Walt Mahaffee, Plant Pathologist



Behind us is an eddy covariance tower.

Eh, actually it's more of a souped-up eddy covariance tower

because we have six sonics on it instead of the usual one.

But what this tower does is it actually

looks at the turbulent airflow, surface energy, and carbon

and vapor flux.

Tara Heel, my lab manager and right-hand person in the lab,

she's over on that eddy covariance tower right now

doing some general maintenance.

One of the reasons that we understand air turbulence

is to understand pathogen movement and dispersion.

Walt Mahaffee

I'm Walt Mahaffee, I'm employed by the United States Department

of Agriculture, the Agricultural Research Service,

and based at the Horticultural Crops Research Lab

in Corvallis, Oregon.

I also work with the Oregon Wine Research Institute

and the researchers there.

We're here at Stoller Family Winery.

And we do a lot of research here with Jason Tosch, the vineyard


And we're looking at direct sunlight, scattered

light, short, long-wave.

We're also looking at the three-dimensional aspects

of air turbulence.

We have probably 30 different types of thermal couples

on there looking at fine responses in air temperature,

there's infrared sensors looking at surface energy

or radiative heat transfer, leaf wetness, soil moisture.

All of this is being recorded at about 20 Hertz--

or about 20 times its second--

in order to understand that fine detail

that comes about when you look and see leaf flutter

and dust movement.

You think about powdery mildew spores, they're--

well, let's use an analogy.

Think of the Goodyear Blimp.

Goodyear Blimp

A Goodyear Blimp is about the size of a powdery mildew spore

if a grape leaf is the size of the Willamette Valley.

You can imagine there's a wild number of microclimates

within the Willamette Valley that that Goodyear Blimp can

land in and experience very different temperatures,

moisture regimes.

All of this goes into understanding

how canopy architecture influences air turbulence,

and in turn, how that affects disease spread.

Micro meteorology stations

We also have some experiments that

are starting up here on using micrometeorology stations.

A LEM is a low energy meteorological station.

This was developed by Nipun Gunawardena and Eric Pardyjak

at the University of Utah.

We have sonic that does air speed wind,

we have solar radiation temperature, surface energy

or surface temperature, as well as

soil moisture all wrapped up into this weather station,

for a little over 1,000 bucks.

Most of us are familiar with Weather.com or Weather

Underground or your local weather

that you get off TV or radio.

That is all what we call downscaled to four kilometers.

So these limbs are helping us understand

how terrain influences microclimate formation, how

canopy architecture influences that so that we can give you

that type of estimate down to a, say, 80-meter grid cell.

Eventually, we hope to have that down to a planet.

The reason this is important is because in vineyards, you

want to stay away from cold pockets for frost damage,

or you want to predict where that best microclimate is

for your reserve Pinot Noir.

And we can give you an idea even before planting

where these microclimates are going to form.

All the data that we're collecting in here

actually goes into two different projects, one

that we call Ag Risk, and the other one is--

a lot of people say "A Pie in the Sky" project--

that is, building a vineyard simulation environment.

They're both synergistic projects and that one feeds off

of the other.

What we're trying to do with Ag Risk

is actually create a modeling environment that

takes in all the risk that you're

trying to manage in an agricultural setting.

It's not going to give you a decision,

it's giving you a better, more complete information

and the uncertainty around the predictions

so that you make better decisions.

Fungicide resistance is one of the practical components

of all this modeling work.

We've in the last few years discovered QoI or Strobilurin

resistance within grape powdery mildew.

We've developed a rapid molecular tool

to detect where resistance isolates are.

But now the grower has a question

is, well, you can tell me that I have a resistance isolate,

but where is it?

With the turbulence airflow modeling,

we can give you an estimate of what area of your vineyard

is at risk.

We can also look at the larger region

and tell growers as the season progresses

where is the risk for this fungicide resistant isolate

to be.

When they have that two-day window to get the tractors out,

they know where to target with that two-day window

for their fungicide applications.

Sim City

If you look at this computer software

package called Sim City, it's a computer game

that a lot of kids play.

Trainers of urban planners are actually using this.

Sim City has zero predictivity to an urban environment

for a real urban manager, but what it does

is it teaches them to make better decisions

with limited data sets.

And they can play around with some crazy ideas.

Think of a vineyard manager that's

wanting to try some really new things that they can

go into the simulation environment,

they can try some ideas that they normally

wait because it's just too expensive to try the idea out

in the real world.

What we envision being the delivery mechanism for growers

is, well, Google Glass.

If you can imagine yourself jumping on your pickup truck

and you're looking and everywhere you look,

you see the data that you need.

We can see ground-based robots carrying sensor packages

around, drones flying overhead.

So where we see this going, it might be 30 years.

I might be dead and buried by the time it gets there.

But again, the way technology is moving,

it could be five or even 10 years that we actually

have this type of environment.


Walt Mahaffee is a research plant pathologist with the USDA Horticultural Crop Research Unit in Corvallis and a courtesy faculty member of the OSU department of botany and plant pathology. He is a core researcher with the Oregon Wine Research Institute. He is at work on a risk-management system for agricultural crops that includes a robust simulation environment and autonomous robots equipped to make fine-scale management decisions. Special Thanks to: Bill Boggess, Executive Associate Dean, OSU College of Agricultural Sciences Danielle Gabriel, inspiration for OWRI research video series.

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