Editing Boll weevil (section)

==Control==
{{See also|Boll Weevil Eradication Program}}

During early years of the weevil's presence, growers sought relatively warm soils and early-ripening cultivars. Following World War II, the development of new pesticides such as [[DDT]] enabled U.S. farmers again to grow cotton as an economic crop. DDT was initially extremely effective, but U.S. weevil populations developed resistance by the mid-1950s.<ref name=scho>{{cite book|author=Timothy D. Schowalter|title=Insect Ecology: An Ecosystem Approach|url=https://books.google.com/books?id=2KzokTLIysQC&pg=PA482|access-date=8 November 2011|date=31 May 2011|publisher=Academic Press|isbn=978-0-12-381351-0|page=482}}</ref> [[Methyl parathion]], [[malathion]], and [[pyrethroid]]s were subsequently used, but environmental and resistance concerns arose as they had with DDT, and control strategies changed.<ref name=scho/>

While many control methods have been investigated since the boll weevil entered the United States, insecticides have always remained the main control methods. In the 1980s, entomologists at Texas A&M University pointed to the spread of another invasive pest, the [[red imported fire ant]], as a factor in the weevils' population decline in some areas.<ref>{{Cite journal |last1=Fillman |first1=D. A. |last2=Sterling |first2=W. L. |name-list-style=amp |date=December 1983 |title=Killing power of the red imported fire ant [Hym.: Formicidae]: a key predator of the boll weevil [Col.: Curculionidae] |url=http://link.springer.com/10.1007/BF02372186 |journal=Entomophaga |language=en |publisher=BioControl: Volume 28, Number 4 / December, 1983 |volume=28 |issue=4 |pages=339–344 |doi=10.1007/BF02372186 |bibcode=1983BioCo..28..339F |issn=0013-8959 |s2cid=38550501}}</ref>

Other avenues of control that have been explored include weevil-resistant strains of cotton,<ref>{{Cite journal |last1=Hedin |first1=Paul A. |last2=McCarty |first2=Jack C. |date=October 1995 |title=Boll weevil Anthonomus grandis Boh. oviposition is decreased in cotton Gossypium hirsutum L. lines lower in anther monosaccharides and gossypol. |url=https://pubs.acs.org/doi/abs/10.1021/jf00058a035 |journal=Journal of Agricultural and Food Chemistry |language=en |volume=43 |issue=10 |pages=2735–2739 |doi=10.1021/jf00058a035 |issn=0021-8561}}</ref> the parasitoid wasp ''[[Catolaccus grandis]]'',<ref>{{cite web | url = http://www.biocontrol.entomology.cornell.edu/parasitoids/catolaccus.html | author = Juan A. Morales-Ramos | publisher = Biological Control: a guide to Natural Enemies in North America | title = ''Catolaccus grandis'' (Burks) (Hymenoptera: Pteromalidae) | url-status = dead | archive-url = https://web.archive.org/web/20131014100230/http://www.biocontrol.entomology.cornell.edu/parasitoids/catolaccus.html | archive-date = 2013-10-14 }}</ref> the fungus ''[[Beauveria bassiana]]'',<ref>{{cite web|url=http://www.encyclopedia.com/doc/1G1-14987730.html|title=boll weevil facts, information, pictures - Encyclopedia.com articles about boll weevil|website=www.encyclopedia.com}}</ref> and the ''Chilo'' iridescent virus{{cn|date=June 2024}}. [[Genetic engineering|Genetically engineered]] [[Bacillus thuringiensis|Bt]] cotton is not protected from the boll weevil.<ref>[http://life.bio.sunysb.edu/ee/geeta/Bt-Cotton.html Bt susceptibility of insect species] {{webarchive |url=https://web.archive.org/web/20080409214952/http://life.bio.sunysb.edu/ee/geeta/Bt-Cotton.html |date=April 9, 2008 }}</ref>

<gallery class="center" widths="250px" heights="275px">
image:"Beat the boll weevil...With a little more care at every step you- not the weevils- get the crop. Get a good cotton... - NARA - 512572.jpg|"Beat the boll weevil..." (U.S. Food Administration, Educational div., Advertising section, 1918–1919)
image:Boll weevil eradication.jpg|Eradication map (USDA, 2006)
</gallery>

Although it was possible to control the boll weevil, the necessary insecticide was costly. The goal of many cotton entomologists was to eventually eradicate the pest from U.S. cotton. In 1978, a large-scale test was begun in eastern North Carolina and in adjacent Southampton County, Virginia, to determine the feasibility of eradication. Based on the success of this test, area-wide programs were begun in the 1980s to eradicate the insect from whole regions. These are based on cooperative effort by all growers together with the assistance of the [[Animal and Plant Health Inspection Service]] (APHIS) of the United States Department of Agriculture (USDA).{{citation needed|date=January 2014}}

Research methods were developed. The ability to distinguish between individuals which had eaten certain substances and those which had not was needed, to determine effectiveness of the [[active ingredient]]s used. Lindig et al. 1980 studied several dietary [[dye]]s as markers. They find [[Calco Oil Red N-1700]] to persist from larval feeding to adulthood, and for females to their eggs, although the resulting first [[instar]] was too faintly pink to be distinguishable.<ref name="Hagler-Jackson-2001">{{cite journal | last1=Hagler | first1=James R. | last2=Jackson | first2=Charles G. | title=Methods for Marking Insects: Current Techniques and Future Prospects | journal=[[Annual Review of Entomology]] | publisher=[[Annual Reviews (publisher)|Annual Reviews]] | volume=46 | issue=1 | year=2001 | issn=0066-4170 | doi=10.1146/annurev.ento.46.1.511 | pages=511–543| pmid=11112178 }}</ref><ref name="Silver-2008">{{cite book | editor-last=Silver | editor-first=John | title=Mosquito Ecology - Field Sampling Methods | publisher=[[Springer Publishing|Springer]] | publication-place=[[Dordrecht, Netherlands]] | year=2008 | isbn=978-1-4020-6666-5 | oclc=233972575 | pages=xxi+1477}}</ref>{{rp|1274}}

The program has been successful in eradicating boll weevils from all cotton-growing states with the exception of Texas, and most of this state is free of boll weevils.{{citation needed|date=March 2022}} Problems along the southern border with Mexico have delayed eradication in the extreme southern portions of this state. Follow-up programs are in place in all cotton-growing states to prevent the reintroduction of the pest. These monitoring programs rely on pheromone-baited traps for detection.{{citation needed|date=January 2014}} The boll weevil eradication program, although slow and costly, has paid off for cotton growers in reduced pesticide costs. This program and the [[Cochliomyia|screwworm program]] of the 1950s are among the biggest and most successful insect control programs in history.<ref>{{Cite web|url=http://deltafarmpress.com/most-successful-biological-pest-exclusion-program-ever|title=Delta Farm Press|date=2006-01-06|website=Delta Farm Press|access-date=2 September 2016}}</ref>

[[File:Boll Weevil monument angle at Enterprise City Hall.JPG|thumb|left|175px|The boll weevil plaque in [[Enterprise, Alabama]]]]