Orchard People

According to Entomologist Thomas M. Dykstra, Ph.D. of Dykstra Laboratories in Gainesville, Florida, insect pests can't attack healthy plants. Learn more and ask your questions in this live radio show.

Show Notes

According to Entomologist Thomas M. Dykstra, Ph.D. of Dykstra Laboratories in Gainesville, Florida, insect pests can't attack healthy plants. Learn more and ask your questions in this live radio show.

In the show, Thomas mentions that anyone can measure leaf brix with two tools: 
Thomas also mentions a PDF Leaf Brix Chart. Here are two versions of it to download:
Leaf Brix Chart
Leaf Brix Chart with Insect Groups

The prize for today's show was a copy of Joe Lampl's new book:
The Vegetable Gardening Book: Your complete guide to growing an edible organic garden from seed to harvest

The host of The Urban Forestry Radio Show and Podcast is Susan Poizner of the fruit tree care education website www.orchardpeople.com.  Tune into The Urban Forestry Radio Show LIVE by going to RealityRadio101.com on the last Tuesday of every month at 1.00 pm Eastern Time.

Learn to grow organic fruit trees successfully. Sign up for OrchardPeople.com's premium online courses at https://learn.orchardpeople.com/

These show notes may contain affiliate links to products. We may receive a small commission for purchases made through these links at no cost to you. Thanks for your support!

What is Orchard People?

Learn how to grow and care for fruit trees with fruit tree care educator Susan Poizner of OrchardPeople.com. Discover how to create permaculture plantings, food forests, and forest gardens in both urban and rural settings. Meet experts on all aspects of comprehensive fruit tree care, including pruning, pest and disease prevention, fruit tree grafting and budding, and soil management.

Show host Susan Poizner, creator of the fruit tree education website OrchardPeople.com, is an award-winning author of three fruit tree care books and an ISA Certified Arborist. This podcast is the winner of the 2021 GardenComm Silver Award of Achievement for Broadcast Media: Radio Program Overall. Learn more and access archived episodes at https://podcast.orchardpeople.com/.

Learn more about Susan's books and courses at https://learn.orchardpeople.com/books.

Welcome to the Urban Forestry Radio Show here on Reality Radio 1 0 1. In this radio show and podcast, we learn about fruit trees, permaculture, arborculture, and so much more. So if you love trees and especially fruit trees, or if you're interested in living a more sustainable life, then this is the place for you.
I'm your host, Susan Poizner of the Fruit Tree Care training website, orchard people.com. Thanks for tuning in. And enjoy the show.
Welcome to the Urban Forestry Radio Show with your host Susan . To contact Susan Live right now, send her an email in studio101@gmail.com,
and now right to your host of the Urban Forestry Radio Show, Susan .
If you've ever grown a fruit tree, you know that fruit tree pests can be a real problem. They can attack the bark, the branches or the foliage. They can eat plant tissue and weaken your tree. Or they might infe the fruit, leaving behind a maggoty mess that you would just not want to eat.
And there are lots of companies that would love to sell you pesticides that will help you kill those nasty pests. But the real question is maybe. Why are those pests attracted to your fruit trees in the first place? And how can we nurture our trees so that they naturally become pest resistant? My guest on the show today is an entomologist and a regenerative agricultural consultant, and he says that fruit tree pests are only attracted to unhealthy trees.
His name is Thomas Dykstra of Dykstra Labs in Gainesville, Florida. And I'll chat with Thomas in just a minute. But first, I would love to hear from you. If you are listening to the show Live today, send us an email and we will enter you into today's contest to win a brand new book. It's called The Vegetable Gardening Book by Joe Lampel, essential Guidance for Growing Vegetables like a Pro, and the book is valued at 24 95.
So to enter today's contest, just send us an email right now with your question or comment, or just to say hi. Send your email to intu101@gmail.com. That's in studio101@gmail.com. And do remember to include your first name and where you're writing from. I look forward to hearing from you.
So now Thomas, welcome to the show today.
Thank you Susan. It's a pleasure to be on this. I'm ready for your questions. I'm looking forward to this and and I guess we've got an hour in order to create as much damage as possible oh boy. I'm ready to give you a good grilling and
I want to understand, okay, why is it you're an entomologist?
You should know what's going on in the little brains of those little pests. Why do pests attack fruit trees?
Pest attack fruit trees, or really any plant. So they would be categorized together. So it's not just the fruit trees, but obviously this is about fruit trees, but they would be attacking it because they can actually use it as a food source.
And I know that sounds funny, but you and I, for example, would not attack an oak tree. We wouldn't go start gnawing on the bark and start eating the branches or anything like that because we do not. Gain any nutrition from it. So the insect is only gonna attack something that it can gain nutrition from something that it can consume, use as an energy source digest.
And that is the reason why they will attack. So they have various ways in order to detect either taste or smell in order to detect a a fruit tree that is adequate. And it depends of course on the insect, whether it's attacking the leaf, whether it's attacking the fruit or whether or not it's attacking a a different part of the plant, such as the roots as well.
They all have their own little part of the plant for those that attack plants that they go after. And each one is digestible only to certain species. This is why you don't have insects attacking the same part of the plant, and this is why you don't have all pests of a particular plant, such as a fruit tree attacking it.
Simultaneously they all discriminate in their own way. Okay, so why then is it important for us to differentiate what type of digestive system each of these insects have? The digestive system, among most insects at least the ones that are attacking plants, is what you and I might consider to be a simple digestive system.
Simple in the sense that they do not have the complex enzymes that can digest various parts of the plant tissue and therefore they are gonna be rather limited into what they can attack. Digestion is something which is because it's a simple system for them, they need to be able to digest it, and therefore a plant that is already.
Partially digested that is unhealthy, is going to be attractive to them because it is partially digested. It's gonna be much, much easier for them to eat. So they're gonna be interested in going after that, which can be taken into their system and digested. It's the same thing. For example, if if we find ourself in a hospital and they put an IV into our arm, we cannot put a piece of pizza in the iv.
We cannot put a burger in the iv. That's something that cannot be taken into our blood system. But we can take various sugars and amino acids and use that as nutrition in an iv because that's something that's appropriate. It has to be broken down in order for us to be to be transporting it in our blood and for us to take it in our blood.
That's not the case with our mouse and our stomach. Digestion will occur there, and therefore we can assume that. That pizza and that burger that I talked about before. So with the insects, they need to be able to digest it and they will not do so unless it is amenable to the digestive system.
Otherwise, they will literally starve to death. Okay. So I know that insects are categorized partially by their digestive system. There are chewing insects, or for instance, suckin sucking insects. Let's take one of those and look at how they digest and how that limits what kinds of plants they'll attack.
Okay. The limitation the main one that I usually refer to, and it's considered to be among the lowest level of insect digestion are the aphid group. And they have the Only, they only have the ability and in order to suck certain fluids, usually from, let's say, the flown tissue or the XY tissue of the plant where most of the digested nutrients can be found.
So you'll have sometimes monosaccharides and disaccharide sugars in there. You'll sometimes have amino acids in there, and sometimes you'll have some small proteins, something that is easily digestible. The aphid is going after something like that. Its digestive system actually is set up to filter out and pull in those nutrients.
And it's not something that you'll find, for example, among a more advanced insect, like a grasshopper, which can take in a lot of different things and digest them fairly well as far as an insect is concerned. The aphid though, is very limited. And so because of that, you will find them only going after very weak trees very weak fruit trees, whether they're attacking one part of the plant or the other.
That's generally what they do. And that's a limitation in part based upon their digestive system. So basically aphids, which you definitely get a lot of them on fruit trees. They want pre-digested food. They're not gonna work too hard to get through the plant tissue of a healthy plant.
They just want those sugars easily available. Am I restating that correctly? Yes. The sugars is actually not what they're going after, but sugars are part of it. So a lot of the sugars that come in they do e every organism and every insect is going to need sugar. That's really our main energy source and they will also be consuming a little bit of that sugar.
But most of the sugar comes out of the end of an aphid and that is known as honey. Do. And if you have ever maybe gone into the, I don't know, the dentist office for a couple hours and you happen to park your car underneath the tree and you come out and your car is all sticky and you think to yourself, how did this happen?
And that just means that you parked it under a tree that is being attacked by specifically hamus insects, including aphids and others. And they are taking the sugary fluid, passing it out their backend. And so they've got some very sweet poop coming out the backend. And this is how they work mostly.
They're going after a lot of the nitrogenous compounds, some of the proteins that are in there. They're in very low amounts, but they're pretty good at filtering out. And that is their job. That is their job. Okay, so we got a quick email here from Stephanie from Kansas City. Stephanie says, hello.
Please enter me for the drawing of Joe Lamp's book. Love your show. Thank you, Stephanie. That's great. And I think we have another quick email here. Another hello from Ray. Okay, this is from Ray from Detroit, Michigan. Hello, Susan. Just writing in to say hello, as I am an avid listener. Is your guest from Gator Country?
Ooh. Hey, do you have any friendly neighborhood gators in your neighborhood? Yeah, it will not take long in order to find one. All you gotta do is walk out and it's you can find one. Sometimes you get surprised. But we do have gators and a lot of the the waterways. We do have some on near campus the University of Florida which of course is our mascot.
And obviously, I think part of the reason why he's mentioning that. But yes, you can find gators. We have seen live gators walking around. And we have also seen them in the water as you're walking around campus and pretty much in any water whether it be a river or whether it be a lake you can usually find gators.
So yes very common down here. Wow. Wow. So no wonder you're not too worried about fruit tree pasts. You've got bigger issues to be concerned about. Okay, so let's go back to different types of insects and how they will attack the tree. There are also you, so you start off usually when you talk about aphids.
Let's talk about sucking insects. Is there a difference there? There is not as much of a difference. Aphids are sucking insects, and so when I refer to sucking insects in general which I do on some of the charts that are out on the the internet right now, I choose to differentiate because I have noticed over the past couple decades that not all sucking insects are really in the same category.
I think in another two decades I will be able to further differentiate between various sucking insects, but I have noticed that some. Of the sucking insects, specifically what I call the aphid group, which includes scale insects phylos and others that are in that group seem to be going after the lowest level the lowest health plants, that you can find.
And then once you move up to, let's call 'em higher sucking insects, and now I'm talking about the leaf hoppers, the stink bugs the lantern fly which is going on up in the northern part of our country. Those type of sucking insects would be of a slightly higher category, and you will find them attacking higher level plants.
In other words, higher quality plants, not high quality plants, just higher quality plants. The fact that it's being attacked tells us that the plant is not as healthy as it should be. But there are different categories underneath that, and that's when I'm partially differentiating with you right now.
Okay, so let's move on to chewing insects. How are they different? Chewing insects are consuming a lot of food when they chew. For example, if they're chewing a leaf they're gonna be consuming the entire leaf. That will include the epidermal cells, the meso fill cells. They will include the flom, the silent tissue.
It may include the pet, it may include various parts of it. And this is going to be a mishmash and therefore it's not gonna be as concentrated and it's a little bit easier for them to eat. And I have found that chewing insects have a much easier time at going after plants that are not quite healthy, but very close to it.
When you have a sucking insect, they're really going after a very specific part of the plant. And they are only able to handle lower quality plants. And this is again, something that I've observed over the past couple decades. And so that's why I have put together. A chart differentiating the different categories so that we can follow along a little bit better rather than just relying upon some, a few messages here and there on the internet, which are not as descriptive as I would as I would like them to be.
So in the video version of this episode, I'll put it on YouTube and I'm going to include your chart, and it's going to show AFib sucking insects or the higher level sucking insects, chewing insects, and it's going to compare what type of plant it they attack. So tell me a little bit about how you have laid out this chart.
Y it's related to bricks. Can you tell us a little bit about what Bricks is? Sure. Bricks is a measure of the dissolved solids in a given sample of liquid. So it began it is very predominant in the wine industry. The grape industry used them a lot in order to measure the dissolved solids, which generally speaking is the sugar level.
Because most of the dissolved solids in in a citrus tree down here in Florida are gonna be, is gonna be sugar. Most of the dissolved solids in a grape is going to be sugar. And so this is why you'll find on the internet that bricks and sugar are synonymous. And generally speaking, I just speak in them as being synonymous.
If you're gonna split hairs, though, they're not exactly synonymous because there are some other dissolved solids in there. They're a minor component and it's not something that most people worry about, but some people will bring up. So just be aware that it's not a total measurement of sugar.
But predominantly speaking for the purposes of agricultural consultants it really is a measure of sugar. And so the bricks levels is for all practical purposes, a measure of sugar. And taking a look at the bricks levels in a plant is something that gives us an idea of how healthy it is. Why do I say that?
Is because photosynthesis is the process that plants use in order to make food. And the main byproduct, the main product of it is sugar. This is the reason why photosynthesis occurs in plants, and if you have a healthy plant, it will have more sugar. If you have an unhealthy plant, it will have less sugar because it's not photosynthesizing.
In the way that it should be. So taking advantage of that, we now have something to measure and we can measure the bricks and we choose. Most of us in the industry choose to measure leaf bricks as a more accurate measurement. You can test different parts of the plant. I have tested root bricks before and I've certainly tested fruit bricks before as well.
So these all have their their pluses. But as far as the leaf bricks are concerned, this is the most indicative of how the plant is doing because it gives us an idea of how much sugar is moving through the plant and how much sugar is being stored in the plant because a lot of the sugar is stored in the leaves.
And this gives us an idea whether it's a high photosynthesizing plant. Thus hybrids or whether it's a low photosynthesizing plant, therefore low bricks, and this bricks level gives us an idea as to what insect is going to attack it. The internet has not been super clear over the past couple decades because they have always mentioned 12, the magic number of 12 bricks, which corresponds to about 12% sugar.
And they have said in the past that if it's above 12 bricks, you're not gonna get insect damage and anything below 12 bricks you are gonna get insect damage. And it's a very simplistic approach. For the most part it works out and if everyone is comfortable with that, you can choose to go in that direction.
But being the scientist I was interested in knowing a little bit more. And in the process of testing plants, I have noticed that there is more to it. Than just 12 bricks. And that's why the chart that I have starts to break down the different levels, especially as you go below 12, because you just don't find the same insects attacking an 11.4 bricks plant.
As you do attacking a 3.9 bricks plant. And so because there are these differentiations and these different insects that are attacking it, I felt an obligation to to talk about it either in presentations or even on the the webinar that you just just mentioned right now. Okay, so we are talking about bricks and a lot of the listeners of the program today are gonna say how do I even know what the bricks is of my fruit tree?
Can I look at the tree? Can I see? This is a healthy tree. It's got green leaves. It looks good. It must be high bricks. Is there a way for home growers to be able to measure the bricks of their tree? Yeah, you can look at it if you're that good. It's difficult in order to differentiate between, let's just say for example, 10 bricks and 11 bricks.
Something like that is not easy for the eye to tell. But yes, you can clearly see the difference between an 11 bricks tree and a three bricks tree. That's about as clear as day. At least it's it is for me to to see. And many other consultants can also tell whether a tree is healthy or unhealthy based upon that.
But in order to tell we, we just prefer to test being, a scientist. It's always better to test rather than just to eyeball it and to get an idea. And so in order to do that, if we're gonna go after leaf bricks which generally we do we are going to take a leaf, if not several leaves, depending upon the size of the leaf, and we will crush the contents of that leaf.
And this can be done in a a lot of homeowners use a garlic press which is relatively small, doesn't hold a lot but if you've got leaves that are moist enough on the inside then usually you can get two or three drops, which is all that's necessary in order to to determine bricks.
But for someone like me, I prefer a a leaf a SAP press. And this enables me to do a hundred samples. In a couple hours if I'm out on an agricultural field working for a farmer who is looking to get an, I get an idea of how healthy his his crop is. So it's this, it's a matter of simply crushing the leaf and then taking the liquid content, not the solid content.
Taking the liquid content, which includes everything. It includes the flown tissue, the xam tissue liquid, and it includes the internal part of the epidermal cells, the internal part of the meso fill cells. It will include the aplastic region. All of the liquid is crushed out, and then that liquid, usually only two or three drops is necessary, is placed on a device called a refractometer.
We measure the bricks level on that refractometer. It usually can be done as little as two seconds. If you're looking through a viewfinder, it can take as much as five to 10 seconds, so that's a little bit slower. And that's how we do it. And then we just clean off our refractometer and we go at it again.
And usually I'm doing multiple readings at a time. The homeowner, probably would not be doing something that I'm doing and so our garlic press may be attractive if that works out for them. You can also do the same thing with fruit but the fruit bricks is a little bit different. That does not apply to the 12 bricks rule that I just mentioned.
That is a leaf bricks rule. Yes. So fruit and just to say that there are refracts that we can get as homeowners and Yeah. And small scale growers that are online that are, what, $35 or something? Sure. Maybe 50 bucks. Yeah. So this is something that we can have fun with too. Measuring the bricks of our trees and as it changes through the seasons.
Oh sure, absolutely. If you're doing this on a weekly basis, incredibly valuable information is to take a look at your crop on a week by week basis to see how the bricks changes. Many people over are interested in also doing the fruit as well which can easily be done with bricks. It's just it's on a different scale.
It's usually on a higher scale because there's a concentration of sugar, which is always placed in the fruit. This is why we eat the fruit is because it's sweeter tasting. So because of that, there are different scales for the various fruits that are out there. And it's al almost always gonna be higher than the leaf bricks.
But that is also a useful bit of information for the fruit grower to know, is that yes, you can measure the fruit. The problem is not very obvious and you're probably thinking this already, is that you don't have fruit on your tree 12 months out of the year. And so if you wanted to measure how healthier tree was, you are gonna have to rely upon leaf bricks in order to make that determination.
Okay. We've got a few emails. A whole bunch of emails have come in. We've got one from Gail, from San Diego, California. Hello, Susan. Thanks to your guest for explaining what that sticky poop is On my car under that tree. I was always wondering. You are welcome, Gail. Okay. Okay. Now we have an email from Carrie.
Carrie says, my name is Carrie. I'm from Bend, Oregon. I would like to be entered into the draw. Thank you for sharing you your and your guest knowledge through your radio program. Thank you so much, Carrie. I love the fact that you're able to share it with me because I have fun on this show interviewing fabulous people, and I love to share my passion with my listeners.
Okay, now we've got another question from Carrie. How do I see that chart you're talking about on my computer? So Carrie, I am going to have that chart. In the video version of this podcast and I will put it on the show notes for the podcast too, but I, that's a great question. So I'm going to ask you, Thomas, can you describe the chart and tell us what people see?
Okay. So if there's a replay of this and you have the chart in front of you, you'll be able to follow along. So right now, I'm just gonna have to get into your imagination. But the chart has four different categories listed from one bricks up to 20 bricks. The reason why I stop at 20 bricks is because it's virtually impossible in order to break 20 bricks on the leaf.
It is not impossible on the fruit. There are lots of fruits that can be in the in the 20 region. So that's not uncommon at all, but. For leaf bricks, it really doesn't go above 20, and so these four different categories are broken down so that people can understand how healthy a given plant is.
The first category that I have is between one to two bricks in the one to two bricks region. These are plants that are, of course, they're unhealthy. I think everyone knows that based upon what I've said thus far, but these plants would get picked off. In nature. These are plants that do not survive in nature.
They are unhealthy and they will get picked off by insects or disease or they just will not be able to grow effectively. And so because of that usually force feeding is necessary. You have to force feeded these plants. They need nutrition usually on a daily basis in order to survive. Otherwise they will die.
And so that's the first category that we have seen. The second category is between about three to seven. Three to seven is where I find most of the crops that are grown in this in this country found. And so they're not doing great. But these plants do have a fighting chance and a lot of these plants look.
Okay. They don't look that bad. So if you go out into a field, you'll see a lot of these three to seven bricks plants that are doing all right, but sometimes they're being attacked by disease and by insects. And they're gonna need some help. And so usually the farmers, for example, would be feeding them at probably at least once a week depending upon where they are in that region.
The next region is about from eight to 12. And in that region at that point health really starts to become evident. And the plant becomes so healthy that it actually develops a very. Good insect resistance, and a lot of insects will no longer be interested in a plant once it gets between about eight to 12.
And there are various insects that will literally fall off the plant or stop feeding when a plant is reaching 8, 9, 10, 11. And and 12 bricks. This is what I call a sword and a shield because the plant can defend itself very well against these pests if it is attacked. And sometimes it can be because it's not as high as it should be.
But they've usually got some defenses and they can probably handle themselves pretty well. And then finally, the last category is 12 and up. Where we what I say is that food is now produced. Food being a meaning food that you can consume that will lead to a long, healthy life. So I'm not talking about snack food.
That's food that fills the stomach. It's temporarily there, but. As far as good, healthy food, you're gonna want something which is gonna be 12 and above. I prefer to tell people is that you really should be shootings for 14 bricks because there are some fluctuations at either the time of the day or sometimes during the season where the bricks can change easily two bricks at a time.
And so if you're shooting for 14 bricks and you shoot down to 12, you're still gonna be in good shape. But there are issues like if you're st, if you're going into fruit production and your bricks levels are at nine, you're probably going to be in trouble because a lot of that. Even though that's a pretty good level, a lot of the sugar will be taken into the fruit and then not that much will be left and the tree will start to suffer unless it can pick up photosynthesis and do that.
So usually we're looking for a good healthy tree as it goes into the reproductive. Phase 14 is a good number to shoot for. Certainly it can get higher. There are lots of trees out there that are higher than 14 bricks, but if you're hitting 14, you're gonna be in good shape as you go through this.
So those are the four categories of the chart that I have. Gotcha. Okay, so a few quick emails here. We've got Kyle, who writes, Susan, does your guest have a website to recap all of this? And Kyle is from Toronto, Ontario, Toronto, Kyle. I've been there many times myself. I grew up in Rochester, New York.
That was only a three hour trip around Lake Ontario. Are you in ro? I have to interrupt. Are you in Rochester? No, not right now. I grew up in Rochester, so did I. No way. City. Yes. I grew up and was born in New York and then IIG Immigra, not immigrated, but I moved to Rochester and I ended up before I immigrated to Canada living in Webster, New York for many years.
Yeah, my brother still lives in Webster, New York. I grew up in Henrietta, New York, and familiar with all the suburbs around there. I didn't actually grow up in the city of Rochester. We were in the suburbs, mostly in Henrietta. But yes, that's where I grew up. That's where I spent, I guess you could say the first until I was 22 when I graduated from Cornell and then came down to Florida and have been in Florida ever since.
Oh, we'll have to talk. Thank you Susan for acting me now. Alright. That was Gary in the studio. So yeah. So a website or some resources for people who are interested in learning more about what we're talking about today. Yeah, the website is not going to be that descriptive. For many people. Many people are usually shocked when I mention this, but I have been an industrial entomologist my entire career.
All of the research that I do is proprietary. I don't publish, I don't have that information available. And so because of that becomes a little bit problematic. However I've just become affiliated with a e a advancing eco agriculture. They have been familiar with what I've been doing for a long time and they asked me if I would do some webinars.
So the webinars are. Are coming fast and furious right now. So already I've got I think we've got six webinars which are online right now. And I've also got a number of podcasts. And when I'm finished with this, I guess we'll have Susan Poizners podcasts too. So the information is getting out there and the things that I talk about are not proprietary.
These are things that I've just noticed over the past couple decades and that I felt was important enough in order to to speak about, in order to help people who are, looking for information rather than just being told, for example, that this is just what you need to do. Raise a plant, throw this pesticide on it, throw this fertilizer on, and everything is just fine.
And I have since have enough information to know that it's not that simple and that there are other ways in order to raise plant. And that there are lots of signs too. And these signs are partially what we're talking about right now with Susan, with the chart and things like that.
These tendencies that I have seen with the insects. I feel now that I'm getting the information out, which is fantastic. It's been 20, really 25 years since I graduated with the PhD. And now this has been a really big change in my career because once these webinars came out, they became popular and I realized that there was a need, a desire in order to find this information out.
And What can I say? I feel okay, if this is what people want to hear, then I'll go ahead and and talk about some of these details in order to help not only the Backyard fruit grower but also as many farmers as I can in this process. And that's been what I've been doing easily for the past year and a half.
Thank you so much, Kyle, for that excellent question. And that's how I found out about Thomas by finding one of those wonderful webinars. Very much worth looking for. So thank you Kyle. Let's take a moment to listen to some some sponsoring messages. And after the break, I'd like to dig in a little bit more.
To talk a little bit more about bricks, about how this all works and how we as homeowners or home growers or arborists or gardeners, how we can use this information to make our fruit trees healthier and more productive. So Thomas, are you okay waiting on the line for just a minute while we listen to some commercials?
Of course. I'll still be here, Susan. Okay, great. Thank you so much. All right you're listening to the Urban Forestry Radio Show and podcast brought to you by the Fruit Tree Care training website, orchard people.com. This is Reality Radio 1 0 1, and I'm Susan Poizner, author of the Fruit Tree Care Books, growing Urban Orchards and Grow Fruit Trees Fast and we'll be back right after the break.
If you are thinking of planting fruit trees and you're looking for a wide selection of cultivars, consider wiffle tree nursery. Our 62 page full color catalog includes over 300 varieties of fruit and nu trees, berries, grapes, and other edible perennial plants. Not only that, in our catalog, we help you through this election process with tips and advice about all aspects of growing fruit trees.
You can learn about adding nitrogen, fixing plants, root stock choices, and even about planting a wind break if you have a windy site. We are a one-stop shop as we sell fruit tree care books, pruning tools, organic sprays, and natural fertilizers. We're located in Allora, Ontario, but we can ship all over Canada.
Call us at (519) 669-1349 to order your catalog. That's (519) 669-1349 Wiffle Tree Nursery. Call us today.
Hi everyone, it's Susan from Orchard people.com. Do you have a question about growing fruit trees? Maybe your tree is struggling with pest and disease problems, or maybe it produces poor quality fruit. If you are looking for the answer to these problems, pick up a copy of my new book, grow Fruit Trees Fast.
In the book, I'll teach you what you need to do to keep your fruit trees healthy and productive, and as a bonus, the book takes just one hour to read.
Go to amazon.com or your local Amazon store and search for grow fruit trees Fast by Susan . I hope you love the book and that it helps you have healthy and productive fruit trees.
If you are listening to this show, you are passionate about fruit trees, but do you care how your trees are grown? Silver Creek Nursery is a family owned business and we grow our fruit trees sustainably using only organic inputs. We s stock a huge range of cultivars like Wolf River and apple tree that produces fruit so large.
You can make an entire pie with just one apple. We also carry red fleshed apples like pink pearl, as well as heirloom and disease-resistant varieties of apples, pears, apricots, cherries, and more. We ship our trees across Canada and we can also supply you with berry canes and edible companion plant to plant near your trees.
At Silver Creek Nursery we grow fruit trees for a sustainable food future. Learn more about us@silvercreeknursery.ca.
Welcome back to the Urban Forestry Radio Show with your host Susan , right here on Reality Radio 1 0 1. To get on board right now, send us an email. Our email address is in studio101@gmail.com.
And now right back to your host of the Urban Forestry Radio Show, Susan Boisner. You are listening to the Urban Forestry Radio Show in podcast, brought to you by the Fruit Tree care training website, orchard people.com. This is Reality Radio 1 0 1, and I'm your host Susan Poizner. In the show today, we've been talking about why pests attack fruit trees and how we can stop them in their tracks.
My guest on the show today is an entomologist and a regenerative agricultural consultant, and his name is Dr. Thomas Dykstra of Dykstra Labs in Gainesville, Florida. So Thomas says that fruit tree pests only attack unhealthy trees. And in the first part of the show he explained that it has to do partially with an insect pests digestive system, healthy fruit trees have a lot of sugars in tho in their biomass, and those sugars will be in the leaves as well.
And according to Thomas, Too much sugar in the leaves and in the tree can deter insect pests. So in just a minute, we'll talk about a little bit more about how to measure the amount of sugar circulating in your fruit tree. But first I do want to hear from you. Send us an email during the live show today and I will enter you into today's contest.
And it's a brand new book by Joe Lampel. The book is called The Vegetable Gardening Book. Essential guidance for growing vegetables like a pro, and the book is valued at 24 95. To enter the contest, all you have to do is send us an email right now to intu 1 0 1 gmail.com. Send in a question, a comment, or feel free to write us just to say hi.
So that's in studio one oh one.com at gmail.com. And remember to include your first name and where you're writing from. I look forward to hearing from you. So back to Thomas. Hi Thomas. We got Hello, Susan. Hello. I got, when I put this out on Facebook before, before the show, I got some interesting comments.
I'm gonna read one of them from, I've got a couple of them here. First one is from Michael. I don't know where Michael's from. Michael says, interesting. I have not tested the leaf bricks on my fruit trees, but I assumed the opposite. So the opposite that. Anyways, I'll read on, I noticed that Japanese beetles love to eat, leaves for trees that produce high bricks, apples, honey crisp is their favorite.
That's what Michael says. So how would you answer that question? Test. So if you have Japanese beetles attacking the apple tree, I would test the leaves especially the leaves. Maybe they haven't been attacked yet because they're pretty good at at taking a leaf down to nothing.
But there should be a few available leaves and you should be able to test them, and that will give you an idea and you will find that the bricks levels are gonna be well below 14. You'll not be dealing with a ha with a healthy apple tree at that time. So when you mention high bricks, it do need to differentiate because the apples will be higher.
The apples can be higher than 12. They're not attacking the apples. Mind you, they're attacking the leaves. So if you have a lower bricks fruit than usually other insects will come in and attack that. But we are talking about the Japanese beetle now. And so if you test, you will see that the bricks is going to be lower than you would like.
As I said, well below 14 for a Japanese beetle I'm thinking it's probably gonna be somewhere between seven and 10 bricks is going to be my guess on that particular insect. They could be attacking an 11, but they're not gonna last long and you're not gonna have large quantities of them.
The higher the quantity of Japanese beetle, the more indicative that this is a plant that they can digest easily and it usually means a slightly lower bricks. But as you get higher and higher, the Japanese beetle will be unable to to digest it, and they will move on to your neighbors.
Tree and start attacking that assuming you know that you're doing a better job than your neighbor. And I think that's a really interesting question because it really is about differentiating the bricks or the sugars in your tree versus the bricks in your leaves versus the bricks in the fruit.
You can have super sweet fruit and. An unhealthy tree, is that the case? It is possible. It's not usually possible to have, I'm not use the word. You used a super sweet in order to have a super sweet fruit you're gonna have relatively high bricks leaves. So down here, just to give someone an idea I would be looking for a minimum of difference of three bricks.
So if I'm gonna be dealing with 18 bricks, oranges down here, you're probably gonna need about a 15 bricks leaf in order to feed that orange. So I'm looking for at least three more is fine. It's not an issue. Certainly I've had many orange trees where you'll have a difference, four or five bricks levels, and that just means that the energy is being funneled into the fruit now with oranges.
The difference is not as severe, but plants can really s shunt a lot of their sugar into the fruiting structure, and it can be serious. With some of them I'm thinking of sweet corn where it can pretty much empty the leaves and everything goes into the corn and you can be getting 20, 20 bricks or more from the corn itself.
But the leaves are dying. But it's okay because the corn plant doesn't last. It's not a perennial. But on the other hand, you do have some plants like the grapes, which are problematic because they will s shunt a lot of. Sugar into the grape and usually the farmer's looking to get about 24 bricks.
24 bricks is what you're looking for when you're making wine. So most of the most of the wine growers will pick once they've reached 24 bricks, 25 bricks is nice, and they can get to 26 or 27, but if they've usually got a minimum of 24 bricks from the grapes itself, then they will start collecting it.
The problem is that if the tree is not healthy, it will not be able to sustain that sugar level, and the leaf bricks will go down to the point where it can actually kill the vine. And so there are cases where you can easily have a 20 bricks or higher, but a five bricks on the grape leaf, and that's usually a sign that the the grape.
Vine is in trouble when you have that kind of disparity between the two. So I'm guess I'm giving you a little bit, may, maybe more than you need to know, but I'm also trying to let you know that there is a difference between leaf bricks and and fruit bricks and that all of the sugar is made in the leaf, but eventually, It has to get to the fruit and it's that process.
If it's healthy the plant will do fine. It'll be able to shunt the the the sugar there and it'll still have enough to keep a healthy leaf, especially if it's gonna be back next season such as the grapes are. But every once in a while we do know that vines will die. And that's because they can be pushed too hard and in some cases they're not able to to sustain themselves when they do.
So most of the fruit trees are usually in pretty good shape. There are some cases, I think many of our listeners are aware where you will get a break. Sometimes a tree wants a break, and you will get an every other year. Harvest from your fruit. So these are the cases where the tree just needs a chance to breathe.
It may not be doing as healthy as you would like, and because of that, every once in a while, taking a break is a good thing for the tree so that it can come back and give you some nice, sweet fruit the next time. Other trees, they can do it every year and they're doing just fine. Many listeners, I'm sure are also known about thinning.
Thinning is sometimes important too. If there are too many on there, the tree thinks it can handle it, but if it's not handling it very well then if you start thinning the tree, then the sugar will start to be concentrated in the remaining fruit and that will usually increase the the sweetness of the fruit that is remaining.
Little tricks I think everyone is aware of, because obviously this show is all about fruit trees but I'm just trying to get everybody thinking and to thinking about their plant and how the tree is reacting when it's producing fruit and even when it's not producing fruit. Amazing. And so really it makes you think about I think even about pruning fruit trees as energy management, you are directing sort of the juices in the tree, the energy in the tree to fewer branches so that those branches have more energy and to think about thinning the fruit.
When you're removing baby fruit, you are, allowing the tree to send more of that energy into the remaining pieces of fruit. So it's super cool like that. Okay. We've got a couple more emails here here. This one is from Michael from Eagle River, river, Alaska. Hi, Susan and Thomas. Do these concepts apply to invertebrates such as slugs and snails?
Yeah, being the the entomologist I can tell you that my my background in the mollusks is not that good. So from what I have noticed I have not seen a lot of snails in my travels. But when I do see them they are also tacking unhealthy plants from what little I can see. They prefer mushy stuff, so the plant's gotta be pretty mushy in order for them to eat it.
I don't really see in my experience, a lot of the snails going after relatively crisp plants and leaves. It's usually some weakened spot and then they start going after that soft spot. And then obviously things can escalate from there. So does it apply to mollusk? I'm not an authority on them Even though I'm not an authority I can offer you my opinion only.
And so my answer is yes. I do not see snails attacking healthy trees, whether they be the citrus trees that we have down here or some of the other places. I have not seen it myself, but I don't have enough background in order to certainly give you a chart or anything like that. Explaining what is going on in the mind of a a snail in the little mind of a snail little mind.
You wonder what he, what that he or she is thinking about that snail. Anyways. Okay. And Michael writes us again with another good question. How I love this. How quickly can the bricks levels change from unhealthy to healthy or vice versa during the course of a season? During the course of a season?
That depends upon too many factors. And because it depends upon too many factors, there is no set amount. Let me tell you about a quick example and you, let me tell you about a slow example. A quick example is if you have a low bricks plant, let's just say it comes in imaginary number 4.6 bricks.
You're in trouble. You have an addendum that you wanna put on. I don't know what it is, make it up. It could be a mineral, maybe it's short cobalt, I don't know. So you put down some amendment onto the tree, go back and measure that tree after you put it down. So you measure it before, and then you measure it after and within you sometimes within a few hours.
But usually I tell within 24 hours test that tree to see whether or not it liked the amendment. It will tell you that fast. Within 24 hours, the tree will tell you. So if you're at 4.6 bricks and then you go back and measure it 24 hours later and it's at 5.9, that's a pretty big jump for 24 hours.
And that's just telling you that the tree liked what you put down. That's all that it's saying. Now, some of the listeners are saying 5.9 doesn't sound healthy. Yeah, I get that. But you're trying to go in that direction of getting up to ideally 14 bricks. And so you're doing that right now. You put an amendment down.
I have talked to some people who put an amendment down and they'll get a jump of two to three bricks, so it can go really high, really fast in a short period of time. If. The plant is the wording is, let's say it's starving to death. Let's say it's starving to death. So when I say starving to death, you're thinking, what do you mean?
The plant looks like it's healthy, it looks like it's good. But take a look at what was happening when the ships were coming across the Atlantic Ocean and to the United States. A lot of the sailors were dying from scurvy. Scurvy is an absence of vitamin C, and so it was killing them. And once they got vitamin C, fresh fruit, so appropriate for this show, once they got some fresh fruit and some vitamin C in their system, they had what looked like a miraculous recovery.
It wasn't a miracle. It wasn't, oh, if you take this fruit, you know you're gonna become superman or anything like that. All it's saying is that there was a deficiency. The deficiency was taken care of and that now the individual is healthy enough, let's say, to cross the ocean and make it to, to the new world.
So scurvy is not a problem anymore because we understand it to be but if you have a single deficiency, meibum, Cobalt, iron. If you've got a single deficiency and it is holding everything back your fruit tree, which you could determine through a little bit of testing, if you put down that nutrient, you can notice a very big jump.
Not only will you notice a change in health just by eyeballing it, but you can also measure the bricks and there will be a difference and it'll easily jump up one bricks or more. It can't do less than what that just means that it's not as useful. But that's the type of thing that could be done on the short end of it.
Now, to answer it on the long end of it, yes sometimes it can take a season or more based upon what you're starting with. So if you have started with unhealthy soil, you just went out and you bought some new land and it was massive amounts of pesticide, androgynous fertilizers are being thrown on it for three decades from the pursuit that had it before, and you buy it and you want to go out and you wanna start planting whatever it is you wanna plant.
You're gonna have issues because the soil is not healthy to begin with, and so you're not gonna be able, you should not. If I was your consultant, I would tell you don't be looking for 14 bricks on the first season. It's just not gonna happen. There are a lot of things that need to be cleaned out of the soil, and so there are limitations as to how quickly you can go.
There was a situation we had down here where we were looking at some citrus trees that were in bad shape, and they were two bricks when we started. We got through the season. And by the entire, the, when the season was over, we were at nine bricks. Now it's a huge jump of seven bricks, but all of us were disappointed because I thought, why are we only at nine?
And then we found out that the farmer was spraying pesticides without our knowledge and therefore compromising the very system as we were trying to put various nutrients down in order to help these young citrus trees. They were probably only about two feet high, so they weren't producing fruit right now.
But we, once we found this out, we dropped the farmer immediately because we no longer had trust going on between us, cuz we asked them, not to be doing stuff like this. But that, that took an entire season just to give you an idea. So from two to nine, whether you consider that good or bad, and it's both.
It's both good and bad because we're only at nine. That's that, that took an entire season in order to do that's the short answer and the long answer to your question. So it can go in either direction, and it really depends upon factors. So we have a few more. Time is running out. I can't believe how quickly this show has gone.
But let's go through a few more quick questions. We've got lots of interest today. This email is from Esther. Esther says a great show. As always, please include me in today's contest. Thanks Esther. And what else do we have here? We've got a message from Scott. Scott says, hi all. I planted a couple of apple trees this spring, honey crisp and northern spy.
They were both terribly attacked by cedar, apple, rust, almost to the point that I had to ude the entire trees. All the leaves were affected. The trees leafed out again by the end of summer. Do you have any advice to control the cedar apple, rust next year? That's from Scott. Owen Sound, Ontario. The the rust is gonna be a problem.
It's a fungus infection and taking care of it. Obviously the common way to take care of it is through a fungicide. Copper fungicides are pretty common to be used among apples, and this is probably what most apple growers are using in order to do that. For those of you who are purely organic and are, they're not gonna be using, let's say, a copper fungicide.
There are other ways to do it. You can certainly introduce copper in a chelated form if you needed to introduce it, assuming that there may be a shortage of it in the in the leaves or in the actual apple tree itself. So there are these various factors, but I would test to find out what it is deficient in and then it would have to be satisfied.
Apple trees, for example suffer horribly when they have a cobalt deficiency. This is not the answer you were expecting, but when there is a cobalt deficiency, when deficiency, I'm talking zero. They cannot produce nitrogen at that point that everything just stops and very serious problems will result.
And some of these fungal infections will happen in part because of a cobalt deficiency, not necessarily a copper deficiency. Th these are just two examples that I give you possibilities to take care of. I wouldn't wanna suggest something, even though I am suggesting some things right now because I wanna help.
But I also understand that without testing we, I may be able to give you, I may be giving you the wrong advice, but I do wanna give you a couple ideas as to how apple trees work and that sometimes they're gonna need a little bit of help. And then once they get that little bit of help, they can start fighting off some of the disease themselves.
So I hope that was helpful. I tried to get specific without getting too specific. I think that's great. Yeah. Okay. Couple more quick questions. Hi, Susan and Thomas. This is from La Bloomington, Indiana. Hi. Hello, Susan and Thomas. If your tree has hybrids and deemed healthy, will your tree also be able to protect its fruit from insect invaders?
Generally yes. If you are looking at a 14 plus bricks tree and it is now sending, and the fruits start coming out and the sugar is being sent into the apples little by little in order to make a full, fully ripe apple no, you're not gonna have trouble with the fruit. If you do have trouble with the fruit, there are other things going on, and I'm not even sure if I can, do this justice in the minutes that we have remaining.
But if nutrients are not moving around the tree properly, then there are going to be issues. Let me just use one example, boron. So if you've got good health, if you've got 14 bricks leaves, for some reason they're not making it into the apples, I don't know what's going on. There could be a boron deficiency because boron is like the elevator in the plant.
It transports sugar up and down the plant and allows sugar to move freely within the plant. If you have a boron deficiency, the sugar's not moving within the plant, which means the apples are not gonna be getting not only the sugar that they need, but the other nutrients, the minerals that they need in order to make a nice crisp.
Apple, which is how apples are supposed to taste. If they're mushy. They don't have the mineralization that they need. If they're crisp, they have the mineralization and insects are not going to be attacking an apple that is coming in at 16 to 19 bricks. So last question for today. We'll wrap up with this and thank you Aldo, for sending in this question.
Aldo's in Toronto. And lovely wrap up question. So Aldo says, do you have any solutions to help the leaves that are problematic? I e increase the sugar range. So I have some suggestions as well that I would love to put forward. But what would you say in. 30 seconds, how would you summarize in just a few words how to care for your tree so that it does have hybrids?
There is no short answer to this. So if the shortest thing I can think of right now is throwing as much nutrition at your tree at once. If you're not sure and you don't have time to test or even maybe the money to test or you don't want to test, just throw as much nutrition at the tree as you can and just, I understand you're maybe putting a lot of unnecessary things down, but that's the shortest way to get where you need to go.
Put down the necessary amounts of good nutrients, not the, don't use the pesticides. I would not use a lot of the nitrogenous fertilizers, high salt fertilizers. I would definitely be leaning towards the me, the hundreds of nutritional supplements that are out there and available for many of the plants.
Most of them will do you good. Most of them will do you good. So I wanna refine that just a little bit. So what you're saying please. Yeah. So what you're saying is give the tree some loving, it needs loving, right? Yeah. But the problem is that if it's a home grower that doesn't really know and goes to the garden center and just grabs a whole bo bottles of this and bottles of that, you can actually really damage your soil like permanently.
So I have some gentle. And I have some gentle suggestions that you can throw nutrition at the tree. I would say to listeners, go back to episode 69 of the Urban Forestry Radio Show, and guess who my guest was? John Kemp, who you know very well. So John Kemp in that show talks about fruit tree foliar sprays a great way to throw nutrition at your tree in a way that it can boost photosynthesis and create its own nutrition to support it.
So that is a beautiful way to boost nutrition for the tree. And actually what people do with these holistic foliar sprays is exactly what Thomas said. You do the bricks before the spray when it looks a little sad. You spray and you come back the next day and you check again. I haven't done that yet with the bris, with the refractometer, but I can see the following day that the leaves of the trees get greener and the tree looks so much happier.
I also wanna suggest to people go to orchard people.com/sign-up, signup. So orchard people.com/sign-up. And I have, if you sign up for my mailing list, a free ebook that you'll get, which give you some great ways to fulfill your tree's needs in many ways, including nutritionally. So whether it's giving it compost and at what time of year to do that.
So grab that book. I think that will help too. And of course, I've had so many awesome experts on my show, like Thomas, who have talked about mulches and all sorts of fertility management. So check out those shows too, Thomas. You are amazing. It is so fun to talk to you, and it's so exciting to have this different look at fruit trees and plants and how we can protect them from pests without, spraying them with really toxic sprays.
Is that something that you have strong feelings about how, people rely on these sprays by killing the pests? I have strong feelings about it because I know that if you test the bricks and then you spray it with a pesticide and then you retest again, the bricks goes down. So yes, I have strong feelings about that.
Oh, we have, we, we can document it. We know that the pesticides are not helping the tree when we spray them and we test it with bricks. So I didn't mention that, but. But absolutely you can go in the other direction too. If you give the tree something that it doesn't like. It will also respond.
And some of the things that it will respond unfavorably to our many of the pesticides that are out there. And the other thing that I want to just say is I love your idea of us taking a more hands-on approach to actually monitoring our trees. I love that idea. I hope some of the listeners will try and keep us posted, testing the bricks, do a little graph, see how things go, and write us@infoorchardpeople.com.
I'd love to know and I'd love some follow up on how people do with it. Thank you so much. Our time is pretty much up Thomas, but I hope you will come back again. We have, I don't mean to interrupt you, but we have a book to give away. We have a contest. Oh my gosh. And Gary is allowing us to stay on the line for a couple more minutes.
Gary. Yes, Chris, the winner. Okay, so here's what we're gonna do Dr. Dykstra. What we're gonna do is I'm gonna, I put all the names in a bucket and I'm gonna shake that bucket. You'll be able to hear it. Tell me when to stop and then I'll pull out a piece of paper. Okay. Are we ready? I'm ready. Here we go.
And stop. All right, let's see what we have here. If it's my name, this is gonna look really bad. Gary, it looks like Stephanie d from Kansas City, Missouri. Congratulations, Stephanie. Congratulations, Stephanie, sorry about the ringing phone in the background. That is wonderful. Stephanie, we are going to write you and we will get you your copy of the Vegetable Gardening book by Joe Lampel, who everybody is really excited about this book.
This is a wonderful new book. So congratulations. I also wanna flag, I love it when people write me in between shows. So I also wanna say thank you because I got a lovely email this month from Carl, from Milwaukee, Wisconsin, and he wrote, he said hello to Susan. Enjoy this coming long weekend holiday.
Get out there and plant. Prune or eat some fruit. Isn't that good advice for anybody? You wanna have a good day, do one of those things. So thank you so much, Carl for writing. Thanks everybody who participated in the show today. Thank you, Gary, for giving us an extra few minutes. You're welcome.
And thank you so much, Thomas, for being on the show and I hope you will coming back again. I'll be happy to do Susan. Thank you. Okay. Take care. So that's it for today's show. Wow. Thank you for tuning in. If you want to go back and listen to this show again, and you may well want to do it because it's been so packed with information, all you have to do is go to orchard people.com/podcasts.
And if you wanna see a video of this podcast, hang in there a couple of days and go to the Orchard People YouTube channel. I'm going to take some information, some images, and those graphs that we have from Thomas. I'm gonna put them in a video and so it'll help us visualize what we've talked about today.
So that's on Orchard People's YouTube page. Finally, if you really want to learn how to grow fruit trees and you don't have a lot of time, grab a copy of my new book Grow Fruit Trees Fast. You can read it in just under an hour. So to purchase your copy, visit orchard people.com/growf Fruit. Or search grow fruit trees fast in your local Amazon show store.
So that's all for today, everybody. Thanks so much for joining me. I hope you will come back again next month. We've got another great topic and another great guest. Take care, and I'll see you next time. Bye for now.
You've been listening to the Urban Forestry Radio Show on Reality Radio 1 0 1. To learn more about the show and to download the podcast where I cover lots more great topics, you can visit orchard people.com/.