UC Ag Experts Talk: Fuller Rose Beetle

Good afternoon everyone and welcome. Hello I’m Cheryl Reynolds with the UC Statewide IPM program, and welcome to the UC AG expert talk on Fuller rose beetle. Petr Kosina is here with me, also from the UC IPM program, and he’ll be running our polls and doing our troubleshooting and [fixing] any technical problems we might run into. Okay, and so now I’d like to introduce our speaker today: Dr. Beth Grafton-Cardwell. She’s a citrus IPM Specialist and Research Entomologist. Today, she’s speaking from the Lindcove Research and Extension Center on Fuller rose beetle. So Beth, I will turn this over to you and you can share your first slide. [Beth]: Okay, It will take me a few clicks here. There we go. So this first couple of questions were mostly to get you warmed up on how to use the equipment, and at the end we will have a 10 question quiz and Cheryl will be fielding. I don’t see the chat questions; she’ll be fielding those and she’ll sort of save them up probably for the end unless she sees something that she wants to dive [into] while I’m talking. So I’m going to go ahead and get started. I have about a 30-minute talk and I’m leaving time for the questions at the end that we’re going to ask you, and then there will be time left over for you to ask me any additional questions or gain clarification from what I have or have not told you. So today is all about Fuller rose beetle biology and management. The life cycle looks like this. Fuller rose beetle, or weevil, undergoes complete metamorphosis, which means that it has egg, larval, pupal and adult stages. What’s unique about Fuller rose beetle is that it does not need males to reproduce. It reproduces parthenogenically, like aphids do. Its life cycle takes about nine to twelve months to complete, so there’s just one generation per year. It is a small, gray beetle with a weevil-like snout, it’s about a half-inch long, and the adult is very slow-moving and is flightless. Adults feed on the foliage at night and they remain inactive and [in] protected places during the day, and they play dead and drop to the ground if you disturb them. The adults can live for an average of a hundred and ten days in the laboratory when fed citrus leaves, so they’re very long-lived. Fuller rose beetle eggs are very tiny, and they’re deposited by the female’s long ovipositor. So in the upper part of this screen, you see two females lying on their backs, and on one of them the ovipositor is extended, so you can see how long it is. And they like to take that ovipositor and insert it into cracks and crevices in the bark, and they particularly like under the sepals of, or the calyx button end of, the fruit. And that’s just a favorite place for them. They’re probably also laying them in curled leaves, and we also know that they lay them in sprinkler emitters. And when they do that, they can block up the emitters, and this leads to improper irrigation of orchards and increased costs [of] trying to find which emitters are plugged, and replace them. So that’s one of the main problems we have in California citrus. — Adults feed for about two weeks after they emerge from the soil, and then they begin to deposit eggs. The eggs are laid in clusters of ten to twenty at a time, and they’re covered with a white, sticky material. Each female produces anywhere between a hundred and a thousand eggs in her lifetime, and lays them over a three- to five-month period. And then after that it takes about two to six weeks for those eggs to hatch. So, [a] very long-lived animal, laying lots and lots of eggs, over a very long period of time. — The eggs hatch, and the first stage is this very tiny “neonate”—we call it—larva, and they wiggle around, and drop to the ground, and wiggle into cracks and crevices in the soil in search of tiny root hairs to start feeding on. So that stage is down on the ground. — The larvae are active in the first few inches to two feet of the soil, the larvae molt multiple times over a six- to eight-month period, gradually growing larger and larger each time they molt, and as they grow larger, they advance to larger roots, so they can feed on larger and larger roots. So they’re moving more towards the center of the tree base. Larvae reach about half an inch in length when they’re fully grown. Young Fuller rose beetle larvae are very small, and can only attack the tiny root hairs. In California, there’s no evidence that the feeding on the roots causes enough damage to warrant treatments, so we generally don’t consider them a pest—a root pest. However, if other pests and diseases, for example the bacteria that causes Huanglongbing, or Phytophthora, are attacking the roots or [if] other stress factors such as drought are present in addition to Fuller rose beetle, it’s possible the combination may cause sufficient root death to lead to tree decline or loss in production, so it could have a direct effect in combination with other factors. But generally on its own, it’s not that damaging. — When the larvae are fully mature, they produce anal secretions that help them develop an earthen cell in the soil. And there they pupate. So in the lower picture, you can see the larva and the pupa. The pupa resides in the soil for one and a half to two months before the adult emerges, and generally adult emergence is triggered by rain or irrigations. Fuller rose beetle adults chew the leaves of citrus trees at night, making characteristic chew marks or notches or serrations on the edges of the leaves, so that’s one good way to figure out if they’re in your orchard. Occasionally they eat the entire leaf, leaving only the midrib behind. The leaves with the heaviest damage are usually on lower branches and on water sprouts or suckers inside the canopy of the tree. — Generally leaf damage is not severe enough to affect yield or health of the trees. The exception to this generalization is when the adults attack the expanding leaf buds of newly grafted, top-worked trees. Feeding damage in this case can completely decimate the new buds. Another situation where significant damage could occur is when a young tree is planted in a mature grove and very large numbers of beetles concentrate their feeding on the new growth of that tree. — In this study we focus on Fuller rose beetle as a pest of citrus, however they also have been reported feeding on other horticultural crops such as cherries, persimmons, apples, stone fruit, avocado, potatoes, strawberries, and caneberries, as well as many ornamentals such as roses, Photinia, hydrangea, Hibiscus, azaleas and begonias. So they’re very much a generalist. — Fuller rose beetle was first reported in the United States in 1879 in California, And it’s now present in thirty states, and most likely it came from South America. — The Fuller rose beetle is currently found in North America and South America, in Europe, parts of Africa, Australia, Japan, and the Pacific Islands. It is not known to occur in Asia other than Japan. So, therein lies our problem, since a lot of the export citrus from California goes to Asia. — While California growers don’t consider Fuller rose beetle to be a pest of citrus, it has not been found in South Korea, and that country has considered establishment of Fuller rose beetle to be a phytosanitary risk since 2011. — Fuller rose beetle was an issue for exports to Japan from 1985 to 1998, at which time they discovered the beetle was established in Japan and the quarantine ended. South Korea has been searched, and there’s been no evidence that the beetle is in that country. — As methyl bromide use is reduced worldwide, there’s increasing pressure for California growers to reduce Fuller rose beetle populations in orchards. And we’ll talk some more about that. For many years, South Korea allowed methyl bromide fumigation at destination— you know, shipments of California fruit would arrive there, [and] if they found live eggs, they would simply fumigate it with methyl bromide. However, this method of disinfestation may not be available in the future. Most countries are trying to eliminate methyl bromide use. And so the expectation is that California growers fix the problem in California, before they ship the fruit to South Korea. — Now the problem with that is that Fuller rose beetle adults overwinter in larval and pupal stages in the soil, and they emerge every month of the year. Because in California, it’s not all that cold in the winter time. So obviously from this graph, the peak emergence in the San Joaquin Valley is June, July, August, September, October, but they can also be emerging any old time. So it’s very difficult to come up with a treatment that is going to eliminate them from California orchards. However, we can target the peak period in order to reduce their numbers enormously, so that there’s less risk of them arriving in in South Korea in the fruit. — So this graph compares emergence patterns, and this is work of Dr. Joseph Morris. Emergence patterns of the Fuller rose beetle in the San Joaquin Valley, in the coastal areas, and in inland Southern California. So [the] San Joaquin Valley is what we just looked at in the previous slide— that’s the blue bars. [In the] coastal area, because the climate’s a little bit milder, the emergence pattern is a little more spread out. And for some reason, in inland Southern California it’s sort of shifted right towards October [and] November. So peak [emergence] for the San Joaquin Valley is August, peak for [the] Riverside area is August and September, and for the coast it’s August and September as well. — So this is just to point out that it depends on where you live when that peak emergence is going to happen, and that influences when your management tactics might be utilized. — We’ll come back to that in a couple minutes. — So, biological control: Is there any biological control? Joe Morris looked at this over many years, he found a little parasitic wasp called Fidobia, and this wasp lays its eggs in the eggs of the Fuller rose beetle, but it’s out there, it’s doing some work, but not very much relative to the volume of Fuller rose beetle eggs that are out there. So it’s just not been something that’s rearable and releasable, and so biological control has just not been very effective. Not at the level you need for exporting citrus fruit. — There are many other general predators out there; when we’re out there looking at Fuller rose beetle populations in orchards we often see spiders working on them In the lower-right picture there you see a Fuller rose beetle that has been ripped in half, and the guts have been fed on. There [are] probably assassin bugs attacking them as well. So lots of predators out there are working on them, but again, they’re not reducing them low enough for export purposes. And I’m sure it’s difficult for them to prevent egg-laying under those calyxes, which are very protected environments. — So let’s talk a little bit about how you might go about avoiding rejections of shipments to South Korea—having them reject your bulk citrus fruit shipments. So step one is to look at the orchard, look to see if it has obvious signs of Fuller rose beetle, and if it does, don’t ship fruit from that particular orchard, because it’s going to be very difficult to reduce the numbers low enough that you’re going to have a perfect shipment. So we advise looking for those notched leaves, especially on the interior leaves of the tree, and looking for the fecal pellets or feces of the beetle, which are pretty characteristic. — We also recommend, let me start this video here… Here’s Stephanie—[I] didn’t mean to have volume on that, so ignore the volume— — Here’s Stephanie beating a tree that she’s seen some evidence of damage in the tree and she’s shaking it to see if she can knock some of the female beetles out. Because they’re flightless, once they’re banged onto that sheet they’ll just lay there for a while. So they’re pretty easy to count, so that’s a quick way to find out if there are beetles roaming around in the branches. — If you have, or if you think you have them in there, and you want to look for eggs, there’s a couple different ways to do it. You can cut a piece of fruit off and leave a bit of stem there that you can twist, so you can twist the calyx off, or—we’ll show you another method in a minute, but either way, fruit that has really tight sepals that are tightly, sort of glued to the fruit are going to be very difficult to look at, and they’re also going to be going to be less likely to have eggs. If you can find fruit that has loose, open sepals like the one picture on the right then you’re more likely to see eggs because that’s created a really nice crevice for that Fuller rose beetle to insert her ovipositor and lay the eggs. And if you want to be diligent, you can do like inspectors do and you can collect fruit from ten areas of the block, and look at five fruit per tree from each of ten trees and look at a total of five hundred fruit. That’s that’s a lot of work, but that’s a way to find out “do I have significant levels of Fuller rose beetle in the orchard?” — Here is Stephanie—again ignore the sound in the background, I didn’t mean to have the sound turned on—but she is prying up the sepals there with a little spatula, so then she can flip the fruit over and look to see if there are any eggs underneath. — Pretty tedious work, you’ve got to look at a lot of fruit sometimes to find those eggs. We’d be happy to train anyone who would like to see Fuller rose beetle eggs for real. — So step two to avoid South Korean rejections of shipments is, if you determine that your orchard has a load and no F.R.B. using all these previous methods, then you apply mitigations that the California Citrus Quality Council protocol has provided to you. And you can look on their website to learn more about that. But the basic regulations are skirt pruning, weed control, and two treatments applied to either the ground or the foliage; any combination, [it] doesn’t really matter. So I’m showing you basically the San Joaquin Valley methods, but you want to skirt prune because the animal can’t fly onto the tree. So if you skirt prune, the only way it can get to the tree is by climbing up the trunk. And then if you apply a ground treatment, and/or a foliar treatment, you’re either preventing them from getting on the tree or you’re knocking them out of the tree with insecticides. And you’re doing this in the June, July, August, September, October period, because the eggs laid in that period are the ones that are most likely to still be alive at harvest in January, February, March, April. So if you treat—well, we’ll get into treating too early versus too late. So let’s go through the methods first. So skirt pruning is 24 to 30 inches above the ground, and then you’ve gotta periodically through the season, check to make sure there aren’t any weed bridges. You would be amazed, these beetles would climb right up weed bridges and climb on trees. — Skirt pruning and eliminating weeds, by itself, is about 30 to 50 percent effective in reducing the number of beetles in the tree all by itself. Then we spent a number of years screening insecticides to see which ones kill adults. We looked at every insecticide basically registered for citrus. And I’m showing you part of the data, but you can see in the graph on the right that Movento and Sivanto weren’t very effective, but Actara, Exirel, Kryocide, Sevin, Lorsban, Agri-Flex, and Leverage were fairly effective in killing them and preventing them from laying eggs as well. So if we look at the table on the left, these are the rates that I used in these experiments. And of the many insecticides screened, this group were the best at killing adults and preventing egg laying. And if you want more information about rates, you can go the UC IPM [Pest Management] Guidelines for Citrus to get those details about application methods and rates. — Not all Fuller rose beetle-effective insecticides had or have maximum residue levels (MRLs) established, or have MRLs that are close to or lower than the South Korean MRLs. That means that there’s a risk that if these products are used close to harvest, the residues will be above the Korean MRL and the fruit could potentially be rejected. For example, when we first started this four or five years ago, the Sevin Korean MRL was 0.5 [parts per million]. That’s considerably different than 10 ppm [for the] US MRL. So there was concern that, “whoa if I use Sevin or Lorsban close to harvest, there could be residue levels above what [South] Korea accepts and if they test for those residues, they might reject shipment. Therefore the bulk of the industry started using Actara as their main control for the Fuller rose beetle for this purpose. At that time Exirel did not have MRLs established; now it does. So that’s a potential chemical. Kryocide works very well against the Fuller rose beetle, but it has never had MRLs established for any countries, so that’s problematic. So you can see that MRLs make a big difference on choice of insecticides. — So I said previously that skirt pruning and weed-block kind of things are about 50% effective. A single foliar treatment or a trunk treatment or a ground treatment of Brigade was about 80 to 90% effective, so very effective, but then when you add in two treatments you get up more to the 95% or higher level of efficacy, and so that’s why the recommendations came down to two treatments. — Okay, let’s keep going. Trunk or ground treatments are—the purpose of those is if there are eggs hatching and neonate larvae dropping down into the soil, or if there are adults emerging out of the soil, they’re going to contact those long-lasting soil insecticides, so that’s the purpose of ground treatment. And Brigade is only registered for ground or trunk; you cannot let it touch the fruit. There are no MRLs or even tolerances established for fruit [will be met], so it has to be a ground or trunk [application]. So that’s the purpose of doing those kinds of treatments, and those would be best applied early in that June-through-October period. Foliar treatments are really designed to knock adults out of the tree—basically kill them before they can lay eggs. And so those could be applied early or late, [it] doesn’t really matter. — There are currently no effective foliar organic insecticides to control Fuller rose beetle, and so if you were an organic orchard, and you wanted to ship to Korea, [you] would basically be limited to applying them to the trunk to prevent the beetles from getting access to the canopy in addition [to] skirt pruning. But because citrus bark is sensitive to that stickem, it would have to be applied on some kind of wrap and then it would have to be reapplied to make sure it stayed sticky and the beetles couldn’t get through it. But there—it is feasible to do this if that was desired. — Okay, I’m close to finishing now. I kind of want to back up a couple slides and just say that Joe Morris did a lot of degree-day work to show that it takes 650 degree-days for those eggs to hatch. [The] problem is we don’t know in the future what the degree-days are going to be. So these estimates of when to treat are based on—okay, eggs are laid in August, 650 degree-days later is going to be harvest—an approximate harvest time, [and] that’s why you’re treating them. If you treat too early, the beetles that emerge later don’t get affected by the residues, and so you get egg laying. If you treat too late, same thing. You’re missing the peak emergence. And a lot of the beetles that emerge a lot of the beetles that emerge in like, May-June, their eggs are already hatched by the time harvest comes. The really important part of the population control is the August through October portion. That’s the portion [when they are] most likely to be laying eggs that will still be viable at harvest. And that’s what the Koreans are looking at. They’re looking at when they examine fruit, [if] the eggs are hatched or dead they don’t really care, but if they’re viable, that’s when the shipment is rejected. So you’re trying to sort of hit primetime of egg-laying for eggs that will be viable during harvest. And it’s just really difficult. You notice back in this one, we did two treatments, and skirt pruning, and everything we were supposed to do, and we never completely eliminated Fuller rose beetle from our experimental orchard. Very very difficult, yet, imperfect control. So, what’s happening in the meantime? Several people, including Spencer Walse with the USDA and Sandipa Gautam with the University of California, are screening other methods—They’re trying to develop other methods. And Beth Mitcham is working with ethyl formate—not only to control Fuller rose beetle but other post-harvest issues. And they’re looking at Fuller rose beetle in the process. And the hard part is, Fuller rose beetle eggs are really, really tough. They have sort of a layer over them. And so, even looking at these new fumigants that we’re very excited about for bean thrips, for mites, for Asian citrus psyllid—[the fumigants knock] them dead really fast, really well. It takes much longer for much higher dosages to kill Fuller rose beetle eggs. So in the case of phosphine, bean thrips died within 12 hours. Fuller rose beetle takes five days [for phosphine] to kill them all. Propylene oxide—to our bean thrips treatment that would be a beautiful treatment. Fruit in, treated for two hours, fruit out. It takes 24 hours for Fuller rose beetle. And with ethyl formate [for bean thrips] it’s 1 hour, [rate of] 9 milligrams per liter, for Fuller rose beetle [it takes] 5 hours [and a rate of] 62 milligrams per liter. And the higher the dosage, the more likely you’re going to have phytotoxicity. So we’re just still really struggling with Fuller rose beetle in terms of coming up with a post-harvest treatment but that is the goal. [The goal] is to find a fumigant or some other tactic that would kill the Fuller rose beetle. Sandipa is now looking at the fact that this fruit is being shipped, it’s under cold treatment, and it may be that the combination of one or more of these fumigants in combination with cold treatment will give sufficient kill that it will be equivalent to all these treatments you are doing in the orchards, and we’d be able to eliminate those treatments. So that’s the goal, and that’s the lecture on Fuller rose beetle and I think it’s up to Cheryl and Petr. Are we going on to the questions now, the quiz questions? And then we’ll take questions from the audience. [Cheryl]: Yeah, I think we’re gonna go ahead and add the poll questions. Right now we just have one question from the audience. And maybe while they’re answering this poll question, I can ask that to you. [Beth]: Sure. [Cheryl]: Okay, so Sara asked, and it’s just for clarification, “when you mentioned two treatments, does skirt pruning count as one or do you need two sprays?” [Beth]: Two sprays. So it’s skirt pruning, plus two treatments. And any combination of those effective chemicals that are in the UC IPM [Pest Management] Guidelines is fine. Two ground, one ground, one foliar, or or two foliars, whatever. [Cheryl]: We do have one other question while we close out this poll: “Is there a concern of losing some of the effective neonic insecticides for these treatments?” [Beth]: By applying them twice a year, I assume is the concern. From a resistance management viewpoint, it would be smart to alternate Actara with something else, so that you’re not doing the two treatments of Actara every year because yes, that is gonna select for resistance, if not in Fuller rose beetle then in something else. I would say on the plus side, I think these Actara treatments, especially in the San Joaquin Valley, have been helping to keep the Asian citrus psyllid at bay because it’s very sensitive to that particular chemical. — [Cheryl]: Okay, I think we’re bringing up the results now. So Beth, you should be able to see the results. [Beth]: Yeah, I do. The question was “Fuller rose beetle is currently a very damaging pest of mature citrus trees.” This could be—some people could feel this, and it is an opinion, but I would say it’s false. It’s generally not a very damaging pest in mature trees. It’s just there and it’s feeding on roots and we normally, if we didn’t have South Korea issues, we would probably ignore it completely. Next question. [Cheryl]: Alright, so he’ll close this one out and bring up the next question. [Beth]: How many generations per year does the Fuller rose beetle complete? One, two, or three? — [Cheryl]: Okay, you should be able to see the results. [Beth]: Okay! 68% of you are correct. There’s just one generation per year. Really slow growing. Next question. — “What is the most important consequence of Fuller rose beetle infestations? Root damage, leaf damage, rejection of export shipments to South Korea, or blocking sprinkler emitters?” — [It] probably should have said “what is the most costly consequence?” (laughs) — [Cheryl]: And I do have a comment about the neonic question. [Beth]: Uh-huh. [Cheryl]: So they said, “Sorry, the neonic question was targeted more towards the elimination of these chemicals due to the negative effects on pollinator species like bees and butterflies.” [Beth]: Yeah, I’m fighting really hard to maintain registrations because they’re such important chemicals for citrus pest management. We have a good case in citrus, [because] bloom happens—with the exception of lemons—happens only one month out of the year, and so I think over time we’ll be able to maintain registrations by limiting treatments to certain months out of the year and that way maintain registrations. [Cheryl]: Alright. We’re going to be closing out this poll [and] bringing up the results. [Beth]: Ok, 94% of you answered the way I would, that rejection of export shipments to South Korea is the most costly consequence. If the shipments are rejected, it’s a loss. Okay, [next] question. [Cheryl]: There is a comment—somebody asked for the mite species on the current slide that you’re on? — [Beth]: Oh. I—that’s leftover (laughs) from another slide—that cut and paste… [Cheryl]: Okay. (laughs) [Beth]: But the mite species would be [those] that Australia is worried about, [including] Brevipalpus, which is flat mite, which are common in California, and some fungal feeders called Loria and Tarsonemus. What we’re trying to do is come up with a fumigant that will kill everything. — “Fuller rose beetle only feeds on citrus. Is that true or false?” — Okay, 97% of you are correct—Fuller rose beetle feeds on lots of different things, so the answer was “false.” — Next question. [Cheryl]: And while that one comes up, someone was asking, “Why is it called FULLER rose beetle?” [Beth]: Oh, somebody asked me that and Ben Faber even looked it up, and now I forget what the answer is. A man named Fuller discovered them. So, that’s my answer. But I think there’s more to this story. So if you’re really curious, contact Ben Faber. Okay, next question—”In the San Joaquin Valley, the three peak months for Fuller rose beetle adult [emergence from the soil] are…” June-July-August, July-August-September, August-September-October, or September-October-November?” [Cheryl]: Okay, we’re gonna bring up those results, and I do have a question for you: “Are there any post-harvest options for eliminating Fuller rose beetle adults and eggs?” — [Beth]: At the moment, no. Because the phosphine treatment for bean thrips, which just got registration, is only…I think it’s like a 12-hour treatment, and so it’s not long enough to eliminate the Fuller rose beetle. So at the moment no, there is no registered post-harvest treatment, but we’re working on it. Okay, the correct answer is July through September. That’s when the [peak happens]. So a third of you got it right. And the reason that question is important is, people are always asking me, “Is this June treatment I did or this November treatment I did for this other bug—does that work for Fuller rose beetle?” And we really have narrowed it down to, you need a June-July treatment, an August-September treatment or kind of into October, but you don’t want to go too late because that’s not going to help you [with the] problem. — “Fuller rose beetle is mainly a quarantine concern for shipment of California citrus sent to South Korea. What’s the best strategy to take if a grove has high levels of FRB?” Skirt pruning, weed control, and two insecticides? Methyl bromide treatment of fruit shipments in South Korea? Or don’t ship from orchards with high FRB? [Cheryl]: And there is a question. How did Fuller rose beetle get into the citrus orchards? [Beth]: It would have had to crawl, because they’re flightless. So whoever brought it here on whatever plant that [it] came on, it just grabbed it, adapted, moved, and because it’s polyphagus it can feed on a lot of different things. If someone were to bring it in on a rose or something, and get it started, it could then just crawl over to a citrus tree. And I think California just has a really good environment for it. [Cheryl]: Okay, we’ll be closing out this poll and bringing up the result screen. I would say, notice that I said in the question that has high levels of FRB—Fuller rose beetle— I would say don’t ship from those orchards is the correct answer, because you’re just gonna…you’re gonna have problems eliminating it. Even with two insecticides and skirt pruning, you’re gonna have trouble. But one strategy you can take is, “okay, I know I have high levels this year, I’ll do the two insecticide treatments and the skirt pruning, but I won’t ship this year, but I’ll get the population down and then next year do the same thing and maybe the population will be low enough that I’ll have made a dent in it and Then the strategy will work [in] year two. Next slide, or…next question. “If you use a soil spray of bifenthrin (Brigade) for control of Fuller rose beetle adults, the following is important—check all that are correct:” Don’t allow the spray to contact fruit, Sprays should be applied before the majority of the adults move into the tree, or the spray should be applied just after peak emergence of adults from the soil So which of these apply? [Cheryl]: Okay, we’re gonna close this one out and see the results. [Beth]: The first two [answers] are correct. You don’t want the spray ever to contact fruit because Brigade has not got any tolerances So you’ve got to keep it on the ground or the trunk of the tree. And the spray should be applied before the majority of the adults have moved into the tree, because you’re really trying to get them as they’re emerging. You don’t want to wait until they’ve already emerged, because you spray the ground, [and] already the bulk has emerged [and] they’re already in the tree. And then the third one—if you wait, that’s the problem. If you wait till after peak emergence of the adults from the soil, you’re spraying the soil, [so] you’re not going to get them. So the first two answers are the correct ones. Next question. So which of these products would…which one of these products is the most effective against Fuller rose beetle adults? 82% of you got the correct answer. Actara is the most effective product against Fuller rose beetle. Esteem would be used for California red scale, Delegate would be used for citrus thrips, Baythroid might be used for katydids or Asian citrus psyllid, but Actara hands-down is the most commonly used and one of the best insecticides For Fuller rose beetle. Next slide. The most effective organic treatment for Fuller rose beetle is… the first one is PyGanic plus oil [in a] foliar treatment, the second is weed stopper to block adult emergence, and the final one is skirt pruning plus a trunk wrap with sticky material. 96% of you are correct. The trunk wrap works. PyGanic is not very effective, weed stopper would be about 50% effective, the skirt pruning and trunk wrap with the stickem would be the most effective, definitely. That would probably get 90% of them. Next question. “How should I monitor to determine if Fuller rose beetle is in the orchard? Check all that are correct.” Multiple choice. Search for notched leaves and fecal pellets, Look under the calyx of the fruit for eggs, [and] shake citrus branches over a cloth for adults. Ok, very good. The majority of you understand that you have multiple ways you can figure out and monitor for FRB in the orchard, and all three of those methods are perfectly reasonable. Ok, that’s it for the questions. [Cheryl]: Alright, and Beth there is one more question that came in for you. [Beth]: Okay. [Cheryl]: Are there other related beetles that are a serious threat to our citrus industry? There are a few other beetles, but they’re not damaging to citrus—the ones that are located here. There are some other nasty ones out in Florida, more subtropical-tropical types, blue-green…I can’t remember any of the names of them, but we kind of keep an eye and a watch out for those because yeah, they could be as damaging, if not more damaging to citrus. Florida has, like, four or five of these different weevils that they deal with out there. [Cheryl]: I think there is a question in chat for you, although it’s going away from me… okay, “Where might you find egg clusters on some of the other host plants you mentioned, for instance, on ornamentals?” [Beth]: Interesting. I’ve never looked on ornamentals, so I don’t know. My guess would be in and around bark, especially if there are cracks in the bark. [It] might be [in] sepals and buds of flowers… don’t really know. Very interesting question. [Cheryl]: There is another question in the chat while we’re working on that— “Where can I find a publication for acceptable levels of citrus pests?” [Beth]: Acceptable levels of citrus pests. I’m not quite sure what that means but if you look at the UC IPM [Pest Management] Guidelines for Citrus, they have biology, monitoring, thresholds, and treatments—both organic and conventional, and discussions of natural enemies. So I think you can find a lot of information there, and there’s also the year-round [IPM] plan for citrus that tells when these various pests [are] up here. [Cheryl]: So there’s a question from Margaret: “My young mandarin tree leaves have been eaten by Fuller rose beetle. Will they recover?” [Beth]: Well eaten… you’d have to define how badly they’re eaten. Usually when there’s a lot of leaf damage in a in a young orchard or a young tree in a backyard, the trees do recover. They just grow more slowly and they may not yield as fast in the first couple years while they’re recovering, because they’re trying to grow more leaf, plant material. But generally they don’t kill a tree. They just slow it down. [Cheryl]: And at this point I don’t have any other—oh wait, there is another question: “Has the Diaprepes beetle been successfully eradicated from California?” No, it has not—it’s still found in Southern California. We were very panicked about it when it first appeared, I can’t even remember what year that was. I want to say it was around 2005. [It] first appeared in the… along the coast in Los Angeles and San Diego counties. It hasn’t really progressed beyond that, so it must just like the coast; it’s a beach bug. And so that’s good news and it hasn’t expanded its territory into commercial citrus. It has a little bit, but not not very far into commercial citrus. Any other questions? [Petr]: So, the question was from Ben, it was “How far can [the] weevil walk at night? If the hills dry up and they start moving, how much distance away from the orchard should be cleared?” [Beth]: That’s an interesting question—how far will they roam? I think they’re pretty simplistic. If there’s food, they really don’t go very far. We don’t, like if I cage them with a plant, I don’t see them roaming around the cage. They’re like, okay, here’s citrus, I’m feeding. So I think the citrus would have to be in pretty bad shape for them to move very far. But I don’t think anyone has ever tracked them. So I can’t answer the question. [Cheryl]: Okay, so I think that was all of the questions we had. Just a reminder, that survey is working, and I think We can put your email address in the chat Beth [Beth]: Sure. [Cheryl]: …if anybody has any additional questions. And also, just to remind anyone that we do have online courses available for CEUs on our website, and the email is there on the website. Okay, so I think that is all, so thank you everybody for attending, and thank you Beth, for presenting. [Beth]: You’re welcome, it was fun.

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