Editing Lupinus (section)

== Description ==
The species are mostly [[herbaceous]] [[perennial plant]]s {{convert|0.3|-|1.5|m|ft|0|abbr=off}} tall, but some are [[annual plant]]s and a few are [[bush lupin|shrubs]] up to {{convert|3|m|ft|0|abbr=on}} tall. An exception is the ''chamis de monte'' (''[[Lupinus jaimehintonianus]]'') of [[Oaxaca]] in [[Mexico]], which is a [[tree]] up to {{convert|8|m|ft|0|abbr=on}} tall.<ref name=villa>{{cite journal |last1= Villa-Ruano |first1= N. |display-authors= et al. |year= 2012 |title= Alkaloid profile, antibacterial and allelopathic activities of ''Lupinus jaimehintoniana'' BL Turner (Fabaceae). |url= http://www.doiserbia.nb.rs/(A(-wsTwqzGzgEkAAAAMDM3NmY1ODMtNDRkMS00YTNmLWExZTgtOGMwZDk0MjJlNWQ5qQymZSev6uZabo19x2jsEpadeOw1))/img/doi/0354-4664/2012/0354-46641203065V.pdf |journal= Archives of Biological Sciences |volume= 64 |issue= 3|pages= 1065–71 |doi= 10.2298/ABS1203065R|access-date=}}</ref>

Lupins have soft green to grey-green leaves which may be coated in silvery hairs, often densely so. The leaf blades are usually [[palmate]]ly divided into five to 28 leaflets, or reduced to a single leaflet in a few species of the [[southeastern United States]] and eastern [[South America]].<ref>{{cite journal |last1= Planchuelo |first1= Ana Maria |last2= Dunn |first2= David B. |year= 1984 |title= The Simple Leaved Lupines and Their Relatives in Argentina |url= https://www.biodiversitylibrary.org/page/16166394 |journal= Annals of the Missouri Botanical Garden |volume= 71 |issue= 1 |pages= 92–103 |doi= 10.2307/2399057|jstor= 2399057 |bibcode= 1984AnMBG..71...92P |access-date=}}</ref>

The flowers are produced in dense or open whorls on an erect spike, each flower {{Convert|1–2|cm|abbr=off|frac=8}} long. The pea-like flowers have an upper standard, or banner, two lateral wings, and two lower [[petal]]s fused into a keel. The flower shape has inspired common names such as [[bluebonnet (plant)|bluebonnets]] and [[Lupinus perennis|quaker bonnets]].

The fruit is a [[legume|pod]] containing several seeds. The seeds contain [[alkaloid]]s which lend them a bitter taste.

[[Extrafloral nectaries]] have been found on a species in Arizona.<ref>{{cite journal |date=2012-10-18 |first1=Marjorie G. |last1=Weber |first2=Kathleen H. |last2=Keeler |title=The phylogenetic distribution of extrafloral nectaries in plants |pages=1251–1261 |doi=10.1093/aob/mcs225 |journal=Annals of Botany |eissn=1095-8290 |volume=111 |issue=6|pmid=23087129 |pmc=3662505 }}</ref>