to support the growth and success of the horticulture in the Pacific Northwest region.
At NWREC, we have been working on our new hydroponic greenhouse project. However, since October we have encountered construction challenges in connecting the natural gas heaters, which has impacted the growth of crops such as lettuce, tomatoes, and cucumbers. As a result, lettuce growth has been slow and plagued by Botrytis, and warmer-growing crops like tomatoes and cucumbers have fared even worse. We are working to resolve the permitting issues with the heaters as soon as possible and look forward to updating you on the progress of the greenhouse project in the coming year.
Meet the Team: Unmanned Aerial Systems
Unmanned Aerial Systems applications in agriculture have interested me from the time I saw some trial flights at the World Ag Expo in Tulare, California in 2020. The possibilities of crop mapping, using multispectral imagery to create NDVI data, and optimizing resources seemed
endless. And while all of this is still true, I have learned over the last couple years that there is a lot more to it than just getting out the drone and flying it over a field.
In the Fall quarter of 2022, I was able to take a class on campus from Dr. Michael Wing called “Unmanned Aerial Systems Remote Sensing. In this course I was able to get some hands-on experience flying a DJI Phantom 4, a DJI Matrice 200, and a DJI Matrice 300. We also were able to take aerial imagery with a MicaSense Altum multispectral and thermal camera attached to the DJI Matrice 300 and analyze that data during the course of the class. To analyze the data we learned how to use AgiSoft Metashape photogrammetry software to make orthomosaics of our area of interest. With the orthomosaics, we were able to perform different sorts of analysis using ArcGIS Pro software and R. This class really gave me a solid introduction to the collection and analysis of aerial imagery.
With some knowledge under my belt after taking that course, I decided to look into taking the Part 107 Certification exam to obtain my FAA administered Remote Pilot License. The purpose of this certification is to be able to fly a drone for commercial, government, or any other non-
recreational purposes. In the Nackley Lab, we have access to a DJI Matrice 210 quadcopter and a MicaSense Red-Edge M camera so I wanted to be able to open up some more avenues for research by being able to pilot this drone for our lab!
In our lab, a lot of our work centers around major challenges to the nursery production industry in Oregon. Working with a drone can allow you to survey a large area for early signs of drought stress, nutrient deficiencies, or pests to minimize a loss in yield. Now that I have the Remote Pilot Certification, my goal is to help our lab create more aerial imagery (data) that ties into our work which addresses major challenges to nursery production in Oregon like irrigation application, pest management, plant nutrition, and climate adaptations.
Thinking about getting a Remote Pilot Certification? Here are Sadie’s tips for Studying (click here).
For more information about the part 107 certification or UAS applications feel free to contact me
Other great OSU resources:
BEAV UAS Program – Dr. Kristine Bucklin and Dr. Lloyd Nackley
Aerial Information Systems Laboratory – Dr. Michael Wing
Plant Health: Sensor-controlled sprayers for specialty crop production
Recently our own Brent Warneke wrote another great article for Sprayers 101 covering the Intelligent Sprayer System – check it out here: https://sprayers101.com/airblast-sensors/
Want a preview? Here’s a synopsis:
Air-blast sprayers are versatile, reliable, and can be modified to fit numerous types of crops, all of which are reasons for their continued popularity. Yet despite their popularity, air-blast sprayers have long had a reputation for inefficient application characteristics. Sensor controlled spray systems reduce labor costs and pesticide waste. Recently, they are receiving renewed interest as their reliability has improved and more options have become available. There are two main types of sensor sprayers:
+ On/off sensor sprayers
+ Crop adapting sprayers
Infrared sensors: The inability to resolve characteristics of plant structure makes IR sensors suited to less complex applications such as triggering
the sprayer on and off at a plant. Additionally, these systems can be used for herbicide sprayers where the sensors are aimed at the trunks of trees/vines and turn off the sprayer as they pass the trunk or to target it for the purpose of sucker sprays.
Ultrasonic sensors: using multiple sensors, it’s possible to collect canopy volume data with similar accuracy to taking manual measurements. These are typically used on canopy sprayers with around 3 sensors per side of the sprayer.
Laser sensors (LiDAR): Provides the most accurate measurements of plant structure (mm resolution). Only one sensor needed for accurate measurement.
Plant fluorescence sensors: These have a spatial resolution between ultrasonic sensors and LiDAR sensors. Most commonly used on “weed-seeing” herbicide sprayers but also on canopy sprayers. All sensor sprayers must have a speed sensor to synch the sprayer ground speed to the sensor system.
Spraying with sensor sprayers
Insect pest and disease control with sensor controlled sprayers has
been widely shown to be similar to that of standard sprayers. Control can be achieved on those crops with spray volume savings from 20-70% depending on the sensor system used and crop spray volume savings are higher in crops with more variability labor savings, less pesticide release into the environment, tractor wear, and driver fatigue are also reduced as the sprayer is in operation for less time.
Sensor sprayers can result in 20% to over 90% less spray drift. Autonomous sensor sprayers companies are currently developing and selling autonomous sprayer units that drive themselves and can be integrated with sensors.
Meet the Team: The Bounty of a Season
Success in Summer 2022
For the past few years we’ve limited gatherings on the farm due to COVID-19 restrictions. In the summer of 2022, however, we were finally able to welcome the public back for Nursery Program Field Days. We’d like to take this opportunity to boast about a few of our highlights from the last several months.
For the first time, the Nackley Nursery Production team was an official stop on the Oregon Association of Nurseries Farwest Innovative Production Grower Tour. Our portion of the tour at NWREC showcased sensor-controlled irrigation, heat-stress mitigation techniques, LiDAR smart-sprayer systems, and practices that can reduce boxwood blight spread, and methods of scouting and monitoring insects in nurseries and greenhouses. These projects offer a wide range of savings for growers.: up to 80% improvement in irrigation efficiency, up to 70% reduction in sprayed pesticides, and a significant reduction in boxwood blight infection.
The second big event was an open house for our Climate Ready Landscape Plant trial, the largest coordinated landscape plant irrigation trial in the Western US. Plant professionals from around the region came to rate plants and discuss how we, as a society, are going to maintain healthy landscapes while faced with increasing extreme weather.
Ongoing projects that will continue this year include, research by our graduate student Sadie Keller, who is investigating Oak and Maple drought tolerance. This summer, Sadie shared her preliminary findings with scientists at the American Society for Horticultural Science, in Chicago.
In addition, Dr. Melissa Scherr continues our research on the Pacific Flatheaded beetle, with the anticipation of a grower event hosted at NWREC discussing current research on Flathead Borer biology and control this coming April – 2023.
Meet the Team: From Hiking to Horticulture
I am originally from the great city of Tacoma, Washington. I went to an outdoors based high school where my love for plants and environmentalism blossomed. My favorite class was our version of “PE”, where we hiked through Point Defiance Park identifying native species. This passion drove me to pursue a bachelor’s degree in Environmental Science at the University of Redlands. Moving to Redlands in Southern California was a stark contrast to my home in Puget Sound, but I grew to love most parts of it!
I went on many abroad terms and saw amazing parts of the world such as Peru, Ethiopia, and Iceland. Each time I returned I wished I had been there longer and itched to immerse myself even more in a different country. Once I graduated from Redlands, the natural next step was to join the Peace Corps. I spent two years in the Southeast corner of Senegal, West Africa. I lived in a 100-person village in the region of Kedougou where I learned to speak Jaxanke. As an Agroforestry Extension Agent, I helped with various agriculture and agroforestry projects. We created small-scale nurseries, collected seeds, showcased new and improved agroforestry techniques, and outplanted trees and shrubs around the village. I loved my time in Senegal and miss being there constantly.
After returning to the United States, I moved to Eugene, OR to work at Dorena Genetic Resource Center. I assisted the lead horticulturist in end-to-end native plant restoration, collecting/processing seed, and producing native plants to restore areas affected by fires, floods, and construction. I became the lead irrigator, which was a new problem-solving and damp adventure, and led seed collection trips across Oregon. I also helped develop a seed collection mapping application to track plant populations and store seed collection data.
This leads me to OSU! I just started at OSU this fall to pursue my Masters in Horticulture and work in the Nackley Lab. I am partnered with Sadie Keller on a project looking at stem hydraulics and how it relates to drought in shade trees. I am new to this type of research but am so eager to learn more! I am excited to get our stem hydraulics lab up and running and start the journey of data collection.
Climate-Ready Landscape Plant FIELD DAY
Who should attend: Professionals from landscape, horticulture, nursery and related fields; OSU Master Gardeners; garden writers; academics/educators
When: September 14th 2022; 10am – 2pm (Arrive when convenient; ratings take about 60 min)
Where: OSU’s North Willamette Research & Extension Center
15210 NE Miley Rd, Aurora, OR 97002
What’s involved: Evaluating aesthetic qualities of selected landscape plants (about 60 minutes).
About this Event
The ever-changing climate iputs pressure on the industry to develop more sustainable plants. As part of a six-university study, OSU seeks to improve urban water-use efficiency by evaluating landscape plant performance on three irrigation treatments corresponding to the Water Use Classification of Landscape Species (WUCOLS): High, Moderate, and Low categories of water need. The plants are irrigated regularly during their first summer after planting. Treatments are imposed during the second growing season where researchers collect growth and quality ratings.
The Field Day allows landscape, nursery, and horticultural industry professionals and educators the opportunity to see new plants in their 2nd year and share your opinions and preferences by rating a representative sample of the plants in the field undergoing irrigation treatments. One plant from each of the 3 water levels, for 15 different species (some released to the public and some not yet) will be surveyed. Along with this field of 360 plants, you will be able to get a sneak peek at the next year’s field, currently in an establishment phase.
Important Details: The fields are packed dirt/uneven mulch, sturdy comfortable shoes, sunscreen and/or a hat are suggested. At the trial site, you will be provided a ratings sheet, clipboard, pen, and given general instructions when you arrive. It is a self-guided tour among our 720 landscape plants. Lots to look at but only a small sub set to evaluate. Hot Coffee and cold water will be provided. We value your feedback and hope to see you there!
For questions contact:
2022 Field Day Tour and Open House
August 23, 2022
Nackley Lab nursery production open house takes place August 23. 2023 from 11am – 2pm
Our event will be a part of the great Nursery related activities happening around the Willamette Valley as part of the Oregon Association of Nurseries Farwest Show, which will also feature Dr. Nackley, and Brian Hill, M.S. and many others from Oregon State and beyond.
The Nackley lab open house will feature research on our four themes: Irrigation science, pest management, plant health, and plant trials.
Free to all, no registration required.
Parking: follow signs to south side of the Cravo North Willamette Research and Extension Center and then follow signs walk 5 mins (west) to Nackley Lab Welcome Center.
Masks are welcome, not required, per University policy
The tour route will travel through fields with uneven terrain. Farm cart transport (e.g. gators) can be available for those who request assistance.
Schedule of Events
11 :00 -11:15 Station 1. Welcome, overview of the program and biostimulant research on Shade-Trees
11:15 – 11:30 Station 2. Plant-based irrigation scheduling: pressure bomb and infra-red thermography
11:30 – 11:45 Station 3. ET-based irrigation scheduling and Flatheaded borer research
11:45 – 12:00 Station 4. Cover cropping and Heat-stress prevention
12:00 – 12:15 Station 5. Boxwood blight control
12:15 – 12:30 Station 6. LiDAR “smart” air-blast sprayer and drone demonstration
12:30 – 1:00 Station 1. Open chat with research team, refreshments and grilled sides.
1:00 – 2:00 Self guided tour. Researchers will be at each of the six stations to answer questions. Sprayer demos will take place at station 6 every 15 mins.
People: Oregon bound and down; From the land of sun to the land of clouds
I grew up in Littleton, Colorado amid the suburbs of Denver. Although I was a suburb kid, I grew up gardening from an early age, which sparked my love for plants. Going with what I was interested in, I decided to pursue a degree in something plant related at Colorado State University. I ended up studying horticulture, but took a wide range of classes including brewing technology, microbiology, biochemistry and business. Throughout my time at CSU I worked in a couple different lab groups, one that studied biofuel production and another that was focused on cryopreservation of vegetatively propagated crops. Working in the labs got me interested in science. I took a plant pathology course my senior year and loved how it was an integration of things I had learned in horticulture, microbiology, and other sciences.
Eventually I obtained my BS in Horticultural Science and a minor in Business Administration at CSU. I had such a good time learning about science and working in labs that I decided to pursue graduate school. I looked at a few universities throughout the USA but the prospect of working on specialty crops (fruits and nuts) had me more excited than working on field crops. I ended up landing at Oregon State University in the Botany and Plant Pathology Department. The project I worked on had me investigating fungicide resistance and grape powdery mildew management and I was fortunate to travel to many vineyards throughout the state to take samples and work with growers. Over the course of my Master’s degree I was able to present data from my research at two national plant pathology conferences, one in Tampa, FL and the other in San Antonio, TX, two places I had never been before. These experiences were very useful to hone my science communication skills which I use a lot in my current position.
After I finished my MS degree I started my current position working on the Intelligent Sprayer project at OSU with Drs. Lloyd Nackley and Jay Pscheidt. The part of the project I fit into investigates using the Intelligent Sprayer to manage grape powdery mildew with various fungicide regimes and investigating sprayer coverage in hazelnut and nursery crops. This has been a great fit for me as I have been able to apply what I learned during my MS and strengthen my research and writing skills. As with all agriculture, we come up with a plan every year and have ideas about how everything will go, but something always surprises us. During the season it’s always a push to collect all the data we need, but when the season is over it is very interesting to sit down, go through the data, and make graphs and connections as to how the treatments we applied fared. Writing up the data into informative reports, and in doing so, making connections to past literature while abstracting it into the future is another part of the process that makes me love what I do.
I’ve been fortunate to live in two different states that are great for my outdoor oriented lifestyle. I grew up camping, fishing, backpacking, canoeing and skiing in Colorado. I have since gotten into rock climbing, rafting and kayaking, and hunting in Oregon, and especially love spending time on the Oregon coast. If I were to give some advice to someone following a similar career path to me I would tell them to always be open to opportunities and to get out of their comfort zone regularly.
Irrigation: Drought Physiology of Ornamental Shade Trees
- Shade tree growers need to be prepared for the effects of climate change in Oregon.
- In order to equip growers with the tools necessary for production success, we aim to determine critical shade tree stress thresholds, characterize plant responses to drought conditions, and correlate remotely collected spectral images with ground based plant water stress measurements.
- Previous studies have sought drought response measurements for Acer rubrum (Red Maple) and Quercus rubra (Red Oak), but never in a nursery production setting.
- We aim to disseminate this information to Oregon shade tree growers at the completion of this experiment with the hope to aid growers in making data driven irrigation decisions and demonstrate the use of these technologies in nursery production settings.
In Oregon’s Willamette Valley, the heart of the nursery country, rainfall is scarce during the summer and humidity is low. Oregon’s dry summer conditions can lead to low moisture stress conditions for maples and oaks in normal years. Plant stress resulting from low soil moisture, high heat, and low relative humidity have been exacerbated in recent years with the increasing frequency of heatwaves and drought. Drought and heat stress scorch the maple and oak canopies, which can lead to decreased plant quality and economic losses for shade tree growers. Sensor-based technologies can be used to model plant responses to environmental gradients to develop warning systems to help growers prevent stress and bridge a knowledge gap in the nursery production industry regarding drought responses.
How are we studying plant stress responses?
Starting late June 2022, we will implement two irrigation treatments (well-watered and drought) in our shade tree planting with each row having independent irrigation control. The well-watered rows will be maintained at a soil water potential of >-1.0 mPa. The drought treatment rows will be allowed to naturally dry down to a soil water potential of -4 mPa. If during the experiment, our metrics (stomatal conductance and stem water potential) do not show considerable responses at -4 mPa tension, we will allow the drought treatment to continue to dry down progressively (-1 mPa) until stress is evident.
Why and how do we measure stem water potential?
Plant water status is commonly defined in terms of water potential or the ability of the water to do work. In most cases, well watered plants have “high” water status and drought conditions lead to a “low” water status (Levin and Nackley 2021). Using the pressure chamber, we will take midday stem water potential measurements twice weekly from 12pm-3pm. This time frame is important because it represents the time of day where leaf transpiration is at its maximum.
First, we will cover the leaf and stems to be measured with an opaque bag for at least 10 minutes before pressurization to allow the plant to stop transpiring. Once we excise the sample from the tree it should be placed into the pressure chamber or “pressure bomb” within 30 seconds (Levin 2019). Once the stem is placed into the chamber and pressure is applied, the amount of pressure that it takes to cause water to appear at the cut surface tells us how much tension the stem is experiencing.
Why and how do we measure stomatal conductance?
We measure stomatal conductance using a porometer that measures the degree of stomatal openness and the number of stomata (Licor.com). This indicates the plant’s physiological response to its current environment. If a plant is stressed, it will tend to close its stomata and lower the stomatal conductance rate. We will be using a combination of the LI-6800 Portable Photosynthesis System and the LI-600 Porometer/Fluorometer to make our measurements twice a week from 12pm-3pm.
For more information:
Please stay tuned in the coming months for more blog posts about how we will find plant stress thresholds by measuring the hydraulic conductivity of these shade trees. We will also correlate remotely collected spectral and thermal images with our ground based plant stress measurements to demonstrate how implementing a UAS equipped with a multispectral and thermal camera can be used to detect water stress in nursery production.