Matthew Whiting, WSU Professor describes nearly two decades of research using a total systems approach for developing and adopting automation and mechanization in the production of fresh market quality sweet cherries. This presentation was part of the Webinar “Ensuring Premium Blueberry and Sweet Cherry Quality” organized by Lisa Wasko DeVetter and Carolina Torres, November 3, 2023.
Text Transcript and Description of Visuals
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| Okay, super. Thanks very much. Appreciate the opportunity to join you this afternoon or this morning, wherever you’re connecting from. I’m Matthew Whiting. I’m with Washington State University. I’m in the Department of Horticulture. And as we indicated in the short flyer and advertisement for this webinar, I’ve been working in this area of mechanization and sweet cherry production for nearly two decades now. So a lot of material to get through. | Title slide. Presentation title: Opportunities for mechanization in sweet cherry production. Presenter information: Matthew Whiting. |
| I’ll share with you, I think, just some of the highlights and opportunities that we’ve identified in abilities to incorporate mechanization. This really comes from a key point here. As I travel around the world and visit with different cherry farmers, the concern that rises to the top of their list is pretty consistent now. It’s labor availability. In other words, securing sufficient skilled harvest labor, pruning labor. And it’s the cost associated with that labor force. This is a photo I took a few years ago from Chile. An exciting time, of course, as the sun’s rising and ladders are getting organized and heading out to pick some fruit. | Slide titled “Growers number one concern: Labor availability and cost!” contains an image of orchard workers standing in a group outside of an orchard at sunrise. Many ladders are visible next to the group. |
| So understanding this, when I thought about strategically planning for my research program, it really came down to a longer term goal of improving production efficiency. And that, of course, comes down to the simple fact that traditionally cherries have an extraordinarily high labor requirement per hectare. And that’s basically because we used to have very big trees and, relatively speaking, small fruit. And so we’ve actually, in very simple terms, thought about reversing that situation, trying to have smaller trees and large fruit. | Slide titled “Improving production efficiency” contains text noting the high labor requirements in cherries, and bullet points listing the approaches taken to improve efficiency: orchard systems, and mechanization. |
| And in order to improve production efficiency, we’ve taken a two-prong approach. For the purposes of today’s presentation, I’m really not going to get into orchard systems at any length, and I’ll spend much more time focusing on the automation and mechanization opportunities, although it goes without saying that orchard systems are fundamental to the adoption of mechanization and automation. | |
| Touched very briefly on some of the interesting systems that So I just wanted to touch very briefly on some of the interesting systems I’ve seen over the years for sweet cherries. It is a crop among the tree fruit crops that is still pruned and trained and managed to so many different architectures. And here are just two examples. | Slide titled “Sweet-Cherry Orchard Systems:” contains two photos of different orchard training systems in cherries. |
| On the photo on the left, you’ve got a central axe architecture. And then an incredible amount of effort going into notching and scoring in order to induce lateral wood off of that vertical axe and so now your fruiting structures or your fruiting wood now becomes horizontal or in many cases below horizontal spur wood. And the picture on the right is another modern, relatively modern sweet cherry orchard that has a vertical axe but only for about 30 centimeters after which of course with the repeated dormant and summer pruning in order to create this bush style architecture now the farmer is growing their cherries on nearly vertical wood. | A red line is drawn on the vertical axe of each tree. Blue lines are drawn on the fruiting wood coming off of the central axe. |
| So these two systems just illustrate the complexity and the diversity in sweet cherry training systems that you’ll encounter around the world and that growers still consider today as they’re establishing new orchards. The webinar format doesn’t really allow me to ask questions clearly of the audience, but maybe a rhetorical one here. Which of these systems do you think is suitable for the future? | |
| And, well, I’ll tell you what my opinion is. It’s certainly not the one on the left for many reasons, which we don’t have time to get into today, but neither is it the one on the right. For many reasons, again, and probably fundamentally for the same reasons, I would not recommend either of these architectures. | A no symbol appears over both of the orchard training system photos. |
| This is a photo I’ve taken from Olsen Brothers’ wide trellised UFO block. This is probably a five-year-old photo now, but it illustrates quite clearly our vision. Compact fruiting wall systems that have repeated units that have simplicity in their pruning and training. But at the end of the day, the most important attribute we’ve been advocating for in thinking about new cherry orchards is the ability to incorporate mechanization and automation. And when we transform orchards from those previous two structures or any others that are three-dimensional and complicated, you lose or you lack the ability to incorporate relatively simple mechanization automation tools. | Slide titled “Our Vision: compact fruiting walls” contains an image of a cherry orchard which has been trained so that the trees are vertical and slim, forming a thin wall of trees. |
| And so that is the limit of my conversation on orchard systems and I’ll now spend the rest of the time talking about opportunities to mechanize or improve production efficiency for sweet cherries and you can see here if we begin on the left in the dormant season through flowering and harvest and then leaf drop in the fall, we’ve looked at opportunities for mechanical pruning in the dormant pre-harvest and post-harvest windows we’ve been looking at mechanical thinning, mechanical or artificial pollination, and ultimately we’ve been spending a fair bit of effort on mechanical harvest. | Slide titled “Opportunities for mechanization:” contains a horizontal sequence of six stages of cherry development. Labeled arrows point to parts of the sequence in which pruning, thinning, pollination, and harvest occur. |
| I want to begin with pruning because it is generally speaking it’s the second greatest expense for farmers behind harvesting and yet as you watch Trino prune this sort of modified steep leader architecture you’ll recognize quite quickly that pruning is far more difficult than harvesting. There are far more intricate and system-specific cuts and operations that need to be made. Of course, when you’re harvesting fruit, it doesn’t really matter the architecture that you’re in. That motion or that action, of course, is the same. You reach out and you grab a cluster of cherries and put them into a bucket. | Slide titled “Pruning” contains a video of an orchard worker pruning a cherry tree with pruning shears. To the right of this is text noting that pruning is the second greatest expense and is more difficult than harvesting. |
| I’ll skip ahead just to hit the highlights here. This is a 71-second video. And Trino makes 66 cuts. So he’s making about one cut per second. Of course, all of these cuts he’s making now are from the ground. He will, of course, have to come subsequently and prune the upper portions of that tree. But the somewhat rhetorical questions are, as you, as growers, are thinking about growers or as managers, what are the rules? How easy would it be to take a new crew and describe to them how to prune this orchard successfully? | The video continues to play. Text appears on the slide outlining the number of cuts made in the video and the number of cuts per second, as well as questions on pruning rules, follow up, and the ability to mechanize. |
| The second thing I wonder about is the ability of a manager to follow up, to understand how successfully the pruning crews are working. Are they making the right cuts? Are they making mistakes? How easy is it to determine that or answer those questions for yourself? And then lastly, of course, and this is the emphasis that we’ve been focusing on here, is the ability to mechanize that process that you just saw. Of course, I would suggest that it would be extremely difficult to mechanize those types of cuts that Trino has made in there. | |
| And this actually was in large part the motivation for developing of more efficient orchard architectures. And I’m just sharing with you here an older illustration of the UFO system which we developed at WSU years ago to be configured either to vertical walls, as you see in this depiction, or it can also be configured into Y trellis or V trellis walls as well. But the fundamental key here is that we’ve developed and worked it down to two simple pruning rules, for the most part. | Slide titled “Efficient orchard architecture” contains a diagram of the UFO system of pruning and training, with branches flattened against the trellis wires, and fruiting wood growing vertically. Text below this outlines the pruning rules of this system. |
| The first one is that you renew the largest uprights with stub cuts. Typically that’s done late, late dormant season, even early spring to renew that excessively vigorous or no longer fruitful wood with options of vertical new shoots to replace the wood. And then the second one is illustrated throughout here where cutting off lateral shoots. | A red circle is drawn around a section of the upright shoots. The shoot closest to the trunk has been pruned to make room for newer shoots. |
| And so that works very well for pruning crews, actually. They’re quite efficient in pruning and able to handle those relatively simple rules. And yet we also began to think then, if one rule is simply to cut off lateral branches, couldn’t we accomplish that mechanically? And this is a short video of work that we did years ago now with our first attempts at mechanized pruning in a vertical UFO orchard. | Slide titled “Mechanical dormant pruning in UFO:” contains an video of a mechanical pruning mount on a tractor cutting branches as it drives down an orchard row. Text below this outlines the benefits and drawbacks of this method. |
| This is using a series of seven circular saws and again all we’re doing here is pruning rule number two for the UFO, cutting off all those lateral branches. This is a dormant pruning and with a series of these large circular saw blades you can see that it’s quite fast. It’s limited really by the speed of the tractor. The uniformity is reasonably good, there’s a very pretty compact wall of blades there and it’s pretty simple to do. | |
| You know, driving the tractor versus carrying a ladder and a pair of loppers. Of course, on the downside, you can see a few there. It’s non-selective. If there is a branch in the cutting path, it will be removed. We’ve often found that it’s difficult to get very close to that vertical wall or close to the leader. And there are persistent questions related to the transfer, the potential transfer of diseases from using these mechanical approaches. | |
| When we studied this process of pruning by hand versus pruning by this machine, my postdoc and I found years ago that this is 13 times faster than hand. So it’s not that it’s a 30 or 50% improvement. It’s 13 times faster. | Text appears over the video noting that the mechanized pruning is 13x faster than pruning by hand. |
| We’ve looked subsequently at different opportunities for pruning. This is a photo of a sickle bar mechanical hedging system that can actually prune it really at any angle within the canopy here we’re doing some post-harvest hedging and in a vertical UFO block some work at a graduate student Jackie Gordon did with me again almost 10 years ago now. | Slide titled “Postharvest hedging in UFO” contains a photo of a tractor mounted mechanical hedging system. |
| But our studies here were looking and comparing the machine pruning versus hand pruning over a few years because growers had questions and concerns about effects of machine pruning on yield and quality of fruit. And so we set up these comparisons where there was hand pruning as a control in both years, machine pruning in both years. And then our third treatment was machine pruning in year one, machine pruning in year two, followed up with hand pruning. | Slide contains images of hand pruning and mechanical pruning in a cherry orchard, as well as text noting the pruning methods used in the study, as outlined in the audio. |
| And in actual fact, over the both years, we found that that machine pruning process was even faster than the first one. On average, it was 28 times faster for someone to drive a tractor and do three passes per row and mechanically hedging those trees. | Slide titled “Postharvest mechanical pruning” contains an aerial image of a cherry orchard. |
| And a visual way to represent those data are that if you had to prune manually, you would be able to prune that much of the orchard, but using the machine, one person could prune almost 30 times more of the orchard in the same amount of time. So we do see tremendous potential to improve production efficiency with mechanical pruning processes. And again, these really are only considered adoptable technologies in these fruiting wall architectures. | A yellow line labeled “Manual” appears lengthwise over one of the orchard rows. A red box labeled “Mechanical” appears over around 30 rows of the orchard. |
| So now what we’re thinking is that in the first year, one could do fully mechanical pruning as a post harvest approach, followed up in the second year by a fully mechanical pre pruning and then a follow up by hand pruning. And I think that one could get into this process repeating this every year. Our preliminary economic data showed that you really a grower would only need about 24 acres in order to pay off or get the economic benefit from purchasing one of these hedging systems. | Slide contains 4 rectangles labeled with years 1-4. Years 1 and 3 show full mechanical pruning, while years 2 and 4 show a mix of mechanical and hand pruning. |
| Where we’re going into the future with this, as we’ve simplified pruning and training decisions, of course, is towards robotics, which may not surprise you. So I’m working with colleagues at our Center for Precision and Automated Agricultural Systems to look at the potential for robotic pruning in sweet cherries, as well as apples, as you can see here. | Slide titled “Robotic pruning systems” contains a video of a robot pruning individual branches from a tree. |
| And these processes are pretty straightforward in the sense that they’re comprised of three key elements, the first of which is vision. The second is planning the path or how to approach and move towards the target. And then what are you going to actually do when you get there? So in this example, it’s a pneumatic pruning head that’s working. | |
| In this example, we’re using that same UR5 arm with six degrees of freedom. Here is the vision system mounted on the on the end of that arm. And then we’ve got a simply an off the shelf battery powered pruning head here for actuation. | Slide contains two images of a robotic pruning system being tested in an orchard. |
| And this is an example from last winter of where we were able to use this robotic pruning system to actually go out into a UFO orchard and make a pruning cut. Seems pretty simple as you look at it in this video, but there was quite a bit, of course, that went into actually being able to accomplish that. And work is continuing in this area over the next few years. | A video appears on screen of the robotic pruning system cutting branches in an orchard. |
| Okay, I wanna touch very briefly on thinning. We’ve done a lot of work over the years with crop load management in cherries and bloom thinning. | The slide “Opportunities for mechanization:” reappears on screen. A red box appears around the word “thinning”. |
| We’ve also been working on thinning in apples, but we’ve been testing the system that you see here as a potential for robotic thinning. In this case, it is functioning in an apple orchard, but it has those same components. There’s a camera that’s finding clusters of flowers It’s extending an arm approaching the clusters of flowers. And then the actuation or the end tool is simply a series of very short nylon cords that spin at high speed in order to physically just knock the flowers off or remove a portion of those flowers. So we’re using this in apples. We’re also using this in cherries or get high densities of flowers in, again, in these planar systems. | Slide titled “Robotic thinning studies” contains a video of a robotic thinning system in a blooming apple orchard. |
| We’ve also spent a fair bit of time looking at the potential for what used to be called mechanical pollination, but we’re really just calling just a supplemental artificial pollination. | The slide “Opportunities for mechanization:” reappears on screen. A black box appears around the word pollination. |
| And that work is based upon applications of a liquid pollen suspension using electrostatic spray systems. As you can see here, this is a machine built by on-target spray systems. And in this tank, we have a pollen suspension that we will drive through the orchard and then spray out those pollen particles at various stages of flowering. So we’ve looked at this for several years, looking at the rates of pollen to be applied, the best timings to apply pollen and the efficacy of the pollen. In some years, it doesn’t work because it’s not needed. In other words, when pollination is sufficient and successful by normal means supplementing your orchard with artificial pollination will be ineffective. | Slide titled “Supplemental artificial pollination” contains an image of an artificial pollination machine mounted on a tractor in an orchard. |
| In other cases, we’ve seen tremendous benefit from additional supplemental pollination through this system. Here’s just some quick results from some larger scale trials that were done on farms in California. This is with Bing. where one application of 30 grams of pollen per acre increased the yield by 23% compared to the untreated control. So this is about one ton per acre, about half a ton per hectare increase in yield, about 1,000 pounds. | Slide titled “Artificial pollination improves fruit set, Large scale trials – sweet cherry” contains a bar graph of the pounds per acre of Bing cherry yield for the artificial pollen treatment and the control treatment. Text below notes that there was a 23% increase in yield and an increase of 1 ton per acre for the artificial pollination trial. |
| A similar trial set up with coral champagne in California. In this case, the applications were split into two at 15 grams of pollen per acre. And in this case, a similar increase in yield, just about 27% or 1.7 tons per acre. | An additional bar graph appears on the slide showing the pound per acre of Coral Champagne cherry yield for the artificial pollen treatment and the control treatment. Text below notes that there was a 27% increase in yield and an increase of 1.7 tons per acre. |
| These numbers at the bottom of the bars are indicative of the size of the treated area that we collected data from. So 16 acres of untreated versus 6.3 acres of treated. So large, large plots. This is not individual branch type work. So we do see potential to increase pollination rate, pollination success with artificial processes. | The cursor points to text on the bottom of the bars indicating the acreage of the treated area. |
| I want to finish up and spend a little bit more time talking about mechanization of harvest, which has remained for some reason fairly controversial over the years and is yet to be adopted commercially. | The slide “Opportunities for mechanization:” reappears on screen. A red box appears around the word “harvest”. |
| We do understand quite clearly there are many factors that will affect harvest efficiency, and I’ve listed a few of those here. And from our studies over the years, we have found actually that the picker, picker themselves, has as great or a greater effect on harvest efficiency than any of these others. So in other words, if you can recruit and retain high quality, excellent pickers, you’re going to be much faster and more efficient than places that can’t. And another simple factor that we found is the presence or the absence of stems. | Slide titled “Factors affecting harvest efficiency:” contains a bullet point list of factors influencing efficiency including canopy architecture, fruit yield, environmental conditions, means of reimbursement, the rate of pay, the picker, and the presence or absence of stems. |
| We don’t have time to get into all of the work that we’ve done over the years, but we did some seminal work, again, about 10 years ago, looking at the effects of training system on harvest efficiency. For this work, we used the same people, a same picking crew, and we went around to 13 different commercial orchards in Washington State, and we studied how basically kilos per person per minute, their harvest rate, the speed of harvest in these different architectures. | Slide titled “Effect of training system on harvest efficiency (kg/min)” contains five photos of different orchard training systems. |
| You can see the numbers here 0.46 kilos per person per minute in an older system. An older system in the steep leader was it was a slight improvement. central leaders were faster still when we went to a KGB system, not quite pedestrian system, but they were even faster yet. And it may not surprise you that the Y-trellis UFO block had those same people were picking essentially twice as much fruit per hour or per day as they were able to harvest in the older architectures. So we can see that just simply by improving architectures and using a human skilled harvest crew, you can have a significant impact on harvest efficiency. | Red circles containing numbers appear over the different training system images. 0.46 for the older system, 0.52 for the steep leader system, 0.68 for the central leader system, 0.71 for the KGB system, and the 0.93 for the UFO system. |
| We are especially focused on this and have been and will continue to be because harvest accounts for 50, in some cases, upwards of 60% of your annual production costs for Washington growers. In my program, we’ve really been taking what I’ll describe as both a short-term and a long-term approach to addressing this. In the short-term, as I’ll show you, we’re looking at mechanically assisted or what we call shake and catch harvest tools and techniques. In the long-term, we still envision the potential for a fully mechanical harvest system. | Slide titled “Improving harvest efficiency” contains an image of workers in an orchard and a bullet point list outlining the benefits of improved harvest efficiency. |
| This is the prototype for that system that we’ve been testing here for about 15 years. It was originally designed by Dr. Donald Peterson, who is an Ag Engineer with the USDA in West Virginia. He shipped that system out to us again about 15 years ago, and we’ve been improving it and evaluating it in sweet cherry orchards in Washington. We have adopted a remote control operation of this unit. We’ve modified the end effector to be a vibrational end effector, but the key components remain the same. This is a catching conveyor, and then fruit are dropped and deposited into a bin at the rear through the collecting conveyor. | Slide contains a photo of a mechanical harvesting system containing two conveyer belts and a vibrating apparatus. |
| This system works extremely well in wide trellised architectures. And not only that, actually, fairly flat wide trellised architectures. Our test blocks were trained to about 55 degrees from horizontal, and that seemed actually ideal for this particular harvest system. This is clearly a longer term prospect, simply from the fact that there are not a lot of orchards in Washington that are trained or configured to a Y-trellis architecture. And for most of those that are, they tend to be fairly upright, which can damage the fruit versus a flatter Y trellis configuration. | Slide titled “Harvest systems and solutions” contains images of the mechanical harvesting system and of harvested cherries. A bullet point list to the left contains the issues and benefits with this system. |
| However, in our tests with this system, we have found a 50-fold improvement in harvest efficiency. In other words, if you had a picking bucket and a ladder and went out to an orchard to pick, even in this wide trellised orchard, versus sitting or operating this machine, you would pick 50 times the amount of fruit using the mechanized system versus the alternative approach, the traditional approach. So the potential to improve harvest efficiency is truly radical. As you can see in the photo on the right, this system does remove the fruit from the pedicel. So you get separation at that pedicel fruit abscission zone and you are harvesting stem-free cherries. | |
| This is a photo of the research orchard that I set up years ago in anticipation of adopting a fully mechanical harvest system. This is set up with Sila and Skeena on a 55 degrees from horizontal wide trellis UFO architecture. So again, all of these are uprights and originating from that permanent horizontal structure and that are renewed at the base. | Slide contains a photo of a Y-trellised orchard row. |
| In the interim, as I said, as a shorter term solution with an approach that could work in literally any architecture, we’ve been developing mechanically assisted shake and catch systems. And these are some photos from our old, old work where we were literally wrapping bed sheets on PVC posts and trying to catch the fruit that we would shake off the tree with one of these old gas powered steel units. When we did larger scale tests, we did find three to four fold improvement in harvest efficiency using these approaches. And again, we are harvesting stem free cherries. | Slide titled “Harvest systems and solutions” contains three images of different iterations of mechanically assisted shake-and-catch harvest systems. |
| Our prototypes have advanced somewhat to our using off-the-shelf battery-powered reciprocating saws, which we modify to add an end effector that’s usually an angled hook, something like this with rubber padding on the inside so we don’t damage the branches. We’ve looked at various configurations of catching frames In fact, we’ve got several versions that you could harvest 12 foot tall trees from the ground with an extended shaker and an extended catching frame. In this case, we’re actually collecting fruit in this tube and then transferring the fruit from the tube into the standard bin. So off the shelf battery powered systems for small localized shake and catch harvest approach. | Slide titled “Shake-and-catch prototype” contains photos of one of the prototypes with it’s component parts labeled. |
| I’ve mentioned that as we’re thinking about mechanized harvest, at the end of the day, we come to this issue of stem-free cherries. You’re seeing a photo here of where we conduct a larger scale trial. We ran stem-free, this happens to be Skeena, over a commercial packing line, had it sorted and stored. We’ve done years of work actually looking at consumer preference for stems. And the bottom line, from our experience of what we’ve seen is that consumers will absolutely purchase stem-free cherries, particularly actually if they look as good as these Skeena do. | Slide titled “Consumers will purchase stem-free cherries” contains an image of stem free cherries on the packing line. |
| And just one quick example of some of the consumer preference studies that we’ve run in collaboration with Carolyn Ross years ago. Simply put, which product would you prefer when consumers were offered cherries with stems or without stems? In this case, 44 percent said, I prefer cherries with stems. In fact, the majority said they prefer cherries without stems. | Slide titled “Consumer preference” contains a bar graph of the responses to a survey asking if consumers prefer stemmed cherries, stem-free cherries, both, or no answer. 55% of the consumers preferred cherries without stems. |
| And then the logical follow-up question is then, how much would you be willing to pay for stem-free cherries compared to cherries with stems? And here we’re finding that three quarters of the people surveyed said, it doesn’t matter, I would actually pay the same prices as for cherries with stems. There’s a few people who said, you know, I might buy them, but I want to pay a little bit less. And this is actually the population we’re very interested in. 8% of people said, I actually prefer that I would pay more for cherries that didn’t have stems, unknowing that they were harvested at such great efficiencies. | Slide titled “Consumer preference” contains a bar graph of the responses to a survey asking how much consumers would be willing to pay for stem-free cherries vs. stemmed. |
| One of our former collaborators, Chelan Fresh, has even looked into the potentials for and have these commercially available, this Cup O’Cherries, which is just indicative of a novel approach to marketing stem-free cherries. This is kind of what we’ve envisioned all along is that stem-free cherries would not flood the marketplace and be in direct competition in grocery outlets, but rather could become a specialty type product with specialty type packaging. | Slide titled “Develop markets for stem-free cherries” contains promotional images for the product “Cup O’Cherries” which is a cup of stem-free cherries. |
| So in conclusion, to think about future research efforts, I’m very supportive of transdisciplinary work that occurs at this intersection of biology and technology. As we think about planting new orchards and designing new orchards, we must prioritize high efficiencies. We’ve got, of course, to have the fundamental elements of quantity and quality of fruit, but I do want to re-emphasize the importance of thinking about potentials for mechanization and automation solutions to improve production efficiencies. | Slide titled “Future research efforts, Transdisciplinary work at the intersection of biology and technology” contains a bullet point list of three research efforts, as outlined in the audio. |
| With that, I’ll leave you with my email address if you have any questions that you can’t get to throughout the Q&A session this morning. Otherwise, thanks for your attention, and I look forward to answering questions you might have. | Slide contains the presenter’s contact information. |
| Next question. Do stems extend the shelf life? How about for export markets? That’s for Matt. | A Q&A moderator appears full screen in a video conference call. |
| No, I would argue that the pedicel or the stems and cherries actually decreases the shelf life. A lot of times buyers at retail or even mid produce buyers for retail make decisions based upon the quality of the stem, which is so independent of the quality of the fruit, of course, right? And stems deteriorated at a rate much faster than the fruit do. So you’ll see dried up terrible looking stems when the fruit quality actually could be quite reasonable. So no, the stem does not increase the shelf life. And it’s also one of the main factors contributing to pitting. So stem is actually a bad actor in post harvest for cherries. | Matt Whiting appears full screen in a video conference call. |
| Thank you. Next question for you, Matt. Is it possible to mechanize harvest of cherries with stems? | The moderator appears full screen. |
| Yeah, I’ll say maybe, maybe, maybe sometime in the future. For right now, actually, I’m not interested in that at all, because I’m very convinced in the systems that we have now in our ability to harvest stem-free cherries. There are two abscission zones, right? Between the pedicel and the spur, which you’re talking about, removing with the stem, and between the pedicel and the fruit. And towards harvest, if we have a well-developed abscission zone between the pedicel and the fruit, they naturally will release from that point. And when we have a well-developed abscission zone, there is no leaking of juice or tearing of flesh. It’s actually a wonderful quality fruit. So we’re really focused right now on harvesting high efficiency harvest systems of high quality stem-free cherries | Matt Whiting appears full screen. |
| Thank you. Any other questions? Even if you want to just, okay, let’s do, yes, they just came in. Okay. Is it possible for pitiless or pitless cherries in the future? | The moderator appears full screen. |
| Yeah, that one I’ll say also for sure it’s possible. Yeah. And there’s been some work done out by USDA scientists out east who are working on this issue, which is really looking at the endocarp, right? It’s the botanical term for that lignified pit, pit structure that protects the seed. So it is possible. They’ve looked at the genes that are involved in endocarp formation or lignification of the endocarp and looked at this in a different stone fruit species, but looked at it with plums. And they have developed those that don’t lignify the endocarp. So it’s still there, actually. Pitless? Not technically, no, but maybe more of an edible pit that wouldn’t be woody at any rate. But then you bring into question actually the role of the seed that would be inside. You would still need to have the fertilization, right? Which means you’re going to have a seed inside there, an embryo, an endosperm, which the pit protects. So that would still be there. But yeah, sure, it’s possible to have maybe an edible pit or what you might think of as a pitless cherry in the future. | Matt Whiting appears full screen. |
| All right. Thank you. Thank you. Next question. Is there any management that could promote the abscission zone development? | The moderator appears full screen. |
| Yes. Yeah, definitely. Yeah. We’ve looked at a wide range of commercially available cultivars and how suitable they would be for mechanized harvest based on how easily they come away from the pedicel. And there are tools and there’s plant growth regulator treatments that you can use to induce that abscission zone formation so that the fruit come quite easily from the pedicel they’re usually ethylene based PGRs, but yes there are programs that you can use to increase the ability to mechanically harvest cherries. | Matt Whiting appears full screen. |
| Okay, there’s two more questions. Let’s see if we can do it quick so we can move on but one of them is: What is the perception of stemless cherries for the Asian markets? | The moderator appears full screen. |
| Oh, yeah, I think it’s a good question. I think we, right now, I would say it’s not very good. The perception is that buyers in Asian markets, which are critical, I understand, for Chilean fruit, do not like stemless or stem-free cherries because they feel that the pedicel=l is somehow a direct indication of the quality of the fruit. And I think that just requires some education. And again, a different marketing approach, a different channel of premium packaging of beautiful stem-free fruit. And I will bet that there is a percentage, some percentage of the Asian market that would be happy to buy a high quality stem-free fruit. | Matt Whiting appears full screen. |
Link to YouTube video: Automation Mechanization in sweet cherries. Dr. Matthew Whiting
