Orchard People

[00:00:00] New Year's Resolutions for Fruit Tree Growers
It's December 31st and the dawn of a new year and a new decade. What's your New Year's resolution? Some people decide they're going to go to the gym every day. Others say they want to read more books and expand their minds. And fruit tree growers like us, for many of us, our goal in 2020 is going to be to learn how to care for our fruit trees more effectively.
And Lord knows, fruit trees can be a handful. You plant them with lots of love and hope, and then they go and catch every fruit tree disease that's going around. Or they get hit by a swarm of this year's newest and scariest fruit tree pest, which makes a mess of the tree and destroys a good part of your harvest to boot.
And people think children are high maintenance.
[00:00:51] Introduction to Organic Fruit Tree Sprays
in this episode of the Urban Forestry Radio Show, we're going to talk about one piece of the fruit tree care puzzle, and that's the use of organic fruit tree sprays. Now, I know folks who would just go to the garden center and find a spray that says, fruit tree spray, and they might just use it whenever, whether it's appropriate or not.
Even if it's organic, misuse of that spray may actually damage your tree, your health, and the environment too. But in this show, we're going to get into a little bit more detail. most sprays are only effective and safe when you use them in the right conditions and at certain times in the growing season.
So we're going to talk about that today with orchard consultant, Mike Biltonen. Mike has horticulture degrees from Virginia Tech and Cornell, as well as over 35 years of practical farming experience. His focus is on working with orchardists who want to grow their crops more holistically. Mike lives in the Finger Lakes region of New York.
Now fruit tree sprays are just one tool in your toolbox when it comes to protecting your trees. You can learn about lots of other tools in my award winning fruit tree care book, Growing Urban Orchards.
So now let's dig into today's topic with Mike Biltonen, who is on the line right now.
Mike, welcome to the show today. Thank you.
[00:02:24] The Importance of Timely Spraying
Mike, when you are working, you're an orchard consultant, and when you are working with your clients, what role do sprays play in terms of protecting fruit trees from pests and disease? they play a very important role. There's a, quite a few insect and disease pests, that vary throughout the growing season, which, depending on what part of the continent or world that you're in, can begin.
in, late March to early April, say, in the, Great Lakes region, and last until October and even into November, in some cases. And so being able to understand what these insects and diseases are, and how to help your trees withstand the onslaught that can occur from time to time, year to year.
It's really important. And so doing nothing is not really an option in our climate today. But by the same token, it doesn't have to be super intensive. As long as we're choosing the right sprays for the right time of year, for the right insect and diseases, it really can help grow a healthy tree and healthy fruit.
So you say doing nothing is not an option and so describe to me what can happen if we just leave our trees and just don't use any sprays at all. probably the biggest thing that can happen, from a disease standpoint is the trees can get a number of diseases. Apple scab, cedar apple rust, there's a new one that we're dealing with called Marssonina leaf blotch, which if they get, Severe can actually defoliate the tree.
And if the tree defoliates, and this usually has, started to happen in late July and through August, probably two or three months before the tree would naturally drop its leaves, if the tree defoliates, then it can't photosynthesize. And if it can't photosynthesize, then it can't create the sugars and the nutrients and the compounds that it needs to stay healthy as a tree or to grow good fruit.
And by the same token, on the insect side, there are insects that, can not just, yes, damage the tree, but could, can actually kill it. there's bores of different types that will bore into the trunks or the twigs of the tree, that, if severe enough, can girdle it and eventually just cause the tree to decline.
So if we don't do anything, chances are that something will happen. and it can happen quickly, but usually it happens over the course of a few years to where the trees can just decline and die. And also if you are growing your trees in an urban environment or where they're more, they're closer together to other trees, these problems spread really quickly from tree to tree.
So if one neighbor in a neighborhood is growing a fruit tree and they let it go, All the other trees in the neighborhood will come down with the same problem. Is that true? they can, yeah. It can spread fairly quickly and that's particularly true in the case of bacterial diseases and some insects that multiply quickly.
and can move fairly quickly in either the wind or the rain or just fly from tree to tree. yes, proximity is very important. Now, why is it important to do your research before you even go out and buy the sprays? like, why do you need to know what's going on with your tree? because one, is that not every region, it doesn't have to be a large geographic region.
It could be from, In New York, for example, the issues that we have in the primary fruit growing region along Lake Ontario are different from what they would have, say, on the Ontario Peninsula versus the Hudson Valley versus the mid Atlantic region of the U. S. we don't all have the same, And so understanding what your pressures are from, the insect and diseases, is very important.
But the other thing is that once you've got a handle on those basics, understanding the ebb and flow through the growing season of when certain diseases are problematic and when they're not, when certain insects are problematic and when they're not, is important, because that's going to help guide you to understand You know, one, if you need to spray anything, and then two, how to choose the most appropriate spray.
And that can change dramatically throughout the growing season from times when very little intervention is needed to other times where it can be fairly intensive. That makes sense. We have an email from Walter. Walter says, Hello, Susan. Happy New Year to you and your staff. A very nice topic today.
I can't wait until apple season again. No questions. Just wishing all of you a very happy new year. P. S. Listening from Calgary, Alberta. Thank you, Walter. That's nice to hear from you.
[00:07:38] Understanding the Dormant Season
So Happy Let's dive in to, we're going to do this season by season, and for this first chunk of the show, let's talk about the dormant season.
Mike, what does that mean? When does the dormant season begin for fruit trees, and when does that end? the dormant season technically begins at the end of a current growing season. as soon as a tree, the fruit's been harvested and the leaves are fully defoliated, And all of those carbohydrate reserves have gone into the roots and the trunk and the branches of that tree.
that tree is essentially dormant at that point. it needs to achieve a certain amount of chilling units or cold days before it could possibly start to grow again. Now, the dormant season will extend from We'll just pick a random time, say the middle of November, all the way up until the middle of March.
and then, in the middle of March, it starts to accumulate growing degree days, warm, during, warm days. And even though we won't see the tree start to grow, and it'll still look very dormant and asleep, and for all intents and purposes it is, slowly starting to wake up in the same way that with maple trees, the sap starts to rise before the leaves come out.
That sap, those carbohydrates are starting to rise again. But we see the real end to the dormant season when the bud scales on the overwintering fruit buds start to expand slightly. And we can see a change in color in the bark and in the buds. And that, even though there's not a defined period per se of when the dormant season ends, that's really when we can say, okay, It's game on that the growing season has started.
Okay, so you said there's not really one exact time. So it's not when the buds start to swell or as soon as the buds are open, dormant season is over. There's nothing that specific if we're analyzing our tree rather than looking at our calendar. Yeah, there's certainly not a calendar date, but yeah, once the, actually when the buds do start to swell, when you see that change in the color, you can say that dormant season is over and we've started that growing season.
Gotcha. But that could vary from year to year. I've seen it, in New York where, we've had The dormant season end in, or appear to end in early March. only to have more winter set in and in other years where it stays relatively cool or cold through March. and the trees may not look like they're waking up until, early to the middle of April even.
Wow, big difference. We've got a couple of emails here. One's from Aldo. Just listening for the first time. Aldo says, I often spray fruit trees with a combination of sulfur lime and copper mixtures, but don't have much success. We are going to talk about those things in just a moment.
And Eamon says, Hello, are there any natural pesticides for apple trees? Thanks. Happy New Year from El Paso, Texas. Thank you, Eamon. So we will also talk about natural pesticides. But now we, so we're talking about the dormant season and we have our questions here.
How are we going to protect our trees in the dormant season and why is this a good time to protect? The trees. So what would you say about that, Mike? just like the trees are sleeping and recovering during the winter. So are a lot of insects and diseases in their own way. they're going through a dormant period of their own.
And many of these insects and diseases will do their winter rest, on the tree itself. And some examples of those might be some mites or scales, woolly apple aphids, some diseases, particularly bacterial diseases like fire blight. They will be residing on the tree itself.
And so we want to be aware of that. And in order to reduce the pest pressure or the disease inoculum when the season starts, there are some treatments that we can apply that we need to think about, that will help to reduce the population, say, of overwintering mite eggs. And by getting a jump on the season, it reduces the potential for those pests and diseases to be bigger problems in season than they would be if we didn't do anything. So let's go through a list. In the dormant season, what are our options? And we had one person write in who mentioned copper and lime sulfur. And Eamon writes in about natural pesticides. Give us a list of what are our options in the dormant season and when would we opt for those different choices?
[00:12:36] Effective Dormant Season Sprays
one of the most classic options is just a horticultural oil, and the horticultural oil would be applied, in a dilute spray, and by dilute maybe 1 to 2 percent oil in water, and that would be applied to the entire surface of the tree, and what the oil does is it essentially smothers the mite eggs, or the scale, or the woolly apple aphids.
and that's one of the more classical, options that's available, quite easily to anybody. you can also add in, or include some other sprays, copper being one of them, lime sulfur would be another, and also neem oil and karanja oil. Which are seed oils from trees in India have also become very popular.
They act differently than horticultural petroleum oils. and they actually have some added benefits for the health of the tree. those are the, in the dormant season, those are the basic options that we're dealing with to help with these overwintering insect and disease pressures. And so if you are, like, how would you know when to use copper versus when to use lime sulfur?
how, do you make these decisions when you're working with orchards? so copper is very, very good against bacterial diseases like fire blight, or bacterial canker. There's other types of fungal cankers that are out there. it's also a good fungal protector, but It's much better as a bacterial treatment.
Lime sulfur is much better as a fungal treatment. the sulfur being, one of the primary components in that, obviously. and not so good against bacterial. understanding, if you've had, if you have a history of fire blight in your orchard, or if you've had a history of fungal infections in your orchard, you may opt for one or the other.
as a prophylactic, you certainly could apply both, and at the appropriate rate. you could cover all bases, and if you didn't know what your problems were, that might be the most appropriate approach, but again, knowing what your problems are from year to year, maybe one year you're applying copper, and the next year you're applying lime sulfur to, just depending on what your issues are.
And the other thing is that lime sulfur is also very good at controlling overwintering mite eggs. So it has a strong impact, as a dormant season miticide as well. Interesting.
[00:15:26] Fire Blight: Identification and Management
So actually Bryce writes us and his timing is perfect. Bryce says Hi. We always hear about fire blight. What is that exactly?
And Bryce is from Maysville, Georgia. So Fire blight is a, it's a bacterial disease. it's of worldwide significance in pome fruit, which is primarily apples and pears, but it also can infect hawthorn and raspberries and other plants in the Rosaceae family. the scientific term is Erwinia amylovora.
it was originally identified first and we think that it actually started in the Hudson Valley of New York. So that's our little gift to the planet. Fire blight is a bacterial plant disease that actually moves systemically or in the vascular system of the plant. The most important point of entry is through the blossoms in the spring, but you can also get infections through leaves, or branches, say, after a hailstorm or a heavy windstorm.
So it can enter through any type of opening, in the tree itself. But again, the most important entry point is in the springtime during bloom when it can enter through the flowers. and then once it starts to spread systemically, it not only will kill the, could kill the flower, but it can kill the spur, which is what the fruit bud is born on.
it can infect the branch, and in very severe cases, it can actually kill the tree. And there's some varieties which are much more susceptible to fire blights. And there are some roots, apple rootstocks, which are much more susceptible to fire blight than others. Yeah, it's interesting, and that's a great question from Bryce, and, what you would see, and sadly we've had it here in Toronto, and it's spread, there's some years that are worse than others, The branches look burnt out and they curve like a hook.
Sometimes people look at the tree and they think, Oh, this tree is okay. It just needs more water. No, it's got fire blight. So it's an awesome thing. If you've got fruit trees, in particular apple and pear trees, Google some pictures of what a fire blight affected tree would look like, so that, if and when it happens, you can recognize it.
Yeah, that's a good point, because symptomatically, Fire blight is exactly what you described, and It looks like the tree has been scorched or there was a fire. But the other thing to realize is that you can have infected tissue on the tree that is not symptomatic with the infection. And so one of the cultural techniques for controlling fire blight is actually to cut out the infected branches.
But when you do that, you need to cut beyond what you actually see by maybe about 16 inches. So if you have a, chute or a branch that's say, 36 inches long, the. You want to cut 16 inches below the last visible symptom of that to make sure that you remove all of the infected material because if you're just cutting through non symptomatic infected tissue, it's going to continue to spread in that tree.
Absolutely. By the way, there's a little clicking on the line, I'm not exactly sure where that's coming from. But sorry about that, guys. okay, so we've got an email here from Norm in Toronto. What are the benefits of neem oil? And also, can I just buy it from my local Indian grocery? As opposed to from the garden center as I heard it is cheaper. Would it be the same stuff? So that's from Norm about neem oil.
[00:19:08] Neem Oil: Benefits and Usage
Yeah, so neem is a very interesting material to use. pure neem oil originates from the neem tree in India. And in its sort of unadulterated shape, it has a consistency of peanut butter, and it doesn't begin to liquefy until it gets up above 60 degrees or so. And so what's happened is that manufacturers of horticultural products have started to strip out some of the constituents that create this very viscous texture at low temperatures. And what's left are products that are not referred to as neem strictly, but as like azadirachtins.
And there's a number of different azadirachtin products that are out on the market. Some are consumer, some are more commercial products. You still get a lot of the benefit, that you would get from using pure neem oil and you get a real advantage given that it's much easier to use, it mixes with water much easier.
whereas neem oil, there's a whole process that you have to go through to make sure that it's emulsified into the spray water quite well. So that's the long answer. The short answer is that it's going to be cheaper. It's not going to have everything that pure neem oil gets with it. but it's going to be a lot easier to use and yes, you will get benefit from it. So what are the benefits of neem oil? So we talked about how copper helps with bacterial diseases. Lime sulfur helps with fungal. We talked about dormant oil is great for smothering insects. Where does neem oil fit in here in our dormant season spraying? neem oil brings a number of properties with it, of course, you get the oil, so like a horticultural petroleum oil, you're going to get the smothering effect on mite eggs and scale and the like.
but you also get a number of constituents, fatty acids being one of them that are really important for feeding the microbiome that's on the surface of that tree. And that's a good way to help build the biological robustness of the orchard that provides additional protective benefits against diseases and insect invasions as well, but you also have this very interesting insect growth regulator characteristic from neem that helps to debilitate, reduce the development of other overwintering insects that are on the tree. And like with moths and butterflies, they go from an egg to a larvae, to a pupa, to an adult. So they have to go through these different life stages and the insect growth regulating properties of neem oil help to reduce the success rate of those types of overwintering insects. other insects such as, aphids and leaf hoppers, they go through different instars, which are just larger versions of the previous version.
Basically, the baby aphids look about the same as the adult aphids, except they just get bigger. They as well can help to reduce the development of those different instar stages. So you get three primary benefits. You get the oil, which is, an insecticidal. you get the fatty acids, which feed the microbiome on the tree.
You get the insect growth regulating properties that help to reduce the success rate of Certain insect species that might be overwintering on the tree. So does timing matter? You've given us a selection of a bunch of different options. Does timing matter? Should it be early in the dormant season?
Should it be late? Should we do one spray on a Monday, the next spray on a Tuesday, and the next on the Wednesday?
[00:23:18] Mixing Sprays: Best Practices
How do you consider, when to time your spraying in the dormant season? basically, especially when it comes to oils, or copper or lime or sulfur, each of those products, individually, but also together, if they're applied when there's foliage on the tree, you can get what's called phytotoxicity.
So you can get damage or burning of the leaves. And if it's even later than that, you could potentially get, burning of flowers or rusting of the fruit. And if you know that you have a mite problem or a scale problem, applying those materials, earlier in the dormant season, and so we'll say mid March, mid to late March or so, you can apply them at a higher rate and have a greater impact on those pest species populations.
The, sooner we get to that bud swell, bud break, and what we call green tip, which is when you start to see the very, first hints of green tissue emerge, we need to reduce the rates so that we don't cause any phytotoxicity problems in the tree itself. And so by reducing the rates, we're obviously going to have less efficacy against some of those insect and disease pests, but as well, those pests are starting to wake up and they become more susceptible.
So there's a little bit of a sweet spot and, I don't like to recommend applying anything too early in the dormant season. I also don't want to apply it too late because then, we have to reduce the rates too much. So somewhere right around what we call delayed dormant, so just as the buds start to swell but before there's that green tissue, that's really the sweet spot of, when you want to apply these for the most efficacy.
Now you can, what we call tank mix, you can put, each of these materials in a tank together, but you don't want to put them all in the tank together. So you could apply copper and oil, or you could apply, copper and lime sulfur together. and I would, when we're using materials like that, I usually recommend waiting, about a week in between each one.
Oil can increase the potential for phytotoxicity. it can also increase the efficacy of each of those materials. And so if you're tank mixing, or mixing any of those together, you want to be aware that giving them time to dissipate on the surface of the tree is important before coming back and applying another.
I just want to confirm here, so you said you can mix some of the things together, so you can mix horticultural oil with copper. Then you said you could mix copper with lime sulfur. Did you mean you could mix lime sulfur with horticultural oil? Or can you actually put lime sulfur? With copper because I thought I understood that those two don't get along copper and lime sulfur.
No, you can and I've applied them together, you know before. We do it in blueberries quite a bit Okay. Okay, great. basically, for those of you, and we're just going to go on to our next season in a minute, but for those people who are a little queasy about mixing their chemicals, you just don't know what's going to happen.
why should they be careful? what is it? Why should you do your research first before you just randomly mix your, different ingredients together in your sprayer? particularly when, oils or other caustic materials like lime, sulfur, or, even copper are involved, you want to make sure that you avoid any issues where you're actually damaging the plant.
We're applying these, and when used properly, they can provide a lot of benefit, both from a nutritional standpoint, but also, mostly from an insect and disease standpoint. we just want to be aware of what the interactions are between each of these materials. There's not always a need to have to mix different materials.
You can certainly separate them out, but you want to be aware that there can be these synergistic, negative synergistic, impacts by mixing different materials together. And then the other reason is that there's lots of different formulations that are out there. there are a lot of commercial products, formulations that are out there, and there's a lot of consumer over the counter formulations that are out there, and they're not all the same. Now, the consumer ones are generally formulated so that they're safe and easy to use, and there's, a low risk with using that. But still, if they're mixed inappropriately, you can get precipitates, you can get these negative reactions like mixing oil with copper and applying it at the wrong time of the year.
So understanding what your problems are, what you really need to treat, and what the interactions are between each of these materials is really critical. That's awesome.
[00:28:34] Preparing for Blossom Time
In the first part of the show, we talked a bit about the options for sprays that you can use on fruit trees during the winter dormant season, when our trees are bare, with no leaves, blossoms, or fruit. But when the weather starts to warm up and the trees get ready to blossom, what sprays can or should we use?
That's what we're going to talk about in this part of the show. Now, just to remind you, organic sprays are just one of many different ways that you can protect your trees from pests and diseases. And you can learn lots of other ways in my fruit tree care book, Growing Urban Orchards.
Mike, I just got an interesting email here from Tara.
Tara says, she titles it, Can you elaborate, if possible, apricot tree spray schedule? she says, Hi all, appreciate your response. Blessings for 2020, from Tara. in terms of the sprays that we talked about for our dormant sprays, are any or all of them appropriate for apricot trees as well?
Yes, and particularly in the case of stone fruit, of which apricots are a member, they can get bacterial and fungal diseases that apples don't get. And so the use of copper and lime sulfur in the dormant season can be particularly important to maintaining the long healthy life for apricots.
So that's good. And always, by the way, Tara, always read the packaging. Some packages, we've got a lime sulfur here, package mix here in Canada that says specifically do not apply to apricot trees. And maybe other trees are okay. So whichever choice you guys make in terms of what we're teaching you guys today, always read the packaging.
Okay, so now let's talk about blossom time. Mike, how do we define what blossom time is, when it starts, when it ends, and what should we be spraying during blossom time? blossom time, the flower itself is developed in the previous season. So the flowers that we're going to see in a few months were actually, and we're speaking about apples, Those flowers were developed last June and July, so they've been sitting in the tree.
benefiting from the growth. They're going through their dormant season right now. And when the tree starts to grow, that tissue will begin to differentiate, into the various flower parts. Now, if you have a compound microscope, you can see this at the various stages. But for your average, backyard gardener or orchardist, you're really not going to start to see, the beginnings of the flower until what we call, half inch green, which is a, it's a phenological stage.
[00:31:29] Flower Development Stages
And at that stage you can start to see the flower really begin to, swell up. And it looks different from vegetative buds, which don't have any flowers attached to them, simply because it's just bigger and plumper. And the next stage after that is going to be a stage that we call tight cluster.
And at that point, the leaves have started to unfold and the flower parts have pushed open. Now, it's still not a viable flower, it can't be pollinated, it can't begin to develop fruit because it's not fully differentiated, but depending on the weather, that could be anywhere from a week to two weeks, when we start to get the first, what we call open blossoms.
And that's when the petals and the sepals of the flower start to open up and you can see the pistil and the anthers, which are the, fruit bearing and the pollen parts of the flower that are inside of it.
[00:32:27] Bloom Time and Pollination
And at that point when you start to see the flowers really open, that's what we can call bloom time, the beginning of bloom time.
Now, not all flowers will open at the same time, so the first flowers may precede full bloom by a full week. but typically, in early to mid May, depending on where you're located again, you can see these first blossoms start to open. And then in central New York here, by the middle of the third week of May, we're definitely in full bloom.
Further downstate in the Hudson Valley. It could be earlier in May to the second week in May, so they could precede us by maybe ten days to two weeks even. But bloom time is when those first blossoms start to open, the petals are open, the flower can be pollinated, fertilization can take place, fruit development can begin, and then full bloom is when 90 percent of the flowers are open.
And then bloom time ends. will depend on the weather. So it's really hot and dry and windy. It could be done in a matter of days or if it's, relatively cool. and the weather is very nice. that bloom period can last anywhere from two and even up to three weeks long. But once it's over, then the flower will shed those petals and that period at that phenological stage is what we call petal fall.
And at that point, we can really start to see the receptacle. The flowers begin to expand and we can see the very first beginnings of fruit development. That's fantastic. It's a perfect explanation to help us understand that we're looking at the changes in the tree to decide what to spray and when to spray.
[00:34:14] Spraying During Bloom Period
So when those blossoms are open, do we spray anything or are they just too delicate that we should just leave them alone and say this is a no spray zone? Of course with climate change there's nothing normal about any year from year to year. But, in a more normal year where we don't have excessive heat or a lot of rain or that kind of stuff, typically I like to say that, it's best if you can avoid spraying anything.
Because the flowers are delicate. and if you spray the wrong thing or spray the right thing at the wrong time, you can damage those flowers and really have a serious impact on your ability to grow a crop of apples. Now that said, there are a number of insects and diseases that need to be considered and that growers need to be aware of because they can be particularly nasty during the bloom period.
[00:35:08] Fire Blight and Pest Management
Fire blight being one of them. As we mentioned earlier, that's when the tree is at its peak susceptibility for fire blight. Now there are conditions that need to occur in order for the tree to be susceptible to fire blight. But nonetheless, it's one that we need to be aware of. And insect pests, probably the most nefarious, is The European apple sawfly, which can infest the flower, the female lays the egg at the base of the flower right below the petals.
and then you get this larval development which kills it. And then oriental fruit moth can be another one, though it's not. necessarily as serious as, European apple sawfly. if you can avoid spraying things, that's best, but you also need to be aware that there are things that can impact your apple crop, and you may need to spray either right before full bloom, or in the case of fire blight, sometimes you need to spray during full bloom.
And what would the option be for fire blight? If you know you've got fire blight in your orchard, some of the trees have been hit, you can see that it's going to spread very easily, perhaps because the weather is It's damp or windy or whatever. What would you spray on those open blossoms to protect your trees from fire blight?
Sure. there's, a number of options. now, we talked about copper during dormant. There are copper sprays that you can apply during bloom, but they're not the same copper formulation that you would use during the dormant season. So they're going to be safer to use against the flowers.
and the copper itself is a bactericide. It helps to reduce the bacterium that are on the surface of the flower particularly, but on the plant overall, and can reduce the potential for infection. Bonide makes a copper spray, which is a copper octanoate, a 10 percent solution, and if you used according to label, it can successfully reduce your chances for getting fire blight.
another product that I like to use, and it's, the commercial name is Double Nickel. There are a variety of off the shelf products. but Double Nickel itself is a combination of two Bacillus organisms. Bacillus subtilis, otherwise known as Serenade, and Bacillus amyloliquefaciens, which is known by a number of different trade names.
But the interesting thing, even though it's considered to be a fungicide, those two Bacillus species are bacterial suppressants. So they may not kill the bacteria outright in the way that copper will, but they'll reduce the ability of that bacteria to grow and be successful on the surface of the plant.
And so what I like to recommend and what I usually do, is that if you've got a potential for fire blight infection is to apply a light rate of copper and a light rate of these Bacillus organisms to help reduce the Erwinia bacteria that's on the surface of the plant. There's also some other more biologically driven options that are out there.
One is called Blossom Protect. And these are yeasts and beneficial fungi, which for all intents and purposes, you're spraying onto the tree, they'll grow just like any other type of, microorganism will, but they're beneficial in that they can act as bacterial suppressants in some cases, but they can also out compete, territorially, on the surface of the plant so that the Erwinia, just doesn't have a chance to ever grow to any dangerous levels.
Gotcha. I've got a few questions here. I'm just going to check with Gary in the studio. Gary, is it okay if we go a few minutes after? Absolutely. Sure. just because I see our time is ticking away, but if you're okay, Mike, we're going to Our show will go on a little longer than usual so we can cover everything.
Wonderful.
[00:39:18] Resources and Listener Questions
So we have an email here from Chuck. Chuck says, Hi Susan and Mike, does Mike have any information online such as a website we can go to? Happy New Year to you and your families from Vancouver, British Columbia. Thank you, Chuck. what would you say to Chuck about resources? yes. I do have a website, knowyourroots.
com, and that's knowyourroots with one R. so there is a website there. There's not a lot of, Information posted there. My wife and I are working on revising the website so that we can have more downloadable PDFs and that kind of thing. But the best way for anybody to really stay in touch with what's going on in the field, the changes through the season, recommendations, that sort of stuff, is to contact me directly.
And I can get them to, I can get them signed up or subscribed to my newsletter, which follows the season, and has, there's some opinion stuff in there, but most of it's horticulturally oriented, so people understand, what's going on out in the field and what they can do to deal with issues, in their backyard.
And also, everybody, Mike is going to give me a PDF, that I can put on the promotion for this show. So once I, put the show online as a podcast, I'll make sure the PDF is there for you guys to download, which has some extra information. we've got an email here from Dawn. Excellent advice today.
Thank you. When planting new apple trees, are any pesticides needed at the beginning to prevent any diseases as a preventative measure? And then Dawn says, Portland, Oregon loves you. Happy New Year, Dawn. We love you, Dawn. Thank you.
yes. a typical way to spray is that you don't want to wait for problems to arise because then you're really dealing with a reactive approach. Now, there are some insects and certainly some diseases where, you don't want to be too trigger happy and going out and spraying because, you can't sleep at night or whatever, but you certainly in some cases do want to be ahead of the curve, scab would be one of those cedar apple rust is another which is very important and probably more in my in our neck of the woods is actually more important than apple scab to be in front of. And so from a preventative standpoint, diseases are probably the most important thing, because once you start to get those infections occurring, they can start to spread within the tree, between trees, to your neighbor's trees.
And you need to be ahead of that. But you also don't want to just blindly spray on a weekly basis because the pressures are not the same throughout the season and the pressures certainly are not the same from day to day or week to week. So understanding the life cycles of diseases can better guide your decision making when it comes to preventative sprays.
with insects, it's a little bit different because you don't really, you don't have the same potential to prevent outbreaks. And we did talk about dormant sprays. Oils can be a good way to help reduce populations and prevent that. Codling moth, in season, is one of the bigger, larval pests of apples.
It's known throughout North America. it's particularly bad In the Pacific Northwest, Washington State has a huge problem with it, and even though we know it in New York, our problems don't compare to what Washington State has. And from an organic standpoint, there are some preventative sprays that you can spray for codling moth, which are very effective, and they involve the use of a granulosis virus.
And the granulosis virus is very specific to, and it's something any consumer can buy. You could buy it from ARBICO Organics online, or, I'm not sure if Bonide has a similar one, but ARBICO I know does sell, and some other online sites, sell this granulosis virus. But it's very specific to codling moth, so it won't have any impact, say, on monarch butterflies, or other beneficial larval species.
used appropriately in a preventative way can keep codling moths from being an issue in your orchard. in some cases, yes, you can. There are preventative measures, but in a lot of cases, definitely want to be aware of what the life cycles are so you're treating at an appropriate timing.
But in some cases, you may want to wait until you start to see the first insects before you treat for them. Okey-doke.
Mike, oh my goodness, we have talked about so much so far. We talked about dormant sprays and we talked about blossom time sprays. Before we dive into growing season sprays, we've got another email from Aldo, who is from Toronto and Aldo says, if you spray during the growing season and it rains either the same day or the next day, do you need to respray after the rainfall?
That's a great question. The answer is, it depends. most chemicals that you're going to spray, whether they're consumer, over the counter, or commercial, are formulated to withstand a certain amount of moisture and rain. And typically, Unless you're getting more than an inch of rain, or if the rain, maybe it's a half an inch of rain and it's coming down just in sheets and whatnot, typically most of your sprays will have a residue through and protect up to and through maybe an inch to an inch and a half of rain.
So if you just get a little shower, a tenth of an inch of rain, or whatever, a nice gentle summer shower, chances are that you do not have to reapply. Now, part of that is, is that if you also want to make sure that the spray has about two hours of drying time so that it fixes appropriately to the leaf in the tree.
But if you get that fixing time, that dry time that's required, and you don't get excessive rainfall, or excessive rain conditions, your spray should be good through about an inch and a half of rain. Great. Okay, and we have an email here from Bev. Bev says, Hi Susan, this is Bev listening from Hornpain, Ontario.
Love the show. Thank you for bringing us this interesting and informative topic. Happy New Year. Thank you, Bev. Oh we've got another one from Tara. Hi again Susan and Mike. These sprays, are they available in Canada? Bonide, copper octanoate and Bacillus organisms.
then she says black knot infestation during blooming times. Same type of spray. What about antibiotics, such as tetracycline? Thank you again. Wonderful topic and thank you so much for organizing this podcast. And that's from Tara in Aran, Ontario. So Tara's got a good few questions, so we will go through a couple of them quickly.
are these sprays available in Canada? I'll just answer this part. We may not have Bonide here, but we do have a lot of the sprays. They just are under different names. So we do have copper sprays. We do have Bacillus sprays. I don't know if you want to add something to that, Mike? No, I don't. There are so many, I guess I'll add a little bit, is that there are so many different branded products out there that It's important to know what the, active ingredient, the actual, knowing that it's copper octanoate.
I might not be able to find the trade name, but if you're looking for that active ingredient in another product, you'll probably find it. And most of these are innocuous enough. And even though Canada has its own laws regarding, chemical registration and labeling, that I'm 99 percent sure that they're going to be fairly easily available in Canada, if not under one trade name, then under another. And also, Tara, I want to say to you and to all the listeners, if you guys can hang in there about three months soon, I'm going to have an integrated pest management course go live on my website at orchardpeople. com slash workshops.
So we are going to go into so much detail about all these things in that. If you're on my mailing list at orchardpeople. com, you'll find out. soon as the Integrated Pest Management Workshop goes live. the other questions were black knot infestation during blooming time. Should she spray for that?
Black knots are very interesting fungal diseases. It doesn't infect all stone fruit. will infect plums, to a great degree. You'll occasionally see it on some other stone fruit, but mostly it's just going to be a problem on plums and prunes. There aren't any, and this even is on a very conventional commercial scale, there aren't any good fungal products, that you can apply that are going to give you a hundred percent assurance that you're going to be controlling it.
But what I do know is that the period where the infection takes place for black knot, is when the shoots after they've grown a few inches in early spring, But before they started to develop that woody exterior bark, the tissue has to be green, in order for the infections to occur.
And so if you can apply some copper, or even some sulfur at that time, and that'll give you a modicum of protection against it. But the best protection against black knot is that if you see it, just cut it out and either throw it away or burn it. because if you don't have the inoculum, you can't get the infection.
And because there's so few effective, there's almost, there's no effective, 100 percent effective chemical controls. but because, there's just Not a whole lot you can spray for it. Sanitation and cultural techniques are the most important thing you can do. So also we'll do just another quick comment about her last question, which is what about antibiotics such as tetracycline?
There are a number of antibiotic products that are out there. The big problem is that whether we're you know, it's not just in agriculture, but in society in general we're running into some real problems with, antibiotic resistance, and particularly with something like streptomycin, which is commonly used in conventional agriculture for the control of, fire blight.
there's, oxytetracycline, which is also important, but these all are related to human, antibiotics, and the more we use them in the environment. the more it's going to drive up the resistance of bacteria, both for humans and animals, but also for, for fruit trees. There is one conventional antibiotic that is not related to any human, antibiotics, and it's called Kasugamycin, K A S U M G A M Y C I N.
it is a conventional product. you would have to have a license to be able to get it. but it is, from that perspective, it's safer to use. but typically I'm not recommending antibiotics except in emergency situations just because of the impact that they're having on resistant bacterial populations.
Oh, Tara, for those great questions. So now, I would say, Mike, we have about seven minutes left.
[00:51:50] Summer Sprays and Pest Control
let's talk about summer sprays. When we're talking about summer sprays, this is when you've got leaves on the tree, the fruit is starting to form. Can you give me a list of a few of the sprays that people might consider at that time of year?
Just to frame it a little bit, the first 10 to 12 weeks of the season, so from dormant until petal fall, are when we're seeing everything start to waken up and be present in the orchard. After petal fall and during those initial fruit, growth stages is when we're starting to see more of the summer insect and diseases that come out.
now, they're going to be different than the early season insect diseases. Some will be the same. but the intensity from an organic standpoint tends to go down a little bit. You still need to be vigilant, but it goes down a little bit and you can be fairly regimented in your approach. I already mentioned granulosis for codling moth.
That's one product that could be used. DiPel, or any Bacillus thuringiensis product, can be used to help control other larval organisms like ob obliquebanded leafroller, green fruitworms, oriental fruit moths, codling moth to some degree. and then there's also Entrust or a spinosad insecticide, which is also an important part of that overall rotation.
And I think when those are used in conjunction with a kaolin clay product like Surround, they can provide a very robust insect control. program and keep everything at fairly low levels. when you get later into the season, and again, depending on where you are, it could be mid July to early August, you're going to see something, come out called apple maggot fly, and those can be controlled organically using red sticky spheres and lures and just trapping them out, but Entrust or a spinosad insecticide and surround will also keep any potential apple maggot problems, at a fairly low level.
one final product that's out there are the pyrethrums or pyrethroids. Pyganic is probably the most common or popular of the organic pyrethroid products that are out there. they tend not to be as powerful as spinosads, but they can, when used in a rotational perspective, also provide a lot of protection against some insect pests, aphids, leafhoppers, that kind of stuff.
and then from a disease control standpoint, unless there's some really, unless there's specific issues that somebody is dealing with, again, I go back to the Bacillus products plus a copper every 10 to 14 days throughout the growing season, just to provide some fungal protection. So a lot of those products we talked in the beginning, like the copper, you have to have the right type of copper.
You have to have the right strength. But it sounds like copper is one of those ones you can use throughout the growing season, if it's appropriate. because you've mentioned a few things. again, so is that the case that some of these ones, would you ever use horticultural oil during the growing season?
you could, there are some very, highly refined horticultural oils, one branded product is called JMS Flowers, I believe they're out of Florida, but it's fairly common on the market. It's a very clean, horticultural oil that doesn't have the potential for phytotoxicity, again, unless it's misused.
But it can provide some benefit for piercing, sucking insects like leafhoppers and aphids and mites. You can get some control with it during the summer. horticultural oil, a refined horticultural oil or a Stylet-Oil as we call it, can be also used in rotation with those other products. Mike, I gotta say, thank you so much.
We have, during the show, we've, covered a lot of stuff, to give people an idea of, for instance, the importance of dormant oil sprays, which is when we think we should be putting up our feet and relaxing. That's time that we should also be doing more work on our trees and also just to get a big picture of what is involved in spring.
So I really appreciate you being able to touch upon this topic.
[00:56:31] Conclusion and Additional Resources
So again, let's tell people how they can get more information. I am going to have a pdf on the link for this show on orchardpeople. com, if you go to orchardpeople. com slash podcasts and you find this show, there will be a PDF from Mike with some more information.
Are there any other resources you would suggest Mike to help people if they want to create their own spray schedule that works for them and the problems they have in their orchard? Sure. again, my newsletter is a really good resource. I also have that one document that I sent you is part of a larger course, offering that I have, which is not all about insect and disease management, but there's some other things in there that might be useful to people.
I would say that any, especially Michael Phillips's first two books, are very helpful, in that regard for growers who are interested in organic and especially holistic, apple growing, from a more sort of academic approach. most land grant universities and given that I'm a stone's throw from Cornell, I lean on what they publish, but they do have a Tree Fruit Guidelines publication that's revised and released every year prior to the start of the season.
The first part of that book has some really good foundational stuff, just about IPM, spraying technology, etc. And the second half has even though it's not a recipe per se, it's a list of materials that are available for different insects and diseases. Now it's more oriented to the commercial growers, so there's conventional materials in there, but they're also including a lot of organic materials as well, in their guidelines as well.
And then lastly, Cornell, even though it's gonna be revised over the next year or two, but there is a free online organic apple growing publication that Cornell published about 10 years ago. It's also a really good background resource. Now, it doesn't have up to date information on sprays and stuff, but it gives good information on varietal susceptibility, rootstock susceptibilities, et cetera.
so for the beginning organic grower, that's also a good place to start. and then there are a number of other books that are out there, but those are my go tos when people want to know, how do I get started with organic orcharding. But that's where I point them. Wonderful, and also I want to remind everybody I have courses at OrchardPeople.
com and I am so excited to be launching the Integrated Pest Management course soon. So there will be that for you as well.
So Mike, thank you so much for coming on the show today.
We'll have to have you back. We'll talk about lots of different stuff with you next time. Okay. Thank you so much. Thank you. That was Orchard consultant Mike Biltonen of Know Your Roots in Finger Lakes, New York. Now we're at the end of the show and I would love to ask you guys a huge favor. If you like this show and if you're a regular listener, I would love it if you could rate or review the show on iTunes, Stitcher, iHeartRadio or whichever podcaster that you use to get your podcasts.
That would be so helpful for me. There are so many podcasts out there. So shows that have been highly rated, they'll be more likely to be found by new listeners. So I'd love it if you could rate the show on iTunes or your favorite podcaster, podcatcher. Thank you so much for your help. And that is it for today's extra long and extra powerful episode of the Urban Forestry Radio Show.
I hope you enjoyed it. If you want to listen again or download other episodes, you can find them. At podcast.orchardpeople.com. If you want to learn about my book, go to orchard people.com/book. And if you're interested in online courses, go to learn.orchardpeople.com . You've been listening to the Urban Forestry Radio Show.
This is Reality Radio 1 0 1. And I'm Susan Poizner from OrchardPeople. com. Thank you so much for tuning in. Happy New Year everybody. And I look forward to digging into lots of new fruit tree care topics with you guys all next month and next year. Thank you so much. Happy New Year, everybody.
You've been listening to the Urban Forestry Radio Show on Reality Radio 101. To learn more about the show and to download the podcast where I cover lots more great topics, you can visit orchardpeople. com slash podcast. This show is broadcast live on the last Tuesday of every month, and each time I have great new guests talking to me about fruit trees, food forests, and arboriculture.
If you're interested in learning more about growing your own fruit trees, or just about living a more sustainable life, Go to OrchardPeople. com and sign up for my information packed monthly newsletter. If you like this show, please do like our Orchard People Facebook page.
Thank you so much for tuning in. It's been wonderful to have you as a listener and I hope to see you again next time.
Thank you for listening to the Urban Forestry Radio Show with your host Susan Poizner, right here on Reality Radio 101.