the wood sorrel family, is composed genera and species that are characterized by their compound leaves with leaflets having thickened bases (pulvini). Many species show movement by closing their leaves or leaflets at night or in bad weather. Oxalic acid accumulates in the plants, giving them their distinctive sour or “sorrel” taste. Most members of Oxalidaceae are found in tropical regions, but some are native or even weedy in temperate regions.

Berry, Paul E.. "Oxalidales". Encyclopedia Britannica, 27 Oct. 2023, https://www.britannica.com/plant/Oxalidales. Accessed 17 October 2026.