Editing Grasshopper (section)

===As pests===
[[File:Grasshopper eating the maize leaf.jpg|thumb|left|Crop pest: grasshopper eating a [[maize]] leaf]]

Grasshoppers eat large quantities of foliage both as adults and during their development, and can be serious pests of arid land and prairies. Pasture, grain, forage, vegetable and other crops can be affected. Grasshoppers often bask in the sun, and thrive in warm sunny conditions, so drought stimulates an increase in grasshopper populations. A single season of drought is not normally sufficient to stimulate a major population increase, but several successive dry seasons can do so, especially if the intervening winters are mild so that large numbers of nymphs survive. Although sunny weather stimulates growth, there needs to be an adequate food supply for the increasing grasshopper population. This means that although precipitation is needed to stimulate plant growth, prolonged periods of cloudy weather will slow nymphal development.<ref name=Capinera1710>Capinera, 2008. pp. 1710–1712</ref>

Grasshoppers can best be prevented from becoming pests by manipulating their environment. Shade provided by trees will discourage them and they may be prevented from moving onto developing crops by removing coarse vegetation from fallow land and field margins and discouraging thick growth beside ditches and on roadside verges. With increasing numbers of grasshoppers, predator numbers may increase, but this seldom happens rapidly enough to have much effect on populations. Biological control is being investigated, and spores of the protozoan parasite ''[[Nosema locustae]]'' can be used mixed with bait to control grasshoppers, being more effective with immature insects.<ref>{{cite web |url=https://www3.epa.gov/pesticides/chem_search/reg_actions/registration/fs_PC-117001_01-Oct-00.pdf |title=''Nosema Locustae'' (117001) Fact Sheet |publisher=U.S. Environmental Protection Agency |date=October 2000 |access-date=6 August 2016 |url-status=live |archive-url=https://web.archive.org/web/20160817073223/https://www3.epa.gov/pesticides/chem_search/reg_actions/registration/fs_PC-117001_01-Oct-00.pdf |archive-date=17 August 2016 }}</ref> On a small scale, [[Azadirachta indica|neem products]] can be effective as a feeding deterrent and as a disruptor of nymphal development. [[Insecticide]]s can be used, but adult grasshoppers are difficult to kill, and as they move into fields from surrounding rank growth, crops may soon become reinfested.<ref name=Capinera1710/>

Some grasshopper species, like the Chinese rice grasshopper, are a pest in [[rice]] paddies. Ploughing exposes the eggs on the surface of the field, to be destroyed by sunshine or eaten by natural enemies. Some eggs may be buried too deeply in the soil for hatching to take place.<ref>{{cite web |title=Rice grasshopper (Oxya chinensis) |url=http://www.plantwise.org/KnowledgeBank/Datasheet.aspx?dsid=38206 |publisher=Plantwise |access-date=16 December 2015 |url-status=live |archive-url=https://web.archive.org/web/20170525024556/http://www.plantwise.org/KnowledgeBank/Datasheet.aspx?dsid=38206 |archive-date=25 May 2017 }}</ref>
[[File:"Grangers versus Grasshoppers on the Irrepressible Conflict," St. Peter, Minnesota - DPLA - 22822be747ad4bcf8dd4974ee2274aa6 (cropped).jpg|alt=Illustration of grasshoppers attacking farmers.|thumb|Grangers versus Grasshoppers on the Irrepressible Conflict, St. Peter, Minnesota.]]
Locust plagues can have devastating effects on human populations, causing [[famine]]s and population upheavals. They are mentioned in both the [[Quran|Qur’an]] and the [[Bible]] and have also been held responsible for [[cholera]] epidemics, resulting from the corpses of locusts drowned in the Mediterranean Sea and decomposing on beaches.<ref name=Capinera1181>Capinera, 2008. pp 1181–1183</ref> The [[Food and Agriculture Organization|FAO]] and other organisations monitor locust activity around the world. Timely application of pesticides can prevent nomadic bands of hoppers from forming before dense swarms of adults can build up.<ref name=FAO>{{cite web |url=http://www.fao.org/ag/locusts-CCA/en/1013/ |title=Control |work=Locusts in Caucasus and Central Asia |publisher=Food and Agriculture Organization of the United Nations |access-date=2 April 2015 |url-status=live |archive-url=https://web.archive.org/web/20150404223501/http://www.fao.org/ag/locusts-CCA/en/1013/ |archive-date=4 April 2015 }}</ref> Besides conventional control using contact insecticides,<ref name=FAO/> [[biological pest control]] using the [[entomopathogenic fungus]] ''[[Metarhizium acridum]]'', which specifically infects grasshoppers, has been used with some success.<ref>{{cite journal| title=Biological Control of Locusts and Grasshoppers | journal=Annual Review of Entomology| volume=46| pages=667–702 | year=2001 |author1=Lomer, C.J. |author2=Bateman, R.P. |author3=Johnson, D.L. |author4=Langewald, J. |author5=Thomas, M. | doi=10.1146/annurev.ento.46.1.667 | pmid=11112183 }}</ref>