checked the orchard up the hill yesterday. found Japanese beetles on several trees. went up there originally to spray because our forest tent caterpillars are back this year with a vengeance. sprayed with capt. jacks dead bug juice which has B.T in it. anyone know if that will have any effect on them? if not what else should i spray with to kill them. i assume nothing from the pics of devastated trees posted on here over the years.
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I need to set out indicator traps for them here. Been checking most of my neighbors who do not care if I look as long as I alert them too.
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Bacillus popilliae aka milky spore and Doyeria xylophaga nematodes are what I have in my notes for biological Japanese beetle control
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Here you go 4 oz per gallon and it comes with a measuring device Amazon.com: Sevin Insect Killer Concentrate 32 oz : Patio, Lawn & Garden
" Japanese Beetles: Choices for Conventional and Organic Insecticides
July 06, 2020
Annie Klodd, Bill Hutchison, Eric Burkness, and Dominique Ebbenga. University of Minnesota Extension, University of Minnesota Entomology Department, and UMN IPM Program.
Japanese beetle adults feeding on a grapevine leaf on July 7, 2020. Photo: Annie Klodd
Japanese beetle numbers continue to increase in the weekly trap counts conducted by University of Minnesota researchers in Forest Lake, Hastings, Chanhassen, and Rosemount. As infestations increase on farms, growers should be vigilant about control in order to prevent extensive leaf damage.
Review of Pesticide Options for Japanese Beetles
Japanese beetles release an aggregation pheromone to attract others. Therefore, early control is currently recommended to reduce JB aggregations (or “feeding frenzy” congregations) on apple trees and small fruit crops. Although research is underway this summer to determine economic thresholds for when to control JB in both raspberry and wine grapes, it will be at least another year before we have definitive results on spray timing recommendations to continue to build sustainable IPM and organic management programs.
Regarding insecticides, and beyond efficacy, do not rely on only one chemical for insect control. Rotate products with different modes of action to reduce the risk of resistance development.
Several repellents and anti-feedant products work by slowing the congregation of beetles, and have residual activity of 2-3 weeks. This means that they should be applied every 2-3 weeks based on scouting. These products include:
- Neonicotinoids: Assail, Belay, Wrangler/Alias/Montana. Actara is not as effective, and has a 35 day pre-harvest (PHI) interval.
- Neem oil: Does not effectively kill adults, but is a repellent that reduces immigration into the orchard. Apply neem oil in the evening or night, not in the middle of the day.
With the exception of Assail, the other products listed above do not provide immediate knockdown (death) of Japanese beetles. For immediate knockdown of beetles, one of the following may be applied:
- Imidan (phosmet)
- BeetleGone (Bt)
- Assail
- Carbaryl (i.e. Sevin)
- Pyrethroids (i.e. Mustang Maxx, Danitol, Baythroid, Warrior)
Assail is also effective on 2nd generation coddling moth, so growers may choose to wait to spray this for JB until the 2nd generation coddling moths are active in order to target both at once.
While pyrethroid and carbaryl products are effective for immediate knockdown of JB, they also kill most beneficial insects such as parasitic wasps that help control aphids and other pests. For example, they target predaceous mites that feed on European red mite and spider mites, increasing the occurrence of those pests. These products include Asana, Baythroid, Danitol, Warrior, Proaxis, Mustang Maxx, and Sevin.
A dead Japanese beetle that attempted to feed on a raspberry leaf treated with carbaryl the day prior. Photo: Annie Klodd
Apple growers are currently spraying for leaf hoppers and aphids. These products may have some effectiveness on JB, but more potent products like those listed above will have better results (see also insecticide efficacy results below).
Organic pesticide options:
Entrust provides partial control of Japanese beetles - see the 2019 trial data below. Pyganic (pyrethrum), Surround (kaolin clay) and BeetleGone (Bt) are additional organic options that provide varying levels of control. As stated above, neem oil can be used as a repellent for partial control as well.
Challenges: We understand and respect the desire of growers to use organic insecticides when possible. With that in mind, growers should consider whether the use of certain organic products for Japanese beetles really provides the environmental and safety benefits they are looking for, before applying them. Most organic products effective on JB still kill off-target beneficial insects like pollinators and still require protective equipment to prevent potential injury to the applicator. Additionally, organic products have short residuals (1-2 days) and must be re-applied very frequently for satisfactory control. Frequent application leads to increased fossil fuel use and becomes very expensive over the season. On the plus side, they have very short pre-harvest intervals and allow for harvest shortly after application.
For more details on organic insecticides for JB, see this article from Michigan State, in the section titled “Short PHI and Organic Options.”
Other Management Considerations
According to Dr. Bill Hutchison’s research group at UMN, it is likely that sandy soils are less conducive to JB overwintering by the larval (white grub) stage. For example, the soil at the Hastings trap site is 72% sand, and continues to have the lowest JB counts, compared to all locations sampled to date. Rosemount, with the highest trap counts, is only 15% sand. This is only preliminary data, and geography and the amount of turf habitat may also be contributing to the differences.
It is also important to remember that JB adults can travel long distances, and the soil type on a particular farm will not prevent adult beetles from immigrating onto that farm. The degree to which this happens, depends on farm size, the % sand on a farm, and the relative attraction of fruit and other crops, and wild hosts (such as wild grapes) on a given farm. The landscape analysis of JB dynamics continues.
Female JB have difficulty laying eggs in long grass. Keeping grass over 3 inches may help decrease egg laying within the orchard. Other adults will still fly in from other areas, but this is a simple way to potentially reduce JB numbers without extra cost or inputs. Unfortunately, keeping grass long can promote other issues, like increased SWD habitat and retention of wet conditions that promote disease.
Spot spraying: Some growers have been spot spraying individual trees, or field edges, where JB are observed. While this helps reduce pesticide input and threat to beneficial insects, it also leaves many trees vulnerable to JB infestations as these beetles easily fly between areas of the farm. However, this practice should continue to be practiced to “slow the spread”, depending on each farm situation.
Variety preferences: Researchers at several universities are studying variety preference of JB in several fruits. Anecdotally, it seems to have a strong preference toward Honeycrisp, but much more research is needed. Graduate student Hailey Shanovich (author of a F&V News article on BMSB in April) has been researching variety preferences and will be writing an article on her findings soon.
UMN JB Insecticide Trial 2019 (raspberry):
The Hutchison lab at UMN conducted a replicated insecticide trial to evaluate several products labelled for raspberry and other fruit crops in MN, in July 2019, to compare their efficacy. This location, at UMORE Park (Rosemount Research & Outreach Center), experienced a very good JB infestation for the study.
Before application, there was an average of 27.6 Japanese beetle (JB) adults per meter of raspberry row. After applying the treatments, they compared the number of beetles present after each product, at 1 day and 4 days after application. The plots were 3 rows wide by 10 ft long and sprayed on July 18th with 25 gallons of water per acre on both sides of the row, with a backpack sprayer and a 3 foot boom.
Avg. number of JB adults (% control), 1-day after treatment (DAT), July 19th:
Sevin XLR Plus 64oz/ac = 0.0 JB (100% control) per meter or row
Sevin XLR Plus 32 oz/ac = 0.0 (100%)
Mustang Maxx 4 oz/ac = 0.0 (100%)
Entrust 6 oz/ac = 4.5 (62.5%)
Untreated check = 12.0 JB
Avg. number of JB adults (% control), 4-DAT, July 22nd:
Sevin XLR Plus 64oz/ac = 1.5 JB (87%) per meter of row
Sevin XLR Plus 32 oz/ac = 1.0 (91%)
Mustang Maxx 4 oz/ac = 0.75 (94%)
Entrust 6 oz/ac = 5.75 (51%)
Untreated check = 11.75 JB
This shows that both rates of Sevin and Mustang Maxx provided immediate control, and reasonable residual activity to at least 4 days. Entrust provided partial control.
After Sevin and Mustang Maxx treatments, the beetles continue to visit the plants as new adults emerge from the soil, but typically they won’t feed much or at all. Occasionally a dying adult is found as well.
In this trial, and others, JB populations start to re-build after 7 DAT, from mid-July to mid-August, when adult populations are highest. However, JB infestations vary considerably from farm to farm, and it is critical that on-farm monitoring be done to best track local infestation levels."
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Imidan smokes 'em. So does Carbaryl. Add a spreader/sticker for longer control
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i can get sevin at t.s.c but i cant get a sticker without ordering online. i wonder if i add a little dormant oil in , it will help as a sticker?
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Dawn dishing washing liquid works almost as good as a sticker as anything. Any dishwashing liquid will work.
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The new Sevin isnt Carbaryl. I have no idea if the new stuff kills J. beetles or not.
just picked up some bayer product that says it kills j. beetles. didnt have any other choice the sevin and everything else was cleaned out. everyone’s freaking over the tent caterpillars.
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think i remember my father putting dawn in his sprayers. should i add some vinegar to make the insecticide kill longer? seen some suggest this. got 3 days of sunny dry weather. ill spray this evening once the wind lays down.
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Vinegar is a herbicide to your plants its best not to add any to the water. The reason why people put some in the sprayer sometimes is to make the water more acidic. Alkaline particles in the water binds with certain chemicals reducing the effect of the chemicals if not used right away.
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I agree with Clark…no vinegar
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First you bring them applying manure to your plants and now you want to get rid of them? They are harmless to most plants, corn might be the exception, everything else is basically unharmed by them.
They are not feeding they are making babies(that’s snail damage), the only fruit they feed on is overripe figs.
Completely defoliating trees is harmless? Ok
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…oh yeah, I’ve never seen any damage to corn.
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my apricot and pear are both nearly defoliated. they WILL DIE ! and they aren’t native to the U.S. 1st time seeing them here.
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I’ll go ahead and throw this at you as well.
Don’t buy into the pheromone/bag trap deal. I ran those traps for years, and kept adding more every year. I killed thousands of them every year. Guess what happened? More and more of them showed up annually.
There is no limit to how many of them can procreate. Don’t invite them to your property
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Bt is effective on the tent caterpillars. I have lots of them this year as well, I’ve been pulling them off trees @ the orchard daily. I can no longer get Imidan in NY, but found the last couple years it wasn’t knocking back the Japanese Beetles. I’m using Assail and Avaunt this year for Codling Moth and Plum Curculio with the added bonus of it being effective on the JB’s. It seems way too early for JB’s, no sign of them here yet.
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So far just Leaf rollers here
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Japanese beetles do lots of damage to fruit and foliage here. The more foliage damage that occurs the more it reduces the productivity of the tree the next year. Many people have told me honeycrisp is a problematic apple frequently not bearing regularly. In every case i inquire if japanese beetles have been a problem here in Kansas the answer is yes. My next question is always the same if you have reduced fruit production have you considered that occurs because there is reduced carbohydrate build up from the previous year due to Japanese beetles. The damage is not always obvious. People believe because the tree has not died the beetles are harmless. That is simply not the case the beetles leave a path of destruction everywhere they go. They have no natural enemies unless you count me as their enemy. In Zone 9 not as many carbohydrates are needed for winter. In addition tropical climates favor additional months of growth. Certainly in zone 9 a beetle is likely a minor pest understandably.
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