a testing ground in the agricultural biotechnology field. Bayer (formerly Monsanto) owns and operates a facility located just south of the city, which in 1987, was the site of the world's very first biotechnology field trial – first with tomatoes and later that year with soybeans. The facility was also home to the first triple stacked corn trial in 1998, which later became a part of one of Monsanto's top-selling products. The facility was further expanded in 2008, and now consists of sixteen greenhouses and almost of land for field testing. The Downtown Historic District is presently home to some antique stores and gift shops, some clothing and shoe stores, a pharmacy, public library, post office, and several local restaurants and banks. Most of the growth that has occurred since the early 1990s has been in the southern and southwestern portions of the city, where new residential subdivisions and retail shopping centers have been built, and where numerous land annexations have been made by the city. Geography Jerseyville is located at (39.120789, -90.327545). According to the 2010 census, Jerseyville has a total area of , all land. Climate Typically, the city's climate reflects most Midwest cities, located in the transitional zone between the humid continental climate type and the humid subtropical climate type (Köppen Dfa and Cfa, respectively), with neither large mountains nor large bodies of water to moderate its temperature. Spring is the wettest season and produces severe weather ranging from tornadoes to snow or ice storms. Summers are hot and humid, and the humidity often makes the heat index rise to temperatures feeling well above . Fall is mild with lower humidity and can produce intermittent bouts of heavy rainfall with the first snow flurries usually forming in late November. Winters can be cold at times with periodic light snow and temperatures below freezing. In recent years, average temperatures in Jerseyville have ranged from a low of in January to a high of in July. The record low temperature of was recorded in January 1977 and the record high temperature of was recorded in July 1954. Average monthly precipitation ranges from in February to in May. Demographics As of the census of 2000, there were 7,984 people, 3,260 households, and 2,089 families residing in the city. The population density was . There were 3,423 housing units at an average density of . The racial makeup of the city