View source for Solanum elaeagnifolium

{{Taxobox
| color = lightgreen
| name = Silverleaf nightshade
| image = Solanum elaeagnifolium.jpg
| image_width = 240px
| regnum = [[Plant]]ae
| divisio = [[Magnoliophyta]]
| classis = [[Magnoliopsida]]
| subclassis = [[Asteridae]]
| ordo = [[Solanales]]
| familia = [[Solanaceae]]
| genus = ''[[Solanum]]''
| species = '''''S. elaeagnifolium'''''
| binomial = ''Solanum elaeagnifolium''
| binomial_authority = [[Antonio José Cavanilles|Cav.]]
}}

'''Silverleaf nightshade''', ''Solanum elaeagnifolium'', is a common [[weed]] of western [[North America]], also found in [[South America]].

It is a [[perennial plant|perennial]] 10 [[metre|cm]]<ref name=Niehaus>{{cite book | author=Theodore F. Niehaus, Charles L. Ripper, and Virginia Savage | title=A Field Guide to Southwestern and Texas Wildflowers | publisher=Houghton Mifflin Company | year=1984 | id=ISBN 0-395-36640-2}}</ref> to 1 m in height.  The stems are covered with short spines, ranging from very few on some plants to very dense on others.  Leaves and stems are also covered with downy hairs that lie against and hide the surface, giving a silvery or grayish appearance.<ref name = Cronquist>{{cite book | author=Arthur Cronquist, Arthur H. Holmgren, Noel H. Holmgren, James L. Reveal, Patricia K. Holmgren | title=Intermountain Flora; Vascular Plants of the Intermountain West, U.S.A., vol. 4. Subclass Asteridae (except Asteraceae) | publisher=The New York Botanical Garden | year=1984 | id=ISBN 0-231-04120-9}}</ref>

The leaves are up to 15 cm long and usually only 0.5 to 2.5 cm wide, with shallowly waved edges (one of the distinctions from the closely related [[Carolina horsenettle]], which has wider, more deeply indented leaves).  The flowers, appearing from April to August, have five petals united to form a star, ranging from blue to pale lavender or occasionally white; five yellow [[stamen]]s and a [[pistil]] form a projecting center.  The plant produces glossy yellow, orange, or red [[berry|berries]] that last all winter and may turn brown as they dry.<ref name=Cronquist/>

Its range is from [[Kansas]] south to [[Louisiana]], and west through the Mexican-border states of the [[United States]] into [[Mexico]], as well as [[Uruguay]], [[Argentina]], and [[Chile]].<ref name=grin>[http://www.ars-grin.gov/cgi-bin/npgs/html/taxon.pl?101507 GRIN/NPGS Taxonomy Information], accessed [[16 June]], 2006</ref>  Possibly it originated in North America and was accidentally introduced to South America<ref name=Wash>[http://www.nwcb.wa.gov/weed_info/Solanum_elaeagnifolium.html Silver Nightshade] from the Washington State Noxious Weed Control Board, accessed [[16 June]], 2006</ref> or vice-versa.<ref name=grin/>  It can grow in poor soil with very little water. It spreads by [[rhizome]]s as well as seeds, and is common in disturbed habitats.  Partly because of these characteristics, it is considered a [[noxious weed]] in 21 U.S. states and in countries such as [[Australia]], [[Egypt]], [[Greece]], [[India]], [[Israel]], [[Italy]], [[South Africa]], and [[Zimbabwe]].<ref name=Wash/><ref name=Ore>[http://www.oregon.gov/OISC/docs/pdf/oisc_plan6_05.pdf Oregon Invasive Species Action Plan], accessed [[16 June]], 2006</ref>  It is toxic to livestock and very hard to control, as rootstocks less than 1 cm long can regenerate into plants.<ref name=Cal>[http://www.cdfa.ca.gov/phpps/ipc/weedinfo/solanum-americanum.htm Solanum genus part 2] from the California Department of Food and Agriculture's Encycloweedia, accessed [[16 June]], 2006</ref>  (However, some eccentric gardeners encourage it as a [[xeriscape]] [[ornamental plant|ornamental]].)

[[Image:Solanum elaeagnifolium2.jpg|thumb|left|Habit, unripe berries (green with stripes, center), and previous year's stems and berries (orange, upper left)]]
The [[Pima]] Indians used the berries as a vegetable [[rennet]], and the [[Kiowa]] used the seeds together with [[brain]] tissue to tan [[leather]].<ref name=Wash/>

Other common names include bull-nettle, prairie-berry, silverleaf-nettle, (white) horse-nettle, silver nightshade, silver-leaf bitter-apple (South Africa), satansbos (in [[Afrikaans]]), and trompillo (in [[Spanish language|Spanish]]).<ref name=Cronquist/><ref name=grin/>