Editing Japanese beetle (section)

== Pest control ==
[[File:Istocheta aldrichi egg on Japanese beetle.jpg|thumb|upright|Egg of the tachinid fly ''[[Istocheta aldrichi]]'' (white) on a Japanese beetle. The fly was introduced from Japan for [[biocontrol]].]]

[[Phenology|Phenological]] models might be useful in predicting the timing of the presence of larvae or adults of the Japanese beetle. Model outputs can be used to support the timely implementation of monitoring and control actions against the pest, thus reducing its potential impact.<ref>{{Cite journal |last1=Gilioli |first1=Gianni |last2=Sperandio |first2=Giorgio |last3=Simonetto |first3=Anna |last4=Colturato |first4=Michele |last5=Battisti |first5=Andrea |last6=Mori |first6=Nicola |last7=Ciampitti |first7=Mariangela |last8=Cavagna |first8=Beniamino |last9=Bianchi |first9=Alessandro |last10=Gervasio |first10=Paola |date=2021-09-20 |title=Modelling diapause termination and phenology of the Japanese beetle, Popillia japonica |journal=Journal of Pest Science |volume=95 |issue=2 |pages=869–880 |language=en |doi=10.1007/s10340-021-01434-8 |s2cid=239147213 |issn=1612-4766 |doi-access=free |hdl=11379/547495 |hdl-access=free}}</ref><ref>{{Cite journal |last1=RÉgniÈre |first1=Jacques |last2=Rabb |first2=Robert L. |last3=Stinner |first3=R. E. |date=1981-06-01 |title=Popillia japonica: Simulation of Temperature-Dependent Development of the Immatures, and Prediction of Adult Emergence |url=https://doi.org/10.1093/ee/10.3.290 |journal=Environmental Entomology |volume=10 |issue=3 |pages=290–296 |doi=10.1093/ee/10.3.290 |issn=1938-2936}}</ref>

Owing to their destructive nature, traps have been invented specifically to target Japanese beetles. These comprise a pair of crossed walls with a bag or plastic container underneath and are baited with floral scent, [[pheromone]], or both. However, studies conducted at the [[University of Kentucky]] and [[Eastern Illinois University]] suggest beetles attracted to traps frequently do not end up in the traps; instead, they land on plants in the vicinity and cause more damage along the flight path and near the trap than may have occurred if the trap were not present.<ref>{{cite web |url=http://www2.ca.uky.edu/entomology/entfacts/ef451.asp |publisher=[[University of Kentucky]] |title=Japanese Beetles in the Urban Landscape |access-date=28 September 2015 |archive-date=16 September 2015 |archive-url=https://web.archive.org/web/20150916170120/http://www2.ca.uky.edu/entomology/entfacts/ef451.asp |url-status=live}}</ref><ref>{{cite journal |journal=[[Journal of Economic Entomology]] |title=Behavioral Explanations Underlying the Lack of Trap Effectiveness for Small-Scale Management of Japanese Beetles. |author1=Paul V. Switzer |author2=Patrick C. Enstrom |author3=Carissa A. Schoenick |s2cid=11509873 |year=2009 |volume=102 |issue=3 |pages=934–940 |doi=10.1603/029.102.0311 |pmid=19610405 |url=https://works.bepress.com/paul_switzer/11/download/ |access-date=2018-04-20 |archive-date=2017-09-22 |archive-url=https://web.archive.org/web/20170922040625/https://works.bepress.com/paul_switzer/11/download/ |url-status=live}}</ref>

During the larval stage, the Japanese beetle lives in [[lawn]]s and other [[grassland]]s, where it eats the roots of [[Poaceae|grasses]]. During that stage, it is susceptible to a fatal disease called milky spore disease, caused by a bacterium called [[milky spore]], ''Paenibacillus'' (formerly ''Bacillus'') ''popilliae.'' The [[United States Department of Agriculture|USDA]] developed this biological control, and it is commercially available in powder form for application to lawn areas. Standard applications (low density across a broad area) take from two to four years to establish maximal protection against larval survival, expanding through the soil through repeated rounds of infection. Control programs based on milky spore disease have been found to work most efficiently when applied as large-scale treatment programs, rather than by isolated landowners. ''[[Bacillus thuringiensis]]'' is also used to control Japanese beetle populations in the same manner.<ref name="Guide"/>

On field crops such as [[Squash (plant)|squash]], floating [[row cover]]s can be used to exclude the beetles, but this may necessitate [[hand pollination]] of the flowers. [[Kaolin spray]]s can also be used as barriers and have been shown to be as effective as standard pesticides programs.<ref>{{Cite journal |last1=Lalancette |first1=Norman |last2=Belding |first2=Robert D |last3=Shearer |first3=Peter W |last4=Frecon |first4=Jerome L |last5=Tietjen |first5=William H |date=2005 |title=Evaluation of hydrophobic and hydrophilic kaolin particle films for peach crop, arthropod and disease management |url=https://onlinelibrary.wiley.com/doi/10.1002/ps.943 |journal=[[Pest Management Science]] |volume=61 |issue=1 |pages=25–39 |doi=10.1002/ps.943 |pmid=15593071 |issn=1526-498X}}</ref>

Research performed by many US extension service branches has shown that [[pheromone trap]]s attract more beetles than they catch; under favorable conditions, only up to three quarters of the insects attracted to a trap will be captured by it.<ref name="Guide"/><ref name="landscapeamerica">{{cite web |url=http://www.landscape-america.com/problems/insects/japanese_beetle_controls.html |title=Japanese beetle control methods |access-date=28 September 2015 |publisher=Ohio City Productions, Inc. |website=Landscape America |archive-date=28 September 2015 |archive-url=https://web.archive.org/web/20150928233858/http://www.landscape-america.com/problems/insects/japanese_beetle_controls.html |url-status=live}}</ref> Traps are most effective when spread out over an entire community and downwind and at the borders (i.e., as far away as possible, particularly upwind) of managed property containing plants being protected.

When present in small numbers, the beetles may be manually controlled using a soap-water spray mixture, shaking a plant in the morning hours and disposing of the fallen beetles,<ref name="landscapeamerica" /> or simply picking them off attractions such as rose flowers, since the presence of beetles attracts more beetles to that plant.<ref name="gardenprof">{{cite web |url=https://sharepoint.cahnrs.wsu.edu/blogs/urbanhort/archive/2010/03/18/disney-and-japanese-beetles.aspx |archive-url=https://web.archive.org/web/20120314082222/https://sharepoint.cahnrs.wsu.edu/blogs/urbanhort/archive/2010/03/18/disney-and-japanese-beetles.aspx |archive-date=14 March 2012 |title=Disney and Japanese Beetles |author=Jeff Gillman |access-date=28 September 2015 |date=18 March 2010 |publisher=Washington State University}}</ref>

Several insect predators and [[Parasitoid|parasitoids]] have been introduced to the United States for [[biocontrol]]. Two of them, the fly ''[[Istocheta aldrichi]]'', a parasite of adult beetles, and the solitary wasp ''[[Tiphia vernalis]]'', a parasite of larvae, are well established with significant but variable rates of parasitism. ''Tiphia vernalis'' reproduces by locating beetle grubs through digging, and on finding one, it paralyzes it with a sting and lays an egg on it; on hatching, the wasp larva consumes the grub. ''Istocheta aldrichi'' instead seeks out adult female beetles and lays eggs on their thoraxes, allowing its larvae to burrow into the insect's body and kill it in this manner. A female ''I. aldrichi'' can lay up to 100 eggs over two weeks, and the rapidity with which its larvae kill their hosts allows the use of these flies to suppress beetle populations before they can themselves reproduce.<ref name="Guide"/><ref>{{Cite journal |last1=Rogers |first1=Michael E. |last2=Potter |first2=Daniel A. |date=2004-06-01 |title=Biology of Tiphia pygidialis (Hymenoptera: Tiphiidae), a Parasitoid of Masked Chafer (Coleoptera: Scarabaeidae) Grubs, with Notes on the Seasonal Occurrence of Tiphia vernalis in Kentucky |journal=Environmental Entomology |volume=33 |issue=3 |pages=520–527 |doi=10.1603/0046-225X-33.3.520 |issn=0046-225X |doi-access=free}}</ref><ref>{{Cite journal |last1=Shanovich |first1=Hailey N |last2=Ribeiro |first2=Arthur Vieira |last3=Koch |first3=Robert L |date=2021-04-01 |title=Seasonal Abundance, Defoliation, and Parasitism of Japanese Beetle (Coleoptera: Scarabaeidae) in Two Apple Cultivars |journal=Journal of Economic Entomology |volume=114 |issue=2 |pages=811–817 |doi=10.1093/jee/toaa315 |pmid=33503253 |issn=0022-0493 |doi-access=free}}</ref>

Soil-dwelling [[nematode]]s are known to seek out and prey on Japanese beetle grubs during the subterranean portion of their life cycle by entering larvae and reproducing within their bodies. Varieties that have seen commercial use as pest control agents include ''[[Steinernema glaseri]]'' and ''[[Heterorhabditis bacteriophora]]''.<ref name="Guide"/>

Recent studies have begun to explore a [[microsporidia]]n [[pathogen]], ''[[Ovavesicula popilliae]]'', as a form of [[Biological pest control|biocontrol]] against Japanese beetles.<ref name=":0">{{Cite journal |last1=Smitley |first1=D |last2=Hotchkiss |first2=E |last3=Buckley |first3=K |last4=Piombiono |first4=M |last5=Lewis |first5=P |last6=Studyvin |first6=J |date=2022-06-07 |title=Gradual Decline of Japanese Beetle (Coleoptera: Scarabaeidae) Populations in Michigan Follows Establishment of ''Ovavesicula popilliae'' (Microsporidia) |url=http://dx.doi.org/10.1093/jee/toac085 |journal=Journal of Economic Entomology |volume=115 |issue=5 |pages=1432–1441 |doi=10.1093/jee/toac085 |pmid=35671221 |issn=0022-0493}}</ref> Initially discovered in 1987, ''O. popilliae'' has been observed inhabiting the [[Malpighian tubule system|malpighian tubules]] of third-instar larvae.<ref>{{Cite journal |last1=ANDREADIS |first1=THEODORE G. |last2=HANULA |first2=JAMES L. |date=February 1987 |title=Ultrastructural Study and Description of ''Ovavesicula popilliae'' N. G., N. Sp. (Microsporida: Pleistophoridae) from the Japanese Beetle, ''Popillia japonica'' (Coleoptera: Scarabaeidae)1 |url=http://dx.doi.org/10.1111/j.1550-7408.1987.tb03123.x |journal=The Journal of Protozoology |volume=34 |issue=1 |pages=15–21 |doi=10.1111/j.1550-7408.1987.tb03123.x |issn=0022-3921}}</ref> This leads to swelling, inefficiency in the gut, and potentially cause [[microsporidiosis]] in the infected beetles. This infection weakens the beetle and creates a suitable breeding ground for [[Opportunistic infection|opportunistic pathogens]].<ref name=":0" />