Greetings, growers worldwide. Jordan River here back with more grow cast mining into the good content today. We've got Matthew gates back on the line. We're talking about powdery mildew and how intelligent it is and how it learns things. We also talk about borer, miner bugs, insects, pests, and how you need to treat them differently than a lot of other pests. It's a really solid episode. I know you're gonna love it before we jump into it with Matthew gates, though, shout out to AC infinity. That's right. AC Infinity has been with us for a long time. Acinity.com, for all your growing needs, tents, lights, fans, the best in the game. And grow cast one five gets you the biggest savings there on the site, plus new to Amazon. If you use code growcast One five on your AC infinity Amazon order, you now get 10% off on Amazon. So they've raised that code a little bit. I think it used to be like 5% so if you prefer the Prime shipping, go to amazon.com. Whatever AC infinity product you need, put it in your cart. Use code grow cast one five, you'll get 10% off or go right to AC infinity.com use code growth cast one five, and you still get free shipping on orders $99 or more. So like I said, grab a Grow Tent kit. There's no better place to just grab a complete kit. Their ion board lights are nice and affordable. Their ion bar lights are fantastic to use for flowering, tents of all different sizes. Like I said, the best aeration in the game. Go check it out. Grow, cast one five works on the website, gives you 10% off on Amazon on all AC infinity products. Huge shout out to AC infinity. Thank you, and thank you listeners for using our code. It helps us, it helps you, it helps them. And it's all at AC infinity.com with code grow cast, one five. All right, let's get to it with Matthew gates, thank you for listening and enjoy the show. Hello, podcast listeners. You are now listening to grow cast. I'm your host, Jordan River, and I want to thank you for tuning in again today. Before we get started as always, I urge you to share the show, tell a grower about growcast, and, better yet, turn a smoker on to growing. It's how you can help us on our mission of overgrow. Make sure you're subscribed and hit growcast.com the brand new website. There you'll find the membership, the seeds, the classes, it's all there. Special. Thank you to the members. Speaking of which, our grand fino hunt just started on the underway in growcast membership, so jump in. It's not too late. You got until March 1 to pop seeds. Come and join us, folks, grow cast.com/hunt, I'd love to see you there, but let me tell you, if you're doing a fino Hunt, a big old fino hunt, the last thing you want to get is a pest problem. That's what we're talking about today. My buddy from xenthanol Consulting, Matthew gates is back on the line. You know him. You love him. What's up? Matthew, how are you doing? Man, I'm doing good. I'm excited to talk tonight about pests, because we're doing this big, grand fino hunt, right? A lot of people hunting through packs. And it got me thinking, when you get those tents packed in tightly, when you push your plant count and make that canopy nice and dense. Oh my God, dude, it's like, sometimes you're asking for it with a pest issue, and if a pest gets in, it's like, eating. You know what I'm saying? Yeah,
it's just, you know what are you gonna do?
Like, can't tell, you can't tell what the full extent was. It's such a heartbreak. Yeah, absolutely,
man. So I want to talk to you today about a couple different pest topics. We're talking about powdery mildew. We're talking about some stuff that I've dealt with recently. We're talking about pests ability to develop resistances. I think that's a term that gets thrown around a lot, and I want to talk to you about all of it, man. But let's start from the top. What have you been up to since last we spoke? What have you been working on? What's been going on in
your world? Well, first I want to say that Autumn
and summer has been very productive for me in general. I was able to help with Cornell University get a New York State guide book out for campus cultivation. I was very proud about that team and all that coming together. That's so cool, dude. Yeah, I'm also working on a book still. I'm still trying to get all the details down. It's basically meant to be kind of a treatise, or, like a, like, my thoughts and opinions on, like, the theory of pest management and kind of the ecology, not like a framework, like, here's necessarily just what you do for every pest. But also, like, Teach a man a fish, rather than giving the man the fish as a mentality, like, why we do things a certain way, and why maybe we should think about doing things a certain way, from a sustainability, from an ecological, from a efficiency mindset, you know, kind of in in various contexts. So I'm excited about that,
fantastic. So that's a treatise on pests. That's not a treaty treatise, that's not a treaty with pests, because I'd be down with that too, you know, like a ceasefire would be fantastic at this point.
I mean, seriously, and in a way, that's the communication that we're going to talk about with resistance. It's a very, you know, ecological way of talking with them.
That's a good point, man, it is a bit of a communication, or, like a biological alteration when we. Are using something on them, they will respond. The word is, respond, right? Yeah, there's a selection pressure sort of totally. So it's a little bit ways, a little bit of a conversation, a little bit of a dance. It's a dance that's good stuff, dude. Let's dive right into this, man. So listen what I've been dealing with recently. I want to start here before we go deep into powdery mildew. I got a very telltale pest in my garden that I've never dealt with indoors before. I've only seen this pest damage in person, on Molokai, outside, doing outdoor growing. A lot of people confuse the damage of this pest with thrips damage. You know, thrips have that. If I can just describe it through audio, they have that kind of white scratching, not so much the the stipulation, like you said, like the white dots, as you've said on the show before, that spider mites do, but more like little scratches. But this pest that I've dealt was dealing with has similar scratches, but, man, they're like these long lines, as if someone took a white like Crayola or like a light green Crayola crayon, and kind of drew these long lines on my leaves. And if you can imagine what I'm talking about, you've probably seen this before. The damage of leaf miners is what I'm talking about. Audience, the damage from leaf mining insects that that create these tunnels inside the leaf tissue. We're gonna get into all of it and make this telltale damage. Um, Matthew, I've never dealt with this inside. I'm sure you probably see it all the time. But like leaf miners, I consider them a rarer pest. I had some. I think I've dealt with them, knock on wood. But, um, is this something you see in cannabis a lot? Is this something you see indoors a lot?
I
would say that I've heard more people talk about it, but I think that's a sampling bias, possibly from just working with more people and that kind of thing in cannabis. So I wouldn't say that it as a whole is getting bigger, but I don't I would agree with you. It's kind of an incidental pest. I often describe it this way. I have a video on my zenfi YouTube channel that goes over that, and I love it when I can actually describe a pest as being kind of mild. Sure,
that's what I've discovered, Matthew, is that they don't seem to leaf minor progression doesn't seem as bad as like some thrips and some spider mites. They're hard to get rid of. But would you consider them a lower threat than you spotted spider mite? Let's say the like, the quintessential
bad guy, yeah, especially against, like, a lot of the more common ones, yeah, like spider mites, like russet mites, yeah, I would definitely put them at like a maybe, like a one or two. You'd have to be really, I think you'd have to be really neglectful, which it doesn't sound like the people who come to this girl cast channel are generally speaking. So I think that most people with even a basic level of vigilance, get it done Absolutely. I'm
just going to say, for those who are watching, tune into our next YouTube stream. I'll be showing some pictures, and, of course, jump in membership. We're going to talk about it on grow cast TV. But that's the best way I can describe Matthew the damage on the leaves. It literally looks like someone drew these long unbroken lines that now look like white, light green, almost white, I'm assuming, from, like, lack of chlorosis. Um,
what are they doing in there? Yeah. So, so there's two kinds of leaf miners. The ones that I'm most familiar with are flies, leaf winter flies, agro misid And they basically, when the flies deposit an egg into the leaf, into the skin of the leaf, the epidermis, basically, it has a little little blade that it cuts in to make a little incision, and then it deposits the egg, and then that egg turns into a little forearm, little fly maggot, and that maggot, as it eats more and more of the like meso field between the top and the bottom of the leaf, they hollow out a tunnel, and you get these designs that could be spiraling or kind of like, you know, long and different species do it different ways, and that is basically what they're doing. And then, depending on the species, or whatever, they'll pupate inside the tunnel, or they'll come out and then pupate, or maybe fall to the floor. They look like a miniature version, if you've seen like a house fly pupa, some flies like fungus gnats, so you can see the adult body. It's a more primitive version. But flies that we deal with are like house flies, blue flies, that kind of stuff. They have this like shell that looks very similar, but between different groups. It's just kind of like the oblong, sort of featureless shell, mostly. And then that hardens. And then the adults finally pop out, and they mate and complete the cycle. Although, fun fact, the males can't feed without females, because the females make this little blade, this little, little incision, and they drink from the sap to sustain themselves, and males have no way of doing that because they don't have an ovipositor. So Whoa. So
they have to look for the females who cut into the leaf surface and then use their incisions basically. Wow. Okay, this is great, dude. You fucking know so much about, pardon my language, so much about, no, it's fine. These pests. One thing I see is growers confusing this, like I said, for three. Damage, and they're going, I don't see any pests on my leaf surface. Usually, when you've got a thrips infestation, you're seeing damage hang out long enough in your garden, you'll see one of those yellow kind of grain of rice, smaller than a grain of rice, but shaped like a grain of rice, crawling around on your leaves. I think people confuse these types of bores that you're saying for thrips, whose damage sometimes looks similar.
Yeah, I agree. I agree that like the patchiness of like the thrips damage profile can definitely look like this, especially like the first if they've never seen it before, I could see how somebody could mistake it. Yeah, I totally agree with you. Longer
unbroken lines is the only way that I can tell you how to distinguish whereas thrips, if you see that leaf damage, looks like a million little scratches, that's the best way. The best way I can describe it. From audio. So, Matthew, if they're living down in the leaf tissue, this is, this is what I've learned. You tell me more about it. I'd love to hear your your brain activity on this, but I've heard, since they're down in the leaf tissue, you got to kind of send something in there after them, topicals. Quote, topical sprays aren't going to work as well on them because they're protected in leaf tissue. Is that true? Right? And what would you use to destroy them
thoroughly? Yeah, that is definitely true. And there's been a few different kinds of products and like other crops that I played around with, one of my most successful examples early in my career was against leaf butterflies in Gerber daisies, normally not a big pest, but because, for California and we have a bunch of vegetable crops, they would come in a lot, and there weren't a lot of products for it. So we had to get creative. And so I want to say that, like, besides products, some things that you, you know, of course, you consider, is, like, just trying to, you know, if you have, like, insect screen or something like that, if you're outside, you're gonna find them a lot. If you're inside, I would say, like you articulated, not as much so right then and there. That might make your decision. If you're around, you know, a lot of, like, a Leafy, herbaceous like dandelions and things like that, you might also discover a round of property that they are there. So they're
generalists. From what you're saying, I'm hearing that these are generalist pests. I
would say that, like, there's a lot of the species that I'm most familiar with in the USA and a lot of North America. Are they like to go after a lot of different like, yes, basically, like, celery and lettuce is a big one, I think. And there's a lot of like, weedy type plants that have big leaves that they tend to like, go and do well in so I was, I would watch out for that. If you're worried about it, big leaves, they can just kind of go ham in there. Yeah. But to answer your question more exigently, I actually found some research that showed that the combination of bouveria Bassiana with like an adjuvant or some kind of like penetrant, which maybe something like a steel soap, or something like that, could be useful. This is speculative, but like we were looking into using we had other penetrants and things that we had access to for an ornamental and I don't necessarily recommend for cannabis, but I think that the physics of it is similar, because what you need is something that will carry the sporlow, the inoculate into the tunnels, because there's going to be holes, or, like, because there could be micro tears, and so they they kind of seep in there, And they're basically screwed if you get, you know, more than a few 100, which is likely,
so they're not
hard to battle if you're using the right tools. This was my experience. They don't spread super fast, and if you use something that's going to go after them. So, so let's just dig in here. You said the Bavaria Bassiana, which is a bacteria or bacterium
fungus. It's a fungus. Okay. Why does that get
down in there? Are they moving? Are they able to move? Is it just, is it the penetrant that brings it down in there? Yeah,
it's just because of us. Like, if you spray it, it's possible that you'll still get, well, for one thing, if you catch the larvae, and they're like, pre pupil, like, I'm ready to go pupate form when they if they cut out of the leaves, which I have seen in cannabis. So I believe at least if the species I've had are like this, they'll also drop onto the soil or whatever your substrate is. So you might also consider either like as a draft in a pyrethrum or something like that, to hit any that might be outside of the tunnels. But for those who are in the tunnel that you see, and assuming that, and this also assuming that you have a bunch, if you're, like, indoor, and you only have less than 10 plants, or something like that, and you see, if you you could just smash them. I'm a huge fan of, like, just pull the leaf off and look around for them. And also employ things like blue traps, other stuff, so that the leaf miners, a lot of times they're attracted to really bright yellow and glossy. You might even be able to find them in UV traps if you want to set those up. If they can be double up sword for obvious reasons, attracting things, right? But this
is a good example, because they're not always out of their house, is what you're saying. You want to get them when they're out of their house, maybe you put some of that sticky stuff around your stock so when they. Fall out of their house, and then they go to climb back up. They get caught in this thing, stuff like that, right? You're trying to catch them when they're outside. Catch them lacking, yeah, you want
to catch them so that you can know that they're there for one and also, if you're applying a treatment like what we're talking about here, or other strategies, like you said, they don't really grow too far. You can really nip them in the bud, but you want to be sure that you know, because an adult female can lay like 250, 300 eggs, potentially, and the first incision doesn't look I mean, they let they leave these things called stings. We would call them stings in our Lady stinger. But yeah, la Mosca, Pinta, the painted fly, as my co workers would call it, would sting the leaves. And I've also seen this in cannabis, so you actually can see them, unlike some other insects that are more sort of obfuscatory. Whoa. So
might I grab a microscope? Because, because Matthew, I never scoped the leaves, but I have not seen the culprit in my garden. I have seen the damage, and the first thing I did is what you said, which is, well, if he's down in the leaf and he's making this beautiful spiral design, how about I just pull this leaf, he's probably still in it, right? Take it out and absolutely and get rid of it. Take it far, far away. Throw it in the fireplace or whatever. Yes, crush
it. Stomp on it. This was, yeah, we did a hat, dancing around him sometimes, and try to scare the rest of it. Yeah? Make a statement, yeah. You know, write a pop song about it. Send a message, yeah. But you, you got to look for the tunnel. That's how you'll know. There's also a bio control for the leaf miner flies, not the, not the moth larvae, that are also called leaf miners. But I don't, I have never found those in cannabis, so I'm not sure how common those are. Fly ones have been and it's called dilyphus, the bio control is a wasp, but they're very expensive. I think they're like 50 cents a wasp, and you usually buy hundreds at a time. But it's an example I want to bring up, because I know some of your listeners are people who work in industry. I could use the knowledge, and also, in some cases, you might just care that much, like in a fino hunt or whatever. And so these are wasps that parasitize the larvae. But to be honest, I don't think you would need them in most cases. And I think this is very important to know, too, not
a huge preventative, like effective preventative, just by nature, that they might not have anything to battle. I'm saying that leaf miners aren't super common, exactly, exactly, it would be a situation. The only situation I would consider using them is if somehow, some way, it got really away from you. Maybe there's a species that we've never heard about before. Who knows? I like to keep an open mind, because we it's happened before, sure, in other pests, so, but, yeah, generally, generally, not necessary. Okay, that's great, man. Let me tell you what I did with my preventative treatment, actually, my my knock down treatment, I guess, and prevention since then. And then you tell me how well I did it, and tell me how this whole thing works. So I grabbed some nematodes, nematodes, I say nematodes. SpongeBob taught me. So I went to a website and grabbed the ones that specifically said they killed mining and boring flies, like the ones you're saying, Oh, it's SC and SF. Are the two that they recommend, caps, CA, or whatever, I'm
sure cap C or something,
LTA, yep. And then felt TA, which I was familiar with from the triple threat, but they recommend these two, right? I'm like, okay, okay, great. I order them up. What I don't like about them is, you got to use them quick, right? So I went way ham on the dosage. If I open this thing and it's going to be gone in a few days, it's going to be no good after that, because that's how these biologicals work, is my understanding. Please correct me if I'm wrong. I just said, Fuck it. And I took a big old scoop. I put it in my one liter bottle, I sprayed all the foliage, I sprayed all the soil, and then I did it again the next day, because I figured that they would be, you know, the nematodes would be dead soon. And then I let them do their work. That seems to really do a number. That powder goes everywhere. I don't like spraying it, but they started praying instantly. I think some of them were affected, and I see, I saw the damage cease. Once I gave the toad some time to work, I followed up some spinosad, thinking, you know, spinosad kills some like grub, like things. It's a bacteria. Maybe it'll, you know, wiggle around and get in there after them. But it seemed to work effectively for me. And the reason I went with toads is because I was told that toads can actually move. They will get down into those tunnels and seek and destroy them. That's what I was told. I seem to have observed it worked in my case. Knock on wood. What do you think about using nematodes versus flies? And any tips or tricks for applying them? Because they're quite tricky for the leaf miners. Oh, what'd I say for flies? I'm stone for leaf miners. Thank you,
Matthew. Oh, just Yeah, that's what she used them for, right? Just wanted to 100% this
was the same plan where I saw that long line, I got rid of the leaves, and then I blasted them with some Toad powder and some spinosad.
So it's interesting to bring that up, because I seem to remember that when we were looking up for some novel strategies. We did come across examples of, if you can believe it or not, you sprayed these on the foliar, right?
I did, yeah, it makes your plants look like shit, but it works, yeah? Because actually,
although these nematodes are not from there, and so it would kind of, in some ways, not make sense ecologically, but it works out because you're spraying like hundreds of 1000s, or really millions, ostensibly, that's usually the packet size, and then there's holes, right? And so, like, even if point, oh, 1% find their way into the tunnels and through, like, the meniscus of the liquid, right? You know, getting into the tunnels, and now they're slithering through on a microcosm, they just got to enter into the orifices. This is a very like atypical, abnormal encounter for the leaf minor larva. So it kind of makes sense that they're super susceptible to it.
So if an if one of these toads gets at one of these things, they're effed like it's a bad matchup fight wise. And what do the nematodes do? My understanding is that they're not technically predatory. Is it true that they kind of get up in the bugs and eat the bacteria and their brains and crap?
This is an ecological technicality, right? So, like parasite and mutualists and these kinds of terms and their ecological terms, and so if we want to be technical, the nematodes, like you said, they have a bacteria inside them, and it's what they release to kill the host. Oh, and yeah, so it's a poison kind of, it's a bio weapon, right? Yeah, wow.
I always thought that it was like something that they were kind of eating or destroying, but it's literally the nematodes have some bacteria or some fucked up stuff inside them, and then they get at these guys, and the leaf miner doesn't know how to deal with that. And
then through that, yeah, they do. They do colonize the hose. They do eat the material, and then they produce a bunch of basically reproductives, and then they kind of just filter away. That's why nematodes, like, just for those who don't know, you know, you kind of get to use them. They don't stay persistent in the soil. Like, you can't think, like, oh, I put nematodes out a year ago, and those nematodes are still out there. Like, if they did their job really successfully, it's possible that they die out with the host, and if there's no other viable hosts, and so that's a thing to consider. And they also won't, like, travel up in your plants. You got to, like, have them make contact. So that was, that's, that's a really brilliant move, and this research that shows the people that this is, this can be effective under some circumstance. Wow, great
stuff. Yeah. Mary Beth was the one who suggested it, and I had your exact thought process, which is, these things aren't going to stay alive. I'm going to spray them. They're going to wake up, and then I don't know. How long do you think this might be a tough question. How long do you think they would have if they were just sprayed onto the foliage and they're they're running around looking for anything to eat, like you said, hopefully just a portion of them get down into the tunnels. But like, How soon after that might I spray with something like spin a sad where I know that the toads have probably done their work, so I'm not hurting them, but I'd kill anything else that was left over. Does that make sense? It
does. If it were me, I think that I would concentrate on, well, for one, if I could spray like, assuming that we don't have the leaves the light on. Two, that's going to really help a lot, because the main factor is that they're going to desiccate. The surface of the leaf is actually pretty hostile on the micro scale, or at least it can be. And nematodes aren't meant to be on there anyways. So anything that you can do to reduce desiccation is really important. If you're one of those people who does have, or is making use of UV light, that's going to be much more lethal to the nematode. So I'm thinking like if we have scenario or outdoor,
ooh, or if they have those supplementals now, or they have the supplemental lights, right? Exactly. Holy, exactly. Great. So definitely spray them with the lights. I hear they're finicky. Matthew, I hear you're not supposed to leave them in the solution too long. You got to keep it stirring, because they'll drown agitated. Yeah, they're not cheap. It was $60 for these two packages that I didn't even really get to use all of before. I figured they were kind of dried out. So, yeah, like you said, it's not necessarily, like super applicable to everybody, but I will testify to its efficacy. I'm knocking on wood, but I have not seen any new damage since applying two heavy sprays, two days in a row, of the toads, and then I think I waited a day or two just in case, and then started spraying. Spin aside, I
think that's awesome. Honestly, I like to see these examples get sort of murder boarded, yeah,
unscientifically
trialed, yeah. I mean, you gotta start somewhere. And honestly, like, it's not very common, so it's even more important to see this kind of get used. So I appreciate that. Oh,
I loved how you described what they do, and the males and the females. And are there any other thoughts on mining insects, how they behave, how to control them, or anything, before we move on to the meat of the program?
I think that. I just want to reiterate that it's one of those examples where, like, prevention is so useful for getting rid of something like this and even having like, you know, insect trap or something like that. That you can tell, even if you leave it in there longer than you should, you can see if something comes into like your your house or near your tent. It's just good to have that kind of info lying around and checking that regularly.
Good call. Add some sticky traps and really, to help identify it, right? Because at the end of the day, you can go off of damage. But like, like you said, there could be a whole new species that you're dealing with, or subspecies, you know. So listen, man, this is great. I got a right? I did get that from a cutting that's how I got that leaf miner. I know, I'm almost certain that's where it came from. So quarantine and prevention absolutely key, as is for the next subject that we're going to talk about, you know, powdery mildew. I feel like this is one of those things. Yes, it can also come in on a cut, but it's also one of those things where, like, if you've got your airflow on point, you've got air circulation, you've got ventilation, you keep your humidity down, you de leaf, a lot of fan leaves. You can really mitigate the risk of powdery mildew. I feel but you tell me, how do you feel about powdery mildew? Where does it land on threat scale, and what have you been learning about
it? I feel like, for a lot of people, powdery mildew is really high threat. I'm biased because of the like, the professional nature and the scale that sometimes that lends itself to, and perhaps even like the sort of austere conditions of the personnel that are able to check for it. But because it can spread so much, I put it, I put it on average, like mid can be higher, but I do think it's mitigatable, especially if you have prevention procedures in place, like looking for the colony, not letting it, like build up really aggressively, was really paramount, and then also understanding things that are actually relevant to its growth. I feel like a lot of people feel that powdery mildew is, like a humidity problem, and they also sometimes confuse that it's a systemic issue. And I would challenge those twos humid start with
start with humidity. Because my thought is, hey, if you don't want molds, mildews and fun guys, you don't want, like, 60% above humidity. Is this not the case when it comes to pm, does it light? It dry?
It's more like I would say that I don't, I just don't want to engage in what could be like biosecurity Theater, where, although it'll have an effect, I don't know that it will have an effect. That sort of washes out the fact that it might already be there, so it's
gonna be able to take hold at these lower conditions. Yes, it might help. But, like, You're not safe just because you're at 40% Rh is that what you're saying?
100% I just want people to use, like, really assured procedures, sure. And also I know that it does well in dry conditions too. Famously in the mycology world, it was found very early that powdery mildews contain a lot of water in their spores compared to other fungi, so they actually are packing some supplies. Wow.
So if they need to get on a desert plant, they'll have a little bit more hydration, a little bit yeah, that makes sense. Man, you're right. So let's put it this way, things like air circulation to stop those spores from landing or taking hold, probably much more effective than just going, Oh, my humidity is low. I won't worry about pm, you like option one? Much better than option two, right? Yeah,
I think that. I think it's more like controlling the air flow in that you're controlling what's going into your into your space. That's the most important aspect of the airflow that you have. Airflow, I think is less important, maybe is helpful for other things, but it's more like, does this are there sport, is there enough spores? If there's 1000 spores outside of your house, let's say, and then, because of the fact that you have a door and screen all this stuff, you know, they go through and that cuts out, like most of them. Now, you have 100 spores, right, hypothetically, nominally, coming into your room. And then, if you want, if you can take 100 to 10, you know, if you can decimate that, that level again, one less magnitude, then the chances that those spores even will be tenable, not does themselves land on the leaf itself in the right place and not like on the walls of your grow you know, is less and less. Does that make sense? So I think it's a numbers game. Is
that why you might be a fan of like a filter on your intake where maybe they make it through your front door, maybe they make it into your basement, but as soon as they get sucked towards your grow tent, a lot of people have a filter on their intake fan for this kind of thing,
exactly. Yeah. That's why I think something like that is so vital. All right, dude, see, this is changing the
way that that I think about it. The grand fino hunt Round two is on. That's right. Members are hunting through their own genetics, trying to find a unicorn, and one lucky member is gonna win $1,000 in exchange for the winter cut you can get in on it. Now, all you gotta do is be a grow cast member. Heck, you can sign up for like a buck 50 using code river go to grow cast.com/hunt, to find out more about the grand final hunt, you can jump in as you hear this, and pop seeds and get in on it. If you're growing anyways, you might as well be part of the Grow cast. Grand Final hunt. You might win 1000 bucks, plus a lot. Of side prizes again, grow cast.com/hunt, for more info. And there's so much going on in Grow cast membership, other than just the hunt. You're gonna meet a bunch of grow mes. People are trading every day in the trading bazaar. We have weekly live streams. We have discount codes deeper than anyone else can get, like 35% off SD microbes and 20% off hlG, lighting and so much more. It's all waiting for you at grow cast.com and check out the hunt. This is an interesting one. It's a battle royale. People are popping their own genetics, and someone's gonna win 1000 bucks. We make growing fun and easy the way it should be. Check it out@growcast.com you have until March 1 to get your seeds wet. Join up today. Grow cast.com/hunt, and of course, grow cast.com/membership, I will see you on the inside. It's going to be the best move you ever made as a cultivator. I guarantee it. See you there, everybody, and best of luck in the hunt. I want to go back to something you said, which is so true, especially on a commercial scale, powdery mildew I've seen spread crazy fast. Matthew, like overnight. It's a disaster. I've seen insects do spread quickly and do similar things, but it seems to me like powdery mildew, if it wants to, if it can, if it takes hold, one of the fastest spreading pests, correct? Would you say that?
I feel it's really true. And so like over and you can smell it. I don't know if you I've heard this. You know what it smells like? I definitely, well, it's mildew. It smells like other, like, mildewy fungi and on other crops too. It's a very similar sort of farenaceous. Is like a wet towel, like a musky, yes, it's like, mealy. It's like, it's like, the smell of, like a grain that is, like, left out a little bit, you can kind of smell it. Start to get that's
a good description to start you. I've heard this. I've heard people say they can smell powdery mildew, and say, I'll walk into someone's room and I'll smell it, and I'm like, Whoa. You know, I've shown a family who's like, that. He's a human mold detector. He can just, he's really sensitive to it. And, you know, we walk into a house for sale, and he will literally be like, there's mold in here somewhere. I can, I can goddamn smell it, like you said. So that's very interesting. That's
more impressive than me. Honestly, I think that's a that's a real superpower. Yeah,
right. It's a give and a take. But, um, I do see it. It's one of those pests that I feel like it's just around. It's around. People get it on their clones when they order a clone. A lot of people call it systemic, like you mentioned, and I know they have a the reason they call it that Matthew is because they have a real hard time battling it. They tend to treat it until it appears like it's completely gone, and then seemingly, quote, out of nowhere, it kind of reappears. Can you talk about how Pm is technically not systemic, but can still be persistent.
Absolutely. Put it
correctly, it's just a factor of not knowing its biology, which is totally super normal. Most people aren't spending inordinate hours on this, like me, but it's totally valid, because a lot of other pathogens have this kind of like syndrome. You know, you see it on one leaf, you see another leaf. It makes sense to think that it might have traveled. So it's totally makes sense. But what's actually happening is even, like a
backup spore hits your plant, maybe
first 120 hours, is invisible. It's colonization. This, this battle where you know, dozens of plant cells either succumb or don't, depending on the robustness of the plant, resistance to the powder mildews invasion. Assuming that's successful, eventually you'll see a colony, and you'll have, I mean, by the time you even see like a small like one or two, like millimeter patch, that's like 1000s of 1000s of 1000s of spores being produced. That's what all that white powder is. It's the coviddifors, which are long chains of spores, and they're going to be infecting, you know, the spores, they do not they move on the air currents. So in some ways, air flow could be a bane, but a lot of times they don't move very far, but that means that they can easily hit other parts of the plant. So you're getting re infection cycles. And that's what is so alarming, and why you'll see these populations grow and grow and grow.
So
when someone thinks that it's gone, and it quote, comes back from, you know, seemingly within the plant, do you propose that it is, in fact, the same infection that has just repopulated again, like you said, and maybe those spores are still establishing and sporulating, you said, 120 hours, that's five days. Is it just that they, it's still there, and they can't see it? Is that? Is that kind of what it is? I think so.
I think it's really, this is where, like, it's a, it's sort of a doctrinal question, you know, I don't I need to have more context to find out what exactly is happening. But I think it might, in my experience, what typically is the case is that they say spot treated, and by that time the sport is, like you said, kind of went around and, you know, they didn't actually try. Be everything. So that's one vote for treating your entire crop instead of just one if you see it, because it's worth it. For that reason. Also important to note that it's not like other molds where they can, like grow on, like drywall or like wood or things like that. It needs a living plant host. It could be that there's plants nearby, on or around your property. It's pretty much impossible to tell the visual and our understanding of powdery mildews and cannabis is not really sophisticated, but you know, that's another factor to consider too. So
I've heard that powdery mildew can spread from one plant to another, but sometimes it doesn't like to what if you do have plants outside that have powdery mildew? Can that jump right onto your cannabis? Or is it more complicated than that? Yeah,
there's definitely. There's only a few species that we know of currently, like golivina myce is secret serum is one, which is called lettuce powdery mildew. And then there's also golivinas Ambrosia, which I like to call the immortal powder mildew, because that's with the species name I'm bruising. Oh God,
what a terrible name. It's a terrible
name, right? I'm trying to be literal. I was like, I want to be literal, but it's literally immortal. Like, come on, whether you're looking
up what you're you're looking up what is messing up your grow tent and killing your plants. And you Google the official name, and you see that it's called the immortal powdery mildew. That's literally the last thing you want to read.
I just hope I'm not a trendsetter. Yeah, it's just that's hilarious. Yeah? I mean, you know, it sounds like a Elder Scrolls character, totally. You
cannot kill. PM,
but to this place of destiny, why have you come unprepared? Yeah,
exactly. Good call,
yeah, good call, yeah. So here's the thing, and we're going
to talk about resistance a bit this kind of folds into it. So powdery mildew ecology is interesting. Long story short is I believe that the species that colonize cannabis, the golden mice ones. This is the genus name. There's many host plants in this genus, and there's many different species. Most powdery mildews colonize a few different plants they're specialized on. But there's a few species that are huge generalists, and so go live in a Mycenae. Secret serum is one of them, 300 plus hosts.
Oof. So let me ask you this, man, I know this is a general question. You're probably not going to like the late is it more likely then that our cannabis might have powdery mildew that hops to another crop, like lettuce, as opposed to our lettuce having powdery mildew that hops to our
cannabis? It's a good question.
One of the other, one of the things, is that, like cannabis and lettuce, for example, are very different plants. So ostensibly, the traits that you would need would be very different, and so a species that can accommodate the one and the other, if populations start to develop a lot on cannabis, it might also lead to other novel traits that could maybe shut down the defenses in other plants, like lettuce, more succinctly, more in more capable ways, simply because they got to do a little bit of, you know, tournament, you know, travel. Basically, we got some experience. They
got some experience. You think that they have experience points and they leveled up. Yeah, I want to talk about this, because what you're saying is that the that the powdery mildew essentially learns it goes back to what we were saying about this conversation that we have as pest and one who battles pest, and you said novel traits developing that sounds like evolution to this this lay person. How fast can powdery mildew mutate or evolve or develop novel, new traits, some
of the research in other species that are not cannabis ones, most species knowledge we have is in wheat and barley and grains has shown that some really powerful and potent fungicidal resistance and even hybridization events can establish
within get this like months. She and weeks. They
found that some colonies that were in some lab reference colonies that they use when they do research, that they kind of keep over and over on the same host and the same conditions, you know, they found that the the colonies just mutates so much that you get this sort of mosaic of traits really easily. Wow. Yeah, so it's actually kind of scary to think about it that way, yeah, but yeah, that does seem to be the case. And we've also seen seasonal resistances of things like Eagle 20, my faubutanil in like wheat and stuff and similar sorts of chemistries in one or two seasons, wow, across like the region of Europe or the USA, or something like that. So it can happen rapidly. That
is so fascinating, man like we think we're such hot. As humans on this planet, because we call ourselves a dominant species, and we have language, and we can use all these big, fancy words. But when it comes to the end of the day, when we're trying to grow some plants and this, this mildew, gets on there, we hit it with the most toxic nuclear stuff we can. And this mildew, in a way, outsmarts us, mutates, adapts, develops new traits, hybridizes like you said, effortlessly in a matter of weeks. That is wild. It seems like powdery mildew is smarter than we give it credit for. If I can personify the white substance for a second,
agriculture is actually a big reason why, because it's been shown that, like in wheat, powdery mildews, when humans would concentrate the wheat in an area like a field, then that created the conditions for sort of potent, regular, reliable, sort of adaptive flow within powdery mildews. And so nowadays, they also travel with our crops, and much more faster through trade and that kind of thing too. It's a problem that we caused ourselves. And actually, when humans developed bread wheat, basically right around the same time, a new powder mildew hybrid came about 10,000 or so years ago, early agriculture, we still are dealing with the same powdery mildew. It didn't go away, and fungi could be some of the oldest form of life, right? So did this thing wait for us for millions of years, and then we started agriculture, and it's like Game on. Well, here's where it gets even more interesting, powdery mildews based on their phylogeny, so their relationship to other lineages of fungi, they seem to have a lot of traits that are similar, like mycorrhizae, and their closest relatives are soil fungi that are known to be saprophytic, so they break down like dead plant material, like cellulose. They have the same genes, orthologous genes, so that means that they came from the same common ancestor. And that implies also, because powdery mildew fuses with plant cells when it, when it colonizes the leave cells or the, yeah, the membrane, they have this intimate connection. It's possible that powdery mildew was like a good guy that went rogue. No, we used
to be, like, a beneficial type fungi, or
maybe even just kind of common cell, like, like beneficial in that it broke down. Yeah, plant tissue, perhaps it was a symbiont that was mutualistic too. Like mycorrhiza are. When you shut off the genes that let them communicate with mycorrhizae plants, you also shut off the powdery mildews ability to colonize. So it's, it's very it's very interesting. There's a lot of circumstantial evidence that seems to point to powdery mildews having been about 100 million years ago. Is when Jesus the first powdery mildew are thought to have developed 100
million year old species. And like you said, it used to just be breaking things down, and then one day, it's like, you know what? I'm gonna attack all these crops these apes are growing, and I'm gonna, it's a good way to proliferate, like you said. And then we start to colonize the planet and ship these spores all over the planet. Hey, I'll, I'll send you a cut. So you're, you're sending the spore across the planet to your buddy. And powdery mildew says 100% thank you for your service. You know what I'm saying exactly
well, and there's actually a lot a lot of like wind flow from North America, from from, I guess you could say Russia and eastern Asia across the Pacific into western North America. And so that happens a lot, both ways. And yeah, we make it easier even than that.
But wow, spores travel across the Bering Strait. I mean, that makes sense, right? You can see the other side. That's right from your house, if you're in Alaska. Yeah, that's scary. Now you're starting to freak me out. That's really wild, man. It seems like this is one of the smartest again, if I'm going to personify it seems like one of the smartest, most insidious, most fast spreading pests. Maybe not, as you know, maybe sometimes you've dealt with powdery mildew, and it wasn't quite so devastating in your case, but it certainly can be listener, and it just has these really interesting innate abilities and adaptations. Man, very fascinating. Matthew,
I think that the key to dealing with these, like hyper adaptive pests, is that you gotta, you gotta have, like, a multi dimensional approach to things. I also think that it teaches us because of, like, their ability to and here's another unfortunate thing, is that when other pests, like some insects and things, if they develop resistances to, like, really noxious chemicals. It's usually at a detriment. Usually the thing that allows it to live well is that it's, like, got 100 times resistance to, like, something really crappy. But usually there's a downside, like they move less, or there's a neurological thing, or. Ever powder visitors do not have this. Whoa, crazy, seemingly, seemingly, the research doesn't seem to show much of a like, a downside for like chemical toxin resistances, at least. But that being said, for those people who are like, using things they shouldn't use your time is numbered, like those chemicals you said before exactly, you know, like, you shouldn't be using them anyways. And usually I feel like another besides the ambivalence that you might have towards, you know, whoever gets your stuff, which I don't condone, but it's also often done as an economic reason too. Like, I just have to, like, spray this one time, and I'm and I'm good for a long time. Woof. I feel like this just teaches us that it's brittle and fragile to create too lean of a system, and you need to have multiple components that often does mean some redundancy, or does mean that maybe it's a little bit more expensive in some ways, to have the options available to, like, go at it in a multiple way, but it's also way more robust. And I think you save out on the long term by having, like, a smart strategy in how you approach it. Well,
you know, it's all well and good until you lose an entire run to powdery mildew. Like, of course, your lean system is great because it's costing you no money until disaster strikes. So you're right. People can feel like, Oh, this is redundant using these different products or spraying so many times, but it's like, No man, you're hoping that you don't get invaded by the Horde, essentially.
Yeah? And I think there's a way to, like hedge it to be, like, efficient and and smart about it. I think a big part of it's like the crop scouting, right? Like, maybe you don't have to apply something to powder mildew every week that might really eat into it. But if you wait until, like, you know, you get it every winter time, and so you start during the end of autumn, and you save yourself a bunch of money, right? Yeah,
I like that and, and also different modes of action, right? Because, like, Okay, let's go back to what you said, you know, micro butanyl and Eagle 20 and all these nasty chemicals, man, in my Bracken mind, Jay, horticultural oils are just, they're great. You know, they're strong. They kill pests. My understanding is they kill powdery mildew as well. I want to confirm that before I go on this whole tire tribe. Matthew, do do? Oils kill powdery mildew? There are
definitely some that do, yeah, absolutely, because they they either have compounds that are detrimental, and they're basically fungicidal. They kill the spore. The spore is actually very weak. An individual spore is very, very, very weak. And so the oil just being there suffocates and, you know, poisons the spore, which has very little defenses to that much product. That's essentially what you're doing. It's a really good one two punch in one, yeah,
I can imagine that, like the suffocation effect probably has some effect. And I imagine that would be harder to adapt your way out of than just like a toxin, if you know what I mean exactly.
It's like two really problematic things coming at you. And that's why, you know, although I don't there, there are ups and downs using horticultural oils. But, like, that's why I think that people shouldn't be afraid of the idea that you can have, like, the multi domain approach. It could still be cheap and it could still be easy to apply, like, for example, in that, in that, right there.
Yeah, good stuff. I do want to say, Geez, this episode flew by. We're going to wrap in a second, but I do want to say something about fragile spores and spraying microbes, and also go back to the the nematode talk, because I feel like I'd be doing a disservice, Matthew, if I didn't talk about this when I when I talk about spraying toads, I use a a hand pump sprayer that's literally just a tube. I've been told not to use things like atomizers or impeller type pumps that spray. And the reason people say not to use biologicals with those is because, supposedly it can destroy those fragile spores. If you're spraying fungi, it can kill the fragile nematodes. If you're spraying nematodes, is that true? How do you feel about like sprayers and spraying microbes?
I do believe that is the case, at least for the nematodes. I think for the microbes, it might be more on a case by case. I think it depends on a few things. But like, Yeah, I mean, I have several I've encountered more than once where people were using, like, pistol sprayers or like a spray wand, and it has, like, a little grading, and it just, you know, you're like, the nematodes didn't work. And it's like because you Swiss cheese them through the grating.
Unfortunately, yeah, so I did want to say that, you know, spraying mindfully, not the same as atomizing with, you know, your favorite toxin or your favorite spray, but definitely an interesting application, for sure. And yeah, there's just a whole magical, microscopic world that we're all kind of figuring out together here, using it in our soil, using it to battle pests, all sorts of interesting things. All right, Matthew, what else any final thoughts on powdery mildew before we do plugs and wrap the show?
Well, you mentioned microbes. There are microbes you can use. There's some stripped of myce species that are that are popular. They're, you know, potassium bicarbonate is a really popular, really cheap product that people like, I like to recommend wettable sulfur to is like, maybe the king for a lot of people, there tends to be two groups of people when it comes to powder mildew, the groups of people who are like, at it early and are vigilant. And for them, powdered mildew is no thing, and I'm glad, and that's really the attitude to have. I think that it can be a very mild threat. The problem is that if it gets away from you, it's a huge issue. So that's why it bumps up a few rungs. You know what I'm talking about. So yeah,
gets away from you quick, man, and I see people. Here's what I'll say at the end. Matthew, be sure to tune into Grow cast, YouTube and the GC TVs with Matthew, so we can show you the visual element of these types of things. And I know most you know, know what powdery mildew looks like, but Matthew, some people don't, and they will post pictures of their I literally just saw this happen again. They will post pictures of their garden, where clearly a powdery mildew outbreak has gotten out of control, and they don't know. They're literally, they're posting pictures of it, and then they get roasted in the comments. Oh yeah, they're powdery mildew weed. And it's like, man, it's just really important to figure out what these things look like and be able to identify them and be able to spot them. Uh, Matthew, maybe we can do a member show soon where we go over some pictures, not of, not just powdery mildew, but like different stuff, because being able to identify it. I think, like you said, getting out there, crop scouting, that's the most important thing. At the end of the day, it really is.
The farmer shadow is the most nutritious input. I think
absolutely,
it's also easy to forget that people don't know things, especially when you've been doing this for like, 15 years almost. So I love to go down to the basics. And I think it's really it's really it's really important, especially for the message that I love to support of yours, which is to overgrow. So you can't overgrow if you don't have a strong immune system, which is more or less communicating with each other, exactly. Man, I mean, there are a lot of enemies to overgrow, and powdery mildew is technically one of them. It is up on the most wanted list for sure. So listen, this was a great episode. Matthew as usual, of course, zentenol on YouTube at sync, angel on Instagram. That's S, Y, n, C, H, Angel, A, N, G, E, L, all one word. Sentinel consulting.com right? Where can people find you? Yeah, sentinel.com, you can also find me on my YouTube, like you said, and I also, I also have sync angel on Twitter, or x or whatever as well. And yeah, reach out. You can also find me on Patreon too. You can join my Discord if you'd like to, if you'd like to, or as little as $1 or as little as $1 Yeah, exactly. I like to make it. I like to make it really accessible. I think it's super important, just like with Jordan here, you know, it's really important to get the information out to people. And, you know, hey, we may have a pest of blues coming out too, coming up, seeing how things, oh yeah, go.
I always love doing those, man. We'll, we'll shoot for one of those later this year, and we'll get people out there. It's, it's such a fun time having the pest Fest on the regular. And, yeah, I just appreciate you, dude. I appreciate you educating. You're killing it out there. The bug education. You're you're really doing a good job. Any updates on the book? I know it's like a slog finishing that sort of thing. Yeah, the update is that, like, I I quit, just kidding.
I feel like it's, I always want to add more. It's scope creep. My update is, I'm reorganizing, because the pace of knowledge and technology, if we want to end on like a really hopeful thing is it's really fascinating. Technology doesn't solve all of our problems. Understanding the problem doesn't solve our problems. It's really either it's a collection of that and what we want to do as a society, but I'm excited enough that it's actually causing me to change parts of my book and kind of future proofing it. So I think that's a really cool feeling, honestly, actually, that I would prefer it over stagnation.
So technology is advancing so fast that you're having to go back and change things in your book, as I'm sure this sort of thing is going to enter the ag sector, all the AI super computers, artificial and, you know, all this stuff is gonna, I just said artificial intelligence twice, but all this stuff is gonna gonna enter the ag sector eventually. So interesting stuff, man, yeah,
it really has been eye opening. And even if things are on the bleeding edge, you know, it's it's what I love about it is not that it's going to be expensive and difficult and all encompassing. I love that there's things out there for the average person, things that have been expensive for a long time are not and it lets us do what we want to do. So I'm a supporter of that. So thank you for being a supporter of other people and their grows and on festa palooza. Man, yeah, I meet a lot of really cool people. So I really love the people that I meet through that as well.
They've been fantastic. Stay tuned. Everybody you know what to do. Go and give a follow. This episode was great. You're gonna wanna stay up to date with Matthew on everything he's doing. On the pest of paloozas, all that stuff at sync angel on Instagram, also on X Twitter, zitter. Give him a follow. And Patreon, patreon.com/sentinel, all right, dude, I'd listen. We're at the top of the hour. This thing flew by. I hope we can hang out soon, in person, smoke one together. You know, that'd be fantastic. Maybe I can get out there. And until then, Matthew, thank you for all you do. Thank you as well. I really look forward to mutual success, damn right. And down with powdery mildew, everybody. That's all for today. Love all you listeners. Special. Thank you to the members. Get in membership everybody with the grand final hunt is on. If you're hearing this now, you can come join. I'd love to see you. Growcast.com is where it all is, until next time. This is Jordan River and Matthew gates signing off, saying, Be safe out there, everybody, and never grow along. Bye, bye. That's our show. Thank you so much for tuning in, everybody. Thank you to Matthew gates and thank you, dear listener and all the members. We're kicking off the grand final hunt. It's on right now. People are popping seeds as I'm recording this, and you have until March 1 to get your butt into membership and drop some seeds into water. We are all hunting through our own genetics, and we are gonna find a winning keeper. Cut, whichever one rich likes the most. Of course, riser rich, the head breeder at grow, cast, Eco, he's gonna pick a winner. We're gonna give away 1000 bucks. We already did this once. Shout out to Sherm, the reigning champion. He's a guy from Minnesota, up north, and he took down 1000 bucks for his peach Smash. Fino for the first grand final hunt. We're doing it again. Folks don't miss out. We got a ton of prizes, lots of good camaraderie and good vibes. Growcast.com/hunt. Jump On In. You got till March 1 if you're hearing this, to jump on in. And even if it's after that, come join the greatest community in cannabis. Stop growing alone. Would you it's time, everybody. It's time. One quick shout out to root relief, nutrients. Rooted leaf.com. Code cast, always the no pH carbon based nutrients, and thank you to hygrosign for sponsoring this hunt. Huge. Thank you to hygrosign. We'll have more on that coming up shortly. So stay tuned. Love you all. Be safe out there. Never grow alone. I'll see you on the inside of membership, and I just appreciate you tuning into this show, so I'll see you on the next episode as well. Bye, bye. Everyone. Be safe. You.
For those people who are like using things they shouldn't use, your time is numbered. You.
