Editing Natural rubber (section)

=== Other ===
Many other plants produce forms of latex rich in isoprene polymers, though not all produce usable forms of polymer as easily as the Pará.<ref>{{cite web |url=https://digitalcommons.humboldt.edu/cgi/viewcontent.cgi?article=1008&context=botany_jps |title=Plants & Civilization: An Introduction to the Interrelationships of Plants and People. Section 8.4, Latex Plants |last=Smith |first=James P. Jr/ |date=2006 |website=Humboldt State University Botanical Studies Open Educational Resources and Data, Humboldt State University Digital Commons |pages=137–141 |access-date=2019-06-08}}</ref> Some of them require more elaborate processing to produce anything like usable rubber, and most are more difficult to tap. Some produce other desirable materials, for example [[gutta-percha]] (''[[Palaquium gutta]]'')<ref>{{cite web |url=http://www.atlantic-cable.com/Article/GuttaPercha/ |title=The Gutta Percha Company |first=Bill |last=Burns |work=History of the Atlantic Cable & Undersea Communications |access-date=14 February 2009}}</ref> and [[chicle]] from ''[[Manilkara]]'' species. Others that have been commercially exploited, or at least showed promise as rubber sources, include the rubber fig (''[[Ficus elastica]]''), Panama rubber tree (''[[Castilla elastica]]''), various spurges (''[[Euphorbia]]'' spp.), [[lettuce]] (''[[Lactuca]]'' species), the related ''[[Scorzonera tau-saghyz]]'', various ''[[Taraxacum]]'' species, including common dandelion (''[[Taraxacum officinale]]'') and Kazakh dandelion, and, perhaps most importantly for its hypoallergenic properties, [[guayule]] (''Parthenium argentatum''). The term '''gum rubber''' is sometimes applied to the tree-obtained version of natural rubber in order to distinguish it from the synthetic version.<ref name="Ullmann">Heinz-Hermann Greve "Rubber, 2. Natural" in ''Ullmann's Encyclopedia of Industrial Chemistry'', 2000, Wiley-VCH, Weinheim. {{doi|10.1002/14356007.a23_225}}</ref>