Rubber trees, rubber plants

In the NYT on the 27th, a piece “China’s High Hopes for Growing Those Rubber Tree Plants” by Becky Davis:

[in the face of a huge drop in the price of rubber,] environmental officials just outside Jinghong, [southwest Yunnan Province’s] major city, have been testing a plantation model that they hope will become the blueprint for a more sustainable and economically stable rubber industry.

On approximately 165 acres of land, workers have interspersed the rubber trees with cacao, coffee and macadamia trees, as well as high-value timber species. The mix, promoted as “environmentally friendly rubber,” is intended to decrease soil erosion, improve water quality and increase biodiversity, among other benefits.

So here we have rubber trees. But what about the houseplants commonly called rubber plants? Those, believe it or not, are a species of fig.

Background: the word rubber. An entertaining cluster of meanings here, going back to the verb rub, but developing in several directions. From NOAD2:

a tough elastic polymeric substance made from the latex of a tropical plant or synthetically.

– (rubbers) N. Amer.  rubber boots; galoshes.

– Baseball an oblong piece of rubber or similar material embedded in the pitcher’s mound, on which the pitcher must keep one foot while delivering the ball.

– N. Amer. informal   a condom. [AZ: rubber condoms were popular in the 19th century]

– Brit.  an eraser for pencil or ink marks.

ORIGIN mid 16th cent.: from the verb rub + -er1. The original sense was ‘an implement (such as a hard brush) used for rubbing and cleaning.’ Because an early use of the elastic substance (previously known as caoutchouc) was to rub out pencil marks, rubber gained the sense ‘eraser’ in the late 18th cent. The sense was subsequently (mid 19th cent.) generalized to refer to the substance in any form or use [AZ: three listed above: rubber boots, the baseball rubber, rubber condoms], at first often differentiated as India rubber.

The rubber tree. From Wikipedia:

Hevea brasiliensis, the Pará rubber tree, sharinga tree, or, most commonly, the rubber tree, is a tree belonging to the family Euphorbiaceae. It is the most economically important member of the genus Hevea. It is of major economic importance because the milky latex extracted from the tree is the primary source of natural rubber.

A plantation of rubber trees in India:


Rubber trees are tapped for their sap, in much the same way as maple trees are tapped for their syrup.

Note that Heveas are in the Euphorbia, or spurge, family (which also includes Pointsettias):

The plants [in the family] share the feature of having a poisonous, milky, white latex-like sap, and unusual and unique kind of floral structures. (Wikipedia link)

The rubber plant. From Wikipedia:

Ficus elastica, also called the rubber fig, rubber bush, rubber tree, rubber plant, or Indian rubber bush is a species of plant in the fig genus, native to northeast India, Nepal, Bhutan, Burma, China (Yunnan), Malaysia, and Indonesia.

It is a large tree in the banyan group of figs

Ficus elastica is grown around the world as an ornamental plant, outside in frost-free climates from the tropical to the Mediterranean and inside in colder climates as a houseplant.

Ficus elastica yields a milky white latex, a chemical compound separate from its sap and carried and stored in different cells. This latex was formerly used to make rubber, but it should not be confused with the Pará rubber tree, the main commercial source of latex for rubber making. Just as with Hevea brasiliensis, the latex of Ficus elastica is an irritant to the eyes and skin and is toxic if taken internally.

A potted rubber plant:


On plants in the genus Ficus, including banyans, see my “Fig time” posting. Ficus and Hevea are distant botanically, but they share glossy leaves and the latex.

Leave a Reply

%d bloggers like this: