July 7, 2025 • 34 mins
Sarah and Luis discuss armyworms as a significant pest in California rice production. The discussion included Luis providing current updates on armyworm populations, scouting techniques, treatment thresholds, and management options for rice farmers.
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Armyworm Resources
Second Peak of Armyworm Podcast Episode
Other Resources
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Transcript
Episode Transcript
Available transcripts are automatically generated. Complete accuracy is not guaranteed.
SPEAKER_02 (00:00):
Hello and welcome to Thoughts on Rice, a podcast
hosted by the University ofCalifornia Cooperative Extension
Rice Advisors.
I'm one of your hosts, SarahMarchionish, and I'm a rice farm
(00:21):
advisor for Colusa and Yolocounties.
SPEAKER_00 (00:25):
I'm Whitney from DeForest.
I'm the Cooperative ExtensionRice Advisor for Sutter, Yuba,
Placer, and Sacramento counties.
SPEAKER_03 (00:32):
My name is Luis Espino.
I'm the Rice Farming SystemsAdvisor for Butte
SPEAKER_01 (00:38):
and Glynn counties.
I'm Michelle Leinfelder-Miles.
I'm a Farm Advisor in the Deltaregion.
I work on all sorts of fieldcrops, grains and forages.
but one of those is rice.
And the counties that I coverare San Joaquin, Sacramento,
Yolo Solano, and Contra Costacounties.
SPEAKER_02 (00:57):
Together, the UCCE Rice Farm Advisors seek to
provide relevant topicalresearch-packed information
relating to California riceproduction.
As of recording, it isofficially the beginning of
July.
And so kind of on theme withthat, we're sitting down with
(01:18):
Louisa Spino to talk about thefate of armyworms in rice as
we're approaching the first peakof armyworm population in the
2025 rice season.
Last year, we had a podcastepisode devoted to the second
peak of armyworm infestation.
So if you're interested inhearing more about that, you can
go find that in our backcatalog.
(01:38):
The armyworm is an insectcommonly found in rice fields,
and it becomes a pest whenpopulations reach high
densities.
Prior to 2015, we hadn't hadrecord of high effects of
armyworm defoliation in rice.
However, a serious armywormoutbreak occurred in 2015,
resulting in yield reductions ofup to 20% in some fields.
(02:01):
After 2015, research effortsfocused on controlling this
armyworm and actually led to theregistration of a chemical being
able to be used for control ofthis pest.
Now, infestation pressurefluctuates throughout the years,
and it's hard to tell if a yearis going to be a heavy armyworm
year prior to it actuallyshowing some damage.
(02:23):
But it's important to remainvigilant, especially at this
time of year.
And first and foremost, alwaysscout the fields, keep an eye
out, and see if there's anyworms or severe defoliation in
the field.
UNKNOWN (02:38):
Music
SPEAKER_02 (02:49):
Luis, thanks for being here today.
Hi,
SPEAKER_03 (02:52):
Sarah.
SPEAKER_02 (02:53):
Now I'm here to talk to you about pretty much
everyone's favorite mid-seasonpest, which is the armyworm.
As a recording, it's thebeginning of July, and so this
is kind of about the time wewant to be, well, we're kind of
past the time of starting tothink about armyworms, but now's
when we should be reallystarting to focus on it, right?
SPEAKER_03 (03:14):
Right.
Yeah, we're probably just on theother side of the armyworm, the
larval peak.
So actually this morning we werecounting worms on a trial.
And we started, this is our oneweek count.
So we did counts at three daysand then a week ago.
(03:34):
And yeah, our numbers went upquite a bit from our first count
on the untreated.
But I'm guessing, you know,given the size of the worms,
they're going, they're startingto pupate.
So they're probably going to,the numbers are going to start
going down now.
SPEAKER_02 (03:52):
Pretty low.
large worms then that you wereseeing?
SPEAKER_03 (03:55):
Pretty large, yes.
SPEAKER_02 (03:57):
And the worms that you were seeing, for the most
part, they were all armyworm.
They weren't fall armyworm.
They were our traditional truearmyworm.
SPEAKER_03 (04:06):
Right, yeah.
We don't have fall armyworm.
It is the true armyworm, the onethat we always see on rice.
Occasionally, we can also seewestern yellow striped armyworm,
but the When I have seen theWestern yellow stripe, it has
always been on the duck salad ormaybe on the red stem and is
(04:31):
eating those weeds, but not therice.
So it likes to eat the broadleafweeds and not rice.
And so, yeah, I think, you know,in the past, we always said that
both were a pest of rice, atleast in the past, you know, 15
years.
It's only been the true army.
SPEAKER_02 (04:52):
That's good.
Okay.
So maybe we should be promotingWestern yellow striped army
worms.
I
SPEAKER_03 (04:59):
wouldn't do that.
No, but they can.
They're an army worm too.
So they have that same behaviorwhere they move in mass into
areas where they can feed on.
And I've seen them move intoalfalfa fields, for example, a
few years ago.
And so, yeah, I don't know ifthey were to have an outbreak
(05:21):
like that and they were to moveinto rice, they might feed on
the rice.
Sometimes, you know, insects, ifthere's nothing left, nothing
else they can eat, they mighteat whatever's available and
they might eat the rice.
but so far I haven't seen themeating rice.
SPEAKER_02 (05:36):
Well, let's hope it stays that way.
As far as what you've beenseeing, you mentioned a trial
that you were working on earliertoday.
And I'll tell you, I've been outand about a little bit and the
rice experiment station and somefields I've been in lately, I've
been seeing not a lot ofdefoliation, but a lot of inch
or smaller sized worms.
(05:58):
Does that kind of concur withwhat you've been seeing?
SPEAKER_03 (06:00):
Yeah.
So yes, we've, We've seen thisyear certainly more worms than
the past two or three years.
And it's not outbreak levels.
And it is spotty.
Some fields you see largenumbers, other fields you don't
see very many.
There could be a little bit of adifference between areas.
(06:23):
So we have one of these fieldsthat we monitor constantly in
Ridgevale.
And over there, we saw wormsvery early on and they reached,
you know, they were prettylarge.
By now they're probably gone.
Well, that field had to besprayed because defoliation was
pretty uh, it wasn't a thresholdlevel, but it was really
(06:48):
approaching threshold level.
Uh, so yeah, those worms were alittle bigger.
So, you know, then we'reanother, or the, one of the
fields that we monitor, we endedup setting up a trial there and
those worms were a littlebehind, but now they're cycling,
you know, they're getting to thepoint that there will be cycling
out.
SPEAKER_02 (07:07):
And then kind of touching on that, um, because
you mentioned a lot of thedifferent sites that you're, uh,
tracking these numbers in aspart of the armyworm monitoring
network is that right
SPEAKER_03 (07:19):
yeah so yes the monitoring network so we use the
pheromone traps and and we havethese 15 sites and we check them
every week and then we we lookat the number of moths that
we're catching in the traps andso you know we've done this for
several years now maybe we'reapproaching maybe eight nine
(07:40):
years And so we've learned thatyou know, the number of moths
really doesn't give us muchinformation.
Some years we find huge numberof moths in the traps, but then
there's no worms in the field.
And we can talk about why later.
But we've learned that whatreally gives us the most
(08:04):
important information is when wereach the peak of moths in the
traps.
And so when we reach that peak,we know that That week and the
following week is when we'regoing to see the peak number of
worms of larvae in the field.
And so, you know, when you havehigh numbers of worms, those are
(08:29):
the ones that are going to bedefoliating and potentially
causing damage.
And that's when it's going to beeasier to find them.
So that's how we recommend usingthe traps or the information
from the traps is once youidentify, okay, we're at peak or
(08:50):
we reached the peak last weekbecause we check it every week.
So we know the peak happenedlast week.
Then that's the time to reallymonitor closely, look for worms.
And if needed, you know, atreatment can be made.
SPEAKER_02 (09:08):
Yeah.
So I guess kind of to distill itdown, the traps are a really
good way of seeing if there's apresence of moths, but not
necessarily the number of wormsthat might be in the field.
SPEAKER_03 (09:19):
Right.
Yeah.
So what we've seen is that thenumber of worms varies, like
every field is different.
So say we find 50 moths a nightin field A, 50 moths a night in
that field may mean two wormsper square foot but on field b
50 moths a night might meaneight worms per square foot so
(09:46):
it changes so we can make arecommendation based on the
number of moths because of thatso now why is that The pheromone
we use for the armyworm traps,for the moth traps, is a
pheromone that attracts males.
And so the males will mate withthe females, and the females
(10:07):
then lay their eggs.
But we're not catching thefemales, which are the ones that
will carry eggs.
Now, this is interesting.
Now, we know in nature that theratio of male-female is 1 to 1.
So in theory, if there's 100males, flying around.
There should be 100 femalesflying around.
(10:30):
So these army worms, they aremigratory.
And so they move, you know,across the landscape.
I suspect that they move intoour area coming from probably
from Southern California, maybeother areas south of us.
And they move into our area andthen they will continue moving
(10:52):
north and go all the way toCanada.
And so what happens and there'sa there's a recent paper that
was published this year,actually, where they from some
workers in Quebec in Canada.
And so they were trapping armyworms using light traps.
(11:13):
The light traps should attractmales and females equally, but
they were getting more malesthan females.
And so what they have been ableto deduct from that information
is that the movement of moths isnot one-to-one.
So the males will move and theywill fly while the females might
(11:39):
be migrating, but then theymight need to stop if they're
ready to fly.
lay eggs.
So they might stop in some areasto mate, lay eggs, but the males
will, you know, will continuemoving.
And so that difference seems tobe why some years, you know, we
might get a lot of moths, youknow, a lot of male moths, but
(12:03):
then there's no worms.
It's because, you know, there'snot enough females out there.
There's very few females.
When I say few, I'm the numberof females that would cause an
outbreak, right?
So that's, I think that kind ofsolves that mystery that, so why
(12:23):
are we not, even though we catchso many moths, why are we not
seeing worms in the field?
And it might be related to that.
So that, I really enjoyedreading that paper.
SPEAKER_02 (12:35):
That sounds like a really interesting paper.
We'll be sure to link to that inthe show notes for anybody who
wants to read that further.
SPEAKER_03 (12:41):
It's a paper from Lemire Hamel.
That's the last name of the mainauthor and it's on the Canadian
entomologist.
in 2025.
So anyway.
SPEAKER_02 (12:53):
Could it be, is it that there are fewer females or
just that the females are lessmobile?
SPEAKER_03 (12:59):
Well, I'll have to go back and read, but I think
there's fewer females arrivingat certain locations when
they're migrating.
And once the females go intoreproductive mode, they might
not move as much because theyhave to conserve energy to
produce eggs.
And so they might not fly aslong or, you know, as the
(13:23):
distances that the males do,because the males don't need to
save energy.
SPEAKER_02 (13:28):
No, they're kind of done doing their part.
They just need to fly.
SPEAKER_03 (13:31):
Right.
They just fly, you know, andhope that the females are around
when they get where they'regoing.
Right.
Yes.
SPEAKER_02 (13:36):
Well, that's really neat.
I mean, like you said,potentially a mystery cracked at
least a little bit to see maybesomething worthy of more
investigation.
SPEAKER_03 (13:45):
Right.
It makes sense.
And that this kind of explainswhy we don't always see huge
populations even though we see alot of a lot of moths
SPEAKER_02 (13:55):
well okay i'm kind of going back to this tracking
network i'm looking at it hereand it looks like across the
area where we do the monitoringit looks like some of the trap
areas haven't hit their peakmoth captures as of last week
some of them are approximatelyat peak and then some of them
saw their peak a couple of weeksago even i mean do we have an
(14:19):
explanation for that or is thatjust all part of the variability
we see?
SPEAKER_03 (14:23):
So I think there's variability.
So within a field, sometimes,you know, in each field that we
monitor with the traps, we havethree traps.
And so even within a field, sometraps, you know, peak maybe a
week earlier than other traps.
So there is some spatialvariability, you know, even at
the trap level.
(14:45):
But I think that there might bealso some differences in
geographic area areas.
So like I was saying earlier, wehave this field in Richvale
where we saw early on maybe alittle bit more activity on the
worms versus other fields, not alittle bit to the east, not
(15:06):
still in the area, but, youknow, closer to bigs.
And this other field was alittle behind.
So there, I think there might besome geographic differences.
Now, why?
I don't, I can't, you know, Ican't say what makes one field
different than another.
And it's the same reason whysome fields tend to see high
(15:28):
numbers versus other fieldsdon't seem to have a lot of
worms in them.
I don't know what the reason is,but there are some differences
like that.
So important to, you know, scoutPay attention to, you know, if
there's information from thearea, you can pay attention to
(15:48):
that.
But I think in general, theaverage that we send out with
the email, you know, with theupdates on the trapping, the
average, what we send is theaverage for the whole valley.
And that gives a good idea of,you know, where the populations
are.
SPEAKER_02 (16:06):
Well, you mentioned scouting.
Let's kind of get into that alittle bit.
Do you have recommendedtechniques for What time of day
to scout?
What area of the field or thebasin to scout?
Anything you want to touch onhere?
SPEAKER_03 (16:18):
Well, so, you know, the scouting is you got to look
for defoliation, but also yougot to look to see if there's
worms, right?
You don't want to seedefoliation, but maybe the worms
already cycled out.
So, you know, let's say you comeback from 4th of July weekend
next week and you might see somedefoliation, but the worms might
(16:41):
have already cycled out.
cycled out so there's no pointin doing any treatment so look
for worms you know look at thebase of the canopy the worms
like to hide especially inplaces where there's thick rice
and they like to be parallel tothe tillers and so those thick
(17:02):
areas that's where they'rehiding you know I know some
growers like to shake the riceand see how many fall in the
water and that works too youknow but you might miss the ones
that are right at the base of atthe water level you know just
just hiding there in the tillersand usually we see higher
(17:23):
densities in the borders itseems like that's where the
infestation starts so if you'rescouting you know you can check
those areas to see how it'sdoing but always take a look
further you know walk a littlebit into the field because there
might not be that many once yougo you know 40 50 feet into the
field.
(17:45):
So I think that would be what Irecommend.
The other thing, sometimes I getthe question, because the
threshold is by defoliation.
So we want to avoid getting tohigher than 25% defoliation,
which is a little tricky.
What is 25%?
You just kind of got to, youhave to guesstimate.
(18:07):
You can also count the worms,right?
And a lot of people do that.
It gives you another parameter.
So a few years ago, we did astudy where we were counting
worms and trying to correlatethat to defoliation level.
And whenever we had more thansix armyworms per square foot,
(18:28):
then we would start seeingdefoliation that was close to
25%.
So that's an informal threshold,you know, because we did it, but
we didn't have enough samples.
with high levels of defoliation.
This year would have been a goodyear to do that, but we were not
(18:48):
planning on doing it.
But if you're seeing more thansix, certainly if you're seeing
more than 10, then that'sconcerning.
And either keep a really closeeye on the rise, or if you're
seeing some importantdefoliation, then maybe consider
a treatment.
(19:08):
This year is tough with theprices, But you can wait.
So that's the other thing is,you know, you can wait.
One of the insecticides that wehave registered,
methoxyphenazide, that's a goodjob of controlling the armyworm
quickly.
So, you know, you spray and it'snot going to be immediate, but,
you know, at three days, you'llsee a good reduction.
(19:31):
A week later, you will see morethan 90% control.
So that's the good thing abouthaving a good product that works
is that, you know, you can wait.
until you are actually sure thatyou, you know, you need to
treat.
You want to avoid, you know,those preventive applications
that sometimes, because we had,you know, with pyrethroids that
(19:53):
were not working very well, somepeople were trying, well, maybe
if we put it early, we'll getthose little ones, but you don't
know if you're really going toneed a treatment or not.
So we want to get away fromthat.
SPEAKER_02 (20:05):
Yeah, not just spraying because you think you
might need it, actually sprayingwhen it's economical and most
effective against the pest andusing a product that can do that
SPEAKER_03 (20:16):
right and we have a product that can do that so
that's that's
SPEAKER_02 (20:20):
good rice is really pretty tolerant of defoliation i
mean especially at this stageright this first peak of army
worms is that i mean if even ifyou've got 10 15 defoliation is
there going to be an effect onyield later on the season
SPEAKER_03 (20:36):
now we've we've done so we've done trials where we
kept we defoliated rice now weWe did it artificially because
we couldn't have, you know.
SPEAKER_02 (20:44):
You couldn't raise army worms to graze your rice.
Yeah.
SPEAKER_03 (20:48):
It's hard to find places where you could have
different defoliation levels.
So we defoliated rice.
We, you know, we just usescissors and we did it across
several days to try to mimic howthe army worm does it.
And if we lose, if we lose 25%of the foliage, we don't see a
(21:10):
yield reduction.
But if we lose 50%, then westart seeing a percent
reduction.
And when we did it, we did itfor three years.
I think on average, we werelosing 4% of yield when we
defoliated 50%.
So if you imagine a field that'seaten half you will lose, or an
(21:31):
area that's eaten half, you willlose about, you know, if the
field produces 100 sacks, you'relosing four sacks.
SPEAKER_02 (21:38):
Which, I mean, granted, it's not insignificant,
but 50% defoliation, that'shuge.
That's a really large amount.
It's
SPEAKER_03 (21:46):
huge, and it looks very scary.
It looks terrible, right?
But the rice is tough, and itcan, you know, it loses some,
but it's not going to lose all.
When we defoliated the rice allthe way to the water level, So
we cut it all the way to thewater, you know, as best as we
could.
There's always some living thatstayed above the water.
(22:10):
Then we would find a good 25%yield reduction when we do that.
SPEAKER_02 (22:15):
And that would be 100% defoliation estimate.
SPEAKER_03 (22:19):
That's what we would call 100%, yeah.
And so we saw that, you know, in2015, right, 2015, when we had
the outbreak, some areas werejust, you know, it into the
water.
And so those fields probably sawa yield reduction.
But yeah, rice is pretty tough.
And so it can take a lot ofdefoliation.
(22:40):
The issue is, you know, okay, ifthese worms are eating and
you're already losing about aquarter of your foliage, they
can eat a lot very quickly.
And so you don't want to getanywhere more than 25%.
So that's why we make thethreshold 25% defoliation.
(23:02):
You don't want to get to 50%because then we know you're
going to lose yield.
SPEAKER_02 (23:06):
Let's say we've got a field, we think we're
approximately 25% defoliation.
We've still got worms in thefield that we're seeing.
What kind of, I guess, controlmethods or management options
are there for a grower, maybestarting cultural methods?
Let's talk about those first.
Does that primarily centeraround early season weed
(23:27):
management?
Or I guess that'd be before yousee the worm.
Yeah,
SPEAKER_03 (23:31):
I think early season weed management will have an
effect, I think.
We haven't done a formal studyon this, but I mean, many times
if you walk a field, you'll seethe water grass, you know, it's
all eaten up.
They'll eat the water grass.
And a lot of times it seems likeafter propanil sprays, those
(23:53):
worms that were on the watergrass kind of move to the rice
or start eating the rice.
That's kind of just an opinion.
observation you know we haven'tdone like i said a formal study
but it seems to be that way so ithink yeah you know grassy
fields might have offer more avariety of diet for the army
(24:14):
worms so that might might playto play a role but if yeah if
you get them you know andthere's a high number of them
and the defoliation is high,there's not much else we can do
other than an insecticide.
SPEAKER_02 (24:29):
And I think we've got, you've already mentioned
the chemical name of what wecall Intrepid, that's the trait
name.
And then there's also anotherone, different chemical name
that I can't think of right now,but Dimolin.
But that one has a differentpre-harvest interval, is that
right?
SPEAKER_03 (24:48):
Yeah, Dimolin.
So Dimolin is also a goodarmyworm product.
It works well.
It's a little slower thanIntrepid, but it does keep
control.
Yeah, it's got an 80-daypre-harvest interval.
So you have to be careful abouthow late you can put it on.
So on a typical armyworm yearand on a typical rice planting
(25:12):
year, you can still use it fordefoliation.
But once we get into the secondflight and the heading then if
there was a need for aninsecticide you couldn't use it
then so yeah so we have in theintrepid demilin the pyrethroids
uh that are common for otherpests are really they do not
(25:34):
work for our worms so i i woulddiscourage people to to use them
at all because we've done trialswe've seen fields sprayed uh you
know we've seen uh Pyrethro iscombined with Propanil.
Maybe control them when they'resmall, but they just don't work.
SPEAKER_02 (25:57):
Yeah, and so in that, you'd just be kind of
throwing money away if you triedto treat armyworms with
pyrethroids.
SPEAKER_03 (26:03):
Pretty much, yeah.
It's not doing anything.
SPEAKER_02 (26:06):
Now, what if I'm an organic grower?
Because these are obviouslychemicals that you're using in
conventional farming systems.
But if you're an organic growerwho's got a problem with
armyworms, are there options outthere for them?
SPEAKER_03 (26:18):
Well, you can use the BT products.
They're not very effective.
You know, over the years, we'veseen up to 50% of efficacy.
They just don't work as wellbecause by the time we see the
worms and we made the decisionto treat, the worms are too big.
The small worms, when BT wouldbe more effective, a lot of
(26:43):
times we just don't see them.
It's really hard to see them inrice.
They're hard to find.
So it kind of misses thatwindow.
And at that time also, we don'tknow if, yeah, it's going to be
enough population to causedefoliation.
So it's challenging.
(27:03):
The tools for organic growersare not the best.
But the BTs are available andthey will reduce the population
somewhat, but it's not going tobe as effective as the other,
the chemical options.
SPEAKER_02 (27:18):
Is there anything, I guess, in terms of research on
armyworms that you're working onthis year or in recent years?
SPEAKER_03 (27:27):
Well, this year, mentioning earlier, we did an
insecticide trial.
And so there is a product thatwe're hoping it's going to be
available soon.
maybe next year, and it works asgood as Intrepid.
So it will give us a, and it's adifferent mode of action, so
it'll give us a really goodrotational alternative.
(27:51):
We looked at another productalso that's a biological, it's a
fungus that would colonize thearmyworm and kill them.
But unfortunately, it did notreally do much.
SPEAKER_02 (28:04):
Oh man, because that sounds exciting.
SPEAKER_03 (28:06):
Right, yeah.
And these products work in othersystems, but again, rice is just
not very good.
The way we use these productsdon't work as well.
SPEAKER_02 (28:22):
Yeah, it's just rice is interesting in a lot of ways.
A lot of things that might workin other row crops don't tend to
always transfer over.
SPEAKER_03 (28:31):
Right, yes.
SPEAKER_02 (28:33):
Well, Luis, thanks for talking with me today.
Anything else you want to bringup while we're on?
SPEAKER_03 (28:37):
Yeah, and well, you know, I think, like I said
earlier, we're seeing more wormsthan the past few years.
I think, you know, growersshould keep that in mind.
We're already...
past that first peak, butthere's a second one.
And we'll see if thosepopulations track this first
(29:00):
infestation.
And if they do, just keep an eyeon the field.
The second one's a littletrickier, because the injury
occurs on the panicle.
And once it happens, there's noreducing that.
Once the injury is done, it'sdone.
(29:20):
But we don't know exactly atwhat point it happens.
Does it happen as the panicle'scoming out?
Can it happen once the panicle'sout and it's already filled?
What is the window ofsusceptibility?
We haven't been able todetermine that.
So I think it's just a matterof...
being aware that, okay, theremight be some worms and just
(29:41):
keep an eye on it.
SPEAKER_02 (29:43):
That's a great note, Luis.
And actually I'll link theepisode we did last year on the
second peak of army worms in theshow notes.
So if people want to just get anice one, two punch of first
peak, second peak army worms,we'll have that ready for them.
SPEAKER_03 (29:57):
Okay, great.
SPEAKER_02 (29:57):
Well, Luis, thank you so much.
And we will see you around.
No
SPEAKER_03 (30:02):
problem.
Thank you.
SPEAKER_02 (30:18):
We've got a couple of upcoming events that are
rapidly approaching.
The first event that's up on ourschedule is the Rice Production
Workshop, which is a workshop wehold every two years to cover
the basic principles andpractices of rice production in
California.
This event will take place July23rd and July 24th, 2025.
(30:40):
This is a two-day workshop.
These will be two all days, soit will start at 8.30 a.m.
and go till 3.30 p.m.
and take place at the UC A&Rbuilding on 2801 2nd Street in
Davis.
Registration is required forthis event and if you go to our
UC Rice website there is a linkfor that registration.
(31:03):
Our next upcoming event will bethe Weedy Rice Workshop which
will take place August 5th, 2025from 10 a.m.
to 1 15 p.m.
at the Roberts Union Farm Centerin Stockton, California.
This will be a workshop devotedto the history and current
management practices of weedyrice in California.
(31:25):
Registration is not required forthis event.
Our final upcoming event forthis season is the annual Rice
Field Day, which takes placeevery year on the last Wednesday
of August, which is August 27,2025.
It starts promptly in themorning, so be sure to get your
coffee and donuts when the fieldday starts, and it will take
(31:45):
place at the Rice ExperimentStation at 95 And as always,
stay tuned for some great talksand a delicious lunch.
For more information about theseand other upcoming events, feel
free to check out our resources,which include the UC Rice blog
(32:07):
and the UC Agronomy Ricewebsite.
In terms of other resources youmay want to take advantage of,
you can also look at ournewsletters, which include Rice
Briefs, which covers Clusiolo,Rice Notes, which covers Yuba
Stutter, Rice Leaf, which coversButte and Glen, and Field Notes,
which covers rice in the Deltaregion of California.
(32:30):
Thanks for listening to Thoughtson Rice, a University of
California Cooperative Extensionpodcast from University of
California Agriculture andNatural Resources.
You can find out more about thispodcast on our website,
thoughtsonrice.buzzsprout.com.
We'd love to hear from you,whether it's from using our text
(32:52):
link in the show notes, a surveysubmission in our feedback form,
also in the show notes, or in acomment or rating on your
podcast streaming service.
of choice.
You can also email us with anycomments, questions, or concerns
at thoughtsonrice atucdavis.edu.
Thanks for sticking with us overthis planting hiatus earlier
(33:14):
this spring.
Rice season is well underway,and we hope you stay safe this
season.
And remember, like the growerslike to say, have a rice life.
Mention of an agrochemical doesnot constitute recommendation,
merely the sharing of researchfindings.
Always follow the label.
The label is the law.
(33:35):
Find out more at ipm.ucanr.edu.
The views, thoughts, andopinions expressed are the
speaker's own and do notrepresent the views, thoughts,
and opinions of the Universityof California.
The material and informationpresented here is for general
purposes only.
The University of Californianame and all forms and
abbreviations are the propertyof its owner, and its use does
(33:57):
not imply endorsement of oropposition to any specific
organization, product, orservice.
Hello and welcome to Thoughts on Rice, a podcast
hosted by the University ofCalifornia Cooperative Extension
Rice Advisors.
I'm one of your hosts, SarahMarchionish, and I'm a rice farm
(00:21):
advisor for Colusa and Yolocounties.
SPEAKER_00 (00:25):
I'm Whitney from DeForest.
I'm the Cooperative ExtensionRice Advisor for Sutter, Yuba,
Placer, and Sacramento counties.
SPEAKER_03 (00:32):
My name is Luis Espino.
I'm the Rice Farming SystemsAdvisor for Butte
SPEAKER_01 (00:38):
and Glynn counties.
I'm Michelle Leinfelder-Miles.
I'm a Farm Advisor in the Deltaregion.
I work on all sorts of fieldcrops, grains and forages.
but one of those is rice.
And the counties that I coverare San Joaquin, Sacramento,
Yolo Solano, and Contra Costacounties.
SPEAKER_02 (00:57):
Together, the UCCE Rice Farm Advisors seek to
provide relevant topicalresearch-packed information
relating to California riceproduction.
As of recording, it isofficially the beginning of
July.
And so kind of on theme withthat, we're sitting down with
(01:18):
Louisa Spino to talk about thefate of armyworms in rice as
we're approaching the first peakof armyworm population in the
2025 rice season.
Last year, we had a podcastepisode devoted to the second
peak of armyworm infestation.
So if you're interested inhearing more about that, you can
go find that in our backcatalog.
(01:38):
The armyworm is an insectcommonly found in rice fields,
and it becomes a pest whenpopulations reach high
densities.
Prior to 2015, we hadn't hadrecord of high effects of
armyworm defoliation in rice.
However, a serious armywormoutbreak occurred in 2015,
resulting in yield reductions ofup to 20% in some fields.
(02:01):
After 2015, research effortsfocused on controlling this
armyworm and actually led to theregistration of a chemical being
able to be used for control ofthis pest.
Now, infestation pressurefluctuates throughout the years,
and it's hard to tell if a yearis going to be a heavy armyworm
year prior to it actuallyshowing some damage.
(02:23):
But it's important to remainvigilant, especially at this
time of year.
And first and foremost, alwaysscout the fields, keep an eye
out, and see if there's anyworms or severe defoliation in
the field.
UNKNOWN (02:38):
Music
SPEAKER_02 (02:49):
Luis, thanks for being here today.
Hi,
SPEAKER_03 (02:52):
Sarah.
SPEAKER_02 (02:53):
Now I'm here to talk to you about pretty much
everyone's favorite mid-seasonpest, which is the armyworm.
As a recording, it's thebeginning of July, and so this
is kind of about the time wewant to be, well, we're kind of
past the time of starting tothink about armyworms, but now's
when we should be reallystarting to focus on it, right?
SPEAKER_03 (03:14):
Right.
Yeah, we're probably just on theother side of the armyworm, the
larval peak.
So actually this morning we werecounting worms on a trial.
And we started, this is our oneweek count.
So we did counts at three daysand then a week ago.
(03:34):
And yeah, our numbers went upquite a bit from our first count
on the untreated.
But I'm guessing, you know,given the size of the worms,
they're going, they're startingto pupate.
So they're probably going to,the numbers are going to start
going down now.
SPEAKER_02 (03:52):
Pretty low.
large worms then that you wereseeing?
SPEAKER_03 (03:55):
Pretty large, yes.
SPEAKER_02 (03:57):
And the worms that you were seeing, for the most
part, they were all armyworm.
They weren't fall armyworm.
They were our traditional truearmyworm.
SPEAKER_03 (04:06):
Right, yeah.
We don't have fall armyworm.
It is the true armyworm, the onethat we always see on rice.
Occasionally, we can also seewestern yellow striped armyworm,
but the When I have seen theWestern yellow stripe, it has
always been on the duck salad ormaybe on the red stem and is
(04:31):
eating those weeds, but not therice.
So it likes to eat the broadleafweeds and not rice.
And so, yeah, I think, you know,in the past, we always said that
both were a pest of rice, atleast in the past, you know, 15
years.
It's only been the true army.
SPEAKER_02 (04:52):
That's good.
Okay.
So maybe we should be promotingWestern yellow striped army
worms.
I
SPEAKER_03 (04:59):
wouldn't do that.
No, but they can.
They're an army worm too.
So they have that same behaviorwhere they move in mass into
areas where they can feed on.
And I've seen them move intoalfalfa fields, for example, a
few years ago.
And so, yeah, I don't know ifthey were to have an outbreak
(05:21):
like that and they were to moveinto rice, they might feed on
the rice.
Sometimes, you know, insects, ifthere's nothing left, nothing
else they can eat, they mighteat whatever's available and
they might eat the rice.
but so far I haven't seen themeating rice.
SPEAKER_02 (05:36):
Well, let's hope it stays that way.
As far as what you've beenseeing, you mentioned a trial
that you were working on earliertoday.
And I'll tell you, I've been outand about a little bit and the
rice experiment station and somefields I've been in lately, I've
been seeing not a lot ofdefoliation, but a lot of inch
or smaller sized worms.
(05:58):
Does that kind of concur withwhat you've been seeing?
SPEAKER_03 (06:00):
Yeah.
So yes, we've, We've seen thisyear certainly more worms than
the past two or three years.
And it's not outbreak levels.
And it is spotty.
Some fields you see largenumbers, other fields you don't
see very many.
There could be a little bit of adifference between areas.
(06:23):
So we have one of these fieldsthat we monitor constantly in
Ridgevale.
And over there, we saw wormsvery early on and they reached,
you know, they were prettylarge.
By now they're probably gone.
Well, that field had to besprayed because defoliation was
pretty uh, it wasn't a thresholdlevel, but it was really
(06:48):
approaching threshold level.
Uh, so yeah, those worms were alittle bigger.
So, you know, then we'reanother, or the, one of the
fields that we monitor, we endedup setting up a trial there and
those worms were a littlebehind, but now they're cycling,
you know, they're getting to thepoint that there will be cycling
out.
SPEAKER_02 (07:07):
And then kind of touching on that, um, because
you mentioned a lot of thedifferent sites that you're, uh,
tracking these numbers in aspart of the armyworm monitoring
network is that right
SPEAKER_03 (07:19):
yeah so yes the monitoring network so we use the
pheromone traps and and we havethese 15 sites and we check them
every week and then we we lookat the number of moths that
we're catching in the traps andso you know we've done this for
several years now maybe we'reapproaching maybe eight nine
(07:40):
years And so we've learned thatyou know, the number of moths
really doesn't give us muchinformation.
Some years we find huge numberof moths in the traps, but then
there's no worms in the field.
And we can talk about why later.
But we've learned that whatreally gives us the most
(08:04):
important information is when wereach the peak of moths in the
traps.
And so when we reach that peak,we know that That week and the
following week is when we'regoing to see the peak number of
worms of larvae in the field.
And so, you know, when you havehigh numbers of worms, those are
(08:29):
the ones that are going to bedefoliating and potentially
causing damage.
And that's when it's going to beeasier to find them.
So that's how we recommend usingthe traps or the information
from the traps is once youidentify, okay, we're at peak or
(08:50):
we reached the peak last weekbecause we check it every week.
So we know the peak happenedlast week.
Then that's the time to reallymonitor closely, look for worms.
And if needed, you know, atreatment can be made.
SPEAKER_02 (09:08):
Yeah.
So I guess kind of to distill itdown, the traps are a really
good way of seeing if there's apresence of moths, but not
necessarily the number of wormsthat might be in the field.
SPEAKER_03 (09:19):
Right.
Yeah.
So what we've seen is that thenumber of worms varies, like
every field is different.
So say we find 50 moths a nightin field A, 50 moths a night in
that field may mean two wormsper square foot but on field b
50 moths a night might meaneight worms per square foot so
(09:46):
it changes so we can make arecommendation based on the
number of moths because of thatso now why is that The pheromone
we use for the armyworm traps,for the moth traps, is a
pheromone that attracts males.
And so the males will mate withthe females, and the females
(10:07):
then lay their eggs.
But we're not catching thefemales, which are the ones that
will carry eggs.
Now, this is interesting.
Now, we know in nature that theratio of male-female is 1 to 1.
So in theory, if there's 100males, flying around.
There should be 100 femalesflying around.
(10:30):
So these army worms, they aremigratory.
And so they move, you know,across the landscape.
I suspect that they move intoour area coming from probably
from Southern California, maybeother areas south of us.
And they move into our area andthen they will continue moving
(10:52):
north and go all the way toCanada.
And so what happens and there'sa there's a recent paper that
was published this year,actually, where they from some
workers in Quebec in Canada.
And so they were trapping armyworms using light traps.
(11:13):
The light traps should attractmales and females equally, but
they were getting more malesthan females.
And so what they have been ableto deduct from that information
is that the movement of moths isnot one-to-one.
So the males will move and theywill fly while the females might
(11:39):
be migrating, but then theymight need to stop if they're
ready to fly.
lay eggs.
So they might stop in some areasto mate, lay eggs, but the males
will, you know, will continuemoving.
And so that difference seems tobe why some years, you know, we
might get a lot of moths, youknow, a lot of male moths, but
(12:03):
then there's no worms.
It's because, you know, there'snot enough females out there.
There's very few females.
When I say few, I'm the numberof females that would cause an
outbreak, right?
So that's, I think that kind ofsolves that mystery that, so why
(12:23):
are we not, even though we catchso many moths, why are we not
seeing worms in the field?
And it might be related to that.
So that, I really enjoyedreading that paper.
SPEAKER_02 (12:35):
That sounds like a really interesting paper.
We'll be sure to link to that inthe show notes for anybody who
wants to read that further.
SPEAKER_03 (12:41):
It's a paper from Lemire Hamel.
That's the last name of the mainauthor and it's on the Canadian
entomologist.
in 2025.
So anyway.
SPEAKER_02 (12:53):
Could it be, is it that there are fewer females or
just that the females are lessmobile?
SPEAKER_03 (12:59):
Well, I'll have to go back and read, but I think
there's fewer females arrivingat certain locations when
they're migrating.
And once the females go intoreproductive mode, they might
not move as much because theyhave to conserve energy to
produce eggs.
And so they might not fly aslong or, you know, as the
(13:23):
distances that the males do,because the males don't need to
save energy.
SPEAKER_02 (13:28):
No, they're kind of done doing their part.
They just need to fly.
SPEAKER_03 (13:31):
Right.
They just fly, you know, andhope that the females are around
when they get where they'regoing.
Right.
Yes.
SPEAKER_02 (13:36):
Well, that's really neat.
I mean, like you said,potentially a mystery cracked at
least a little bit to see maybesomething worthy of more
investigation.
SPEAKER_03 (13:45):
Right.
It makes sense.
And that this kind of explainswhy we don't always see huge
populations even though we see alot of a lot of moths
SPEAKER_02 (13:55):
well okay i'm kind of going back to this tracking
network i'm looking at it hereand it looks like across the
area where we do the monitoringit looks like some of the trap
areas haven't hit their peakmoth captures as of last week
some of them are approximatelyat peak and then some of them
saw their peak a couple of weeksago even i mean do we have an
(14:19):
explanation for that or is thatjust all part of the variability
we see?
SPEAKER_03 (14:23):
So I think there's variability.
So within a field, sometimes,you know, in each field that we
monitor with the traps, we havethree traps.
And so even within a field, sometraps, you know, peak maybe a
week earlier than other traps.
So there is some spatialvariability, you know, even at
the trap level.
(14:45):
But I think that there might bealso some differences in
geographic area areas.
So like I was saying earlier, wehave this field in Richvale
where we saw early on maybe alittle bit more activity on the
worms versus other fields, not alittle bit to the east, not
(15:06):
still in the area, but, youknow, closer to bigs.
And this other field was alittle behind.
So there, I think there might besome geographic differences.
Now, why?
I don't, I can't, you know, Ican't say what makes one field
different than another.
And it's the same reason whysome fields tend to see high
(15:28):
numbers versus other fieldsdon't seem to have a lot of
worms in them.
I don't know what the reason is,but there are some differences
like that.
So important to, you know, scoutPay attention to, you know, if
there's information from thearea, you can pay attention to
(15:48):
that.
But I think in general, theaverage that we send out with
the email, you know, with theupdates on the trapping, the
average, what we send is theaverage for the whole valley.
And that gives a good idea of,you know, where the populations
are.
SPEAKER_02 (16:06):
Well, you mentioned scouting.
Let's kind of get into that alittle bit.
Do you have recommendedtechniques for What time of day
to scout?
What area of the field or thebasin to scout?
Anything you want to touch onhere?
SPEAKER_03 (16:18):
Well, so, you know, the scouting is you got to look
for defoliation, but also yougot to look to see if there's
worms, right?
You don't want to seedefoliation, but maybe the worms
already cycled out.
So, you know, let's say you comeback from 4th of July weekend
next week and you might see somedefoliation, but the worms might
(16:41):
have already cycled out.
cycled out so there's no pointin doing any treatment so look
for worms you know look at thebase of the canopy the worms
like to hide especially inplaces where there's thick rice
and they like to be parallel tothe tillers and so those thick
(17:02):
areas that's where they'rehiding you know I know some
growers like to shake the riceand see how many fall in the
water and that works too youknow but you might miss the ones
that are right at the base of atthe water level you know just
just hiding there in the tillersand usually we see higher
(17:23):
densities in the borders itseems like that's where the
infestation starts so if you'rescouting you know you can check
those areas to see how it'sdoing but always take a look
further you know walk a littlebit into the field because there
might not be that many once yougo you know 40 50 feet into the
field.
(17:45):
So I think that would be what Irecommend.
The other thing, sometimes I getthe question, because the
threshold is by defoliation.
So we want to avoid getting tohigher than 25% defoliation,
which is a little tricky.
What is 25%?
You just kind of got to, youhave to guesstimate.
(18:07):
You can also count the worms,right?
And a lot of people do that.
It gives you another parameter.
So a few years ago, we did astudy where we were counting
worms and trying to correlatethat to defoliation level.
And whenever we had more thansix armyworms per square foot,
(18:28):
then we would start seeingdefoliation that was close to
25%.
So that's an informal threshold,you know, because we did it, but
we didn't have enough samples.
with high levels of defoliation.
This year would have been a goodyear to do that, but we were not
(18:48):
planning on doing it.
But if you're seeing more thansix, certainly if you're seeing
more than 10, then that'sconcerning.
And either keep a really closeeye on the rise, or if you're
seeing some importantdefoliation, then maybe consider
a treatment.
(19:08):
This year is tough with theprices, But you can wait.
So that's the other thing is,you know, you can wait.
One of the insecticides that wehave registered,
methoxyphenazide, that's a goodjob of controlling the armyworm
quickly.
So, you know, you spray and it'snot going to be immediate, but,
you know, at three days, you'llsee a good reduction.
(19:31):
A week later, you will see morethan 90% control.
So that's the good thing abouthaving a good product that works
is that, you know, you can wait.
until you are actually sure thatyou, you know, you need to
treat.
You want to avoid, you know,those preventive applications
that sometimes, because we had,you know, with pyrethroids that
(19:53):
were not working very well, somepeople were trying, well, maybe
if we put it early, we'll getthose little ones, but you don't
know if you're really going toneed a treatment or not.
So we want to get away fromthat.
SPEAKER_02 (20:05):
Yeah, not just spraying because you think you
might need it, actually sprayingwhen it's economical and most
effective against the pest andusing a product that can do that
SPEAKER_03 (20:16):
right and we have a product that can do that so
that's that's
SPEAKER_02 (20:20):
good rice is really pretty tolerant of defoliation i
mean especially at this stageright this first peak of army
worms is that i mean if even ifyou've got 10 15 defoliation is
there going to be an effect onyield later on the season
SPEAKER_03 (20:36):
now we've we've done so we've done trials where we
kept we defoliated rice now weWe did it artificially because
we couldn't have, you know.
SPEAKER_02 (20:44):
You couldn't raise army worms to graze your rice.
Yeah.
SPEAKER_03 (20:48):
It's hard to find places where you could have
different defoliation levels.
So we defoliated rice.
We, you know, we just usescissors and we did it across
several days to try to mimic howthe army worm does it.
And if we lose, if we lose 25%of the foliage, we don't see a
(21:10):
yield reduction.
But if we lose 50%, then westart seeing a percent
reduction.
And when we did it, we did itfor three years.
I think on average, we werelosing 4% of yield when we
defoliated 50%.
So if you imagine a field that'seaten half you will lose, or an
(21:31):
area that's eaten half, you willlose about, you know, if the
field produces 100 sacks, you'relosing four sacks.
SPEAKER_02 (21:38):
Which, I mean, granted, it's not insignificant,
but 50% defoliation, that'shuge.
That's a really large amount.
It's
SPEAKER_03 (21:46):
huge, and it looks very scary.
It looks terrible, right?
But the rice is tough, and itcan, you know, it loses some,
but it's not going to lose all.
When we defoliated the rice allthe way to the water level, So
we cut it all the way to thewater, you know, as best as we
could.
There's always some living thatstayed above the water.
(22:10):
Then we would find a good 25%yield reduction when we do that.
SPEAKER_02 (22:15):
And that would be 100% defoliation estimate.
SPEAKER_03 (22:19):
That's what we would call 100%, yeah.
And so we saw that, you know, in2015, right, 2015, when we had
the outbreak, some areas werejust, you know, it into the
water.
And so those fields probably sawa yield reduction.
But yeah, rice is pretty tough.
And so it can take a lot ofdefoliation.
(22:40):
The issue is, you know, okay, ifthese worms are eating and
you're already losing about aquarter of your foliage, they
can eat a lot very quickly.
And so you don't want to getanywhere more than 25%.
So that's why we make thethreshold 25% defoliation.
(23:02):
You don't want to get to 50%because then we know you're
going to lose yield.
SPEAKER_02 (23:06):
Let's say we've got a field, we think we're
approximately 25% defoliation.
We've still got worms in thefield that we're seeing.
What kind of, I guess, controlmethods or management options
are there for a grower, maybestarting cultural methods?
Let's talk about those first.
Does that primarily centeraround early season weed
(23:27):
management?
Or I guess that'd be before yousee the worm.
Yeah,
SPEAKER_03 (23:31):
I think early season weed management will have an
effect, I think.
We haven't done a formal studyon this, but I mean, many times
if you walk a field, you'll seethe water grass, you know, it's
all eaten up.
They'll eat the water grass.
And a lot of times it seems likeafter propanil sprays, those
(23:53):
worms that were on the watergrass kind of move to the rice
or start eating the rice.
That's kind of just an opinion.
observation you know we haven'tdone like i said a formal study
but it seems to be that way so ithink yeah you know grassy
fields might have offer more avariety of diet for the army
(24:14):
worms so that might might playto play a role but if yeah if
you get them you know andthere's a high number of them
and the defoliation is high,there's not much else we can do
other than an insecticide.
SPEAKER_02 (24:29):
And I think we've got, you've already mentioned
the chemical name of what wecall Intrepid, that's the trait
name.
And then there's also anotherone, different chemical name
that I can't think of right now,but Dimolin.
But that one has a differentpre-harvest interval, is that
right?
SPEAKER_03 (24:48):
Yeah, Dimolin.
So Dimolin is also a goodarmyworm product.
It works well.
It's a little slower thanIntrepid, but it does keep
control.
Yeah, it's got an 80-daypre-harvest interval.
So you have to be careful abouthow late you can put it on.
So on a typical armyworm yearand on a typical rice planting
(25:12):
year, you can still use it fordefoliation.
But once we get into the secondflight and the heading then if
there was a need for aninsecticide you couldn't use it
then so yeah so we have in theintrepid demilin the pyrethroids
uh that are common for otherpests are really they do not
(25:34):
work for our worms so i i woulddiscourage people to to use them
at all because we've done trialswe've seen fields sprayed uh you
know we've seen uh Pyrethro iscombined with Propanil.
Maybe control them when they'resmall, but they just don't work.
SPEAKER_02 (25:57):
Yeah, and so in that, you'd just be kind of
throwing money away if you triedto treat armyworms with
pyrethroids.
SPEAKER_03 (26:03):
Pretty much, yeah.
It's not doing anything.
SPEAKER_02 (26:06):
Now, what if I'm an organic grower?
Because these are obviouslychemicals that you're using in
conventional farming systems.
But if you're an organic growerwho's got a problem with
armyworms, are there options outthere for them?
SPEAKER_03 (26:18):
Well, you can use the BT products.
They're not very effective.
You know, over the years, we'veseen up to 50% of efficacy.
They just don't work as wellbecause by the time we see the
worms and we made the decisionto treat, the worms are too big.
The small worms, when BT wouldbe more effective, a lot of
(26:43):
times we just don't see them.
It's really hard to see them inrice.
They're hard to find.
So it kind of misses thatwindow.
And at that time also, we don'tknow if, yeah, it's going to be
enough population to causedefoliation.
So it's challenging.
(27:03):
The tools for organic growersare not the best.
But the BTs are available andthey will reduce the population
somewhat, but it's not going tobe as effective as the other,
the chemical options.
SPEAKER_02 (27:18):
Is there anything, I guess, in terms of research on
armyworms that you're working onthis year or in recent years?
SPEAKER_03 (27:27):
Well, this year, mentioning earlier, we did an
insecticide trial.
And so there is a product thatwe're hoping it's going to be
available soon.
maybe next year, and it works asgood as Intrepid.
So it will give us a, and it's adifferent mode of action, so
it'll give us a really goodrotational alternative.
(27:51):
We looked at another productalso that's a biological, it's a
fungus that would colonize thearmyworm and kill them.
But unfortunately, it did notreally do much.
SPEAKER_02 (28:04):
Oh man, because that sounds exciting.
SPEAKER_03 (28:06):
Right, yeah.
And these products work in othersystems, but again, rice is just
not very good.
The way we use these productsdon't work as well.
SPEAKER_02 (28:22):
Yeah, it's just rice is interesting in a lot of ways.
A lot of things that might workin other row crops don't tend to
always transfer over.
SPEAKER_03 (28:31):
Right, yes.
SPEAKER_02 (28:33):
Well, Luis, thanks for talking with me today.
Anything else you want to bringup while we're on?
SPEAKER_03 (28:37):
Yeah, and well, you know, I think, like I said
earlier, we're seeing more wormsthan the past few years.
I think, you know, growersshould keep that in mind.
We're already...
past that first peak, butthere's a second one.
And we'll see if thosepopulations track this first
(29:00):
infestation.
And if they do, just keep an eyeon the field.
The second one's a littletrickier, because the injury
occurs on the panicle.
And once it happens, there's noreducing that.
Once the injury is done, it'sdone.
(29:20):
But we don't know exactly atwhat point it happens.
Does it happen as the panicle'scoming out?
Can it happen once the panicle'sout and it's already filled?
What is the window ofsusceptibility?
We haven't been able todetermine that.
So I think it's just a matterof...
being aware that, okay, theremight be some worms and just
(29:41):
keep an eye on it.
SPEAKER_02 (29:43):
That's a great note, Luis.
And actually I'll link theepisode we did last year on the
second peak of army worms in theshow notes.
So if people want to just get anice one, two punch of first
peak, second peak army worms,we'll have that ready for them.
SPEAKER_03 (29:57):
Okay, great.
SPEAKER_02 (29:57):
Well, Luis, thank you so much.
And we will see you around.
No
SPEAKER_03 (30:02):
problem.
Thank you.
SPEAKER_02 (30:18):
We've got a couple of upcoming events that are
rapidly approaching.
The first event that's up on ourschedule is the Rice Production
Workshop, which is a workshop wehold every two years to cover
the basic principles andpractices of rice production in
California.
This event will take place July23rd and July 24th, 2025.
(30:40):
This is a two-day workshop.
These will be two all days, soit will start at 8.30 a.m.
and go till 3.30 p.m.
and take place at the UC A&Rbuilding on 2801 2nd Street in
Davis.
Registration is required forthis event and if you go to our
UC Rice website there is a linkfor that registration.
(31:03):
Our next upcoming event will bethe Weedy Rice Workshop which
will take place August 5th, 2025from 10 a.m.
to 1 15 p.m.
at the Roberts Union Farm Centerin Stockton, California.
This will be a workshop devotedto the history and current
management practices of weedyrice in California.
(31:25):
Registration is not required forthis event.
Our final upcoming event forthis season is the annual Rice
Field Day, which takes placeevery year on the last Wednesday
of August, which is August 27,2025.
It starts promptly in themorning, so be sure to get your
coffee and donuts when the fieldday starts, and it will take
(31:45):
place at the Rice ExperimentStation at 95 And as always,
stay tuned for some great talksand a delicious lunch.
For more information about theseand other upcoming events, feel
free to check out our resources,which include the UC Rice blog
(32:07):
and the UC Agronomy Ricewebsite.
In terms of other resources youmay want to take advantage of,
you can also look at ournewsletters, which include Rice
Briefs, which covers Clusiolo,Rice Notes, which covers Yuba
Stutter, Rice Leaf, which coversButte and Glen, and Field Notes,
which covers rice in the Deltaregion of California.
(32:30):
Thanks for listening to Thoughtson Rice, a University of
California Cooperative Extensionpodcast from University of
California Agriculture andNatural Resources.
You can find out more about thispodcast on our website,
thoughtsonrice.buzzsprout.com.
We'd love to hear from you,whether it's from using our text
(32:52):
link in the show notes, a surveysubmission in our feedback form,
also in the show notes, or in acomment or rating on your
podcast streaming service.
of choice.
You can also email us with anycomments, questions, or concerns
at thoughtsonrice atucdavis.edu.
Thanks for sticking with us overthis planting hiatus earlier
(33:14):
this spring.
Rice season is well underway,and we hope you stay safe this
season.
And remember, like the growerslike to say, have a rice life.
Mention of an agrochemical doesnot constitute recommendation,
merely the sharing of researchfindings.
Always follow the label.
The label is the law.
(33:35):
Find out more at ipm.ucanr.edu.
The views, thoughts, andopinions expressed are the
speaker's own and do notrepresent the views, thoughts,
and opinions of the Universityof California.
The material and informationpresented here is for general
purposes only.
The University of Californianame and all forms and
abbreviations are the propertyof its owner, and its use does
(33:57):
not imply endorsement of oropposition to any specific
organization, product, orservice.
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