286 SELECT PLANTS FOR INDUSTRIAL CULTURE 



Rhizopogon magnatum, Corda. 



Europe. One of the edible truffles sold in the markets of Middle 

 Europe, with E. rubescens, Tul. 



Rhododendron, maximum Linne. 



North-East America. Attains a height of 20 feet. Irrespective 

 of its being a fine acquisition for any garden copses, this bush seems 

 of industrial importance, because Mr. C. Eorster asserts that the 

 wood of this and the allied Kalmia latifolia (L.) is equalled only by 

 the best boxwood. This may give a clue to other substitutes for 

 that scarce commodity needed so extensively by the wood- 

 engraver. 



Rhus caustica, Hooker and Arnott. 



Chili, where it is called the Litre. A small or middle-sized tree, 

 the very hard wood of which is used for wheel-teeth, axletrees, and 

 select furniture. The plant seems neither caustic nor otherwise 

 poisonous (Dr. Philippi). 



Rhus copallina, Linne. 



North America, extending to Canada. A comparatively dwarf 

 species. This can be used for tanning. A resin for varnishes is 

 also obtained from this shrub. 



Rhus coriaria, Linne. * 



The Tanner's Sumach. Countries around the Mediterranean Sea. 

 The foliage of this shrub or small tree, reduced to powder, forms 

 the Sumach of commerce. It is remarkably rich in tannic acid, 

 yielding as much as 30 per cent., and is extensively used for the 

 production of a superior Corduan or Maroquin-leather and pale- 

 coloured leathers and dress goods. Sumach allows the leather to 

 carry more grease (Bailment). Price in Melbourne 36 per ton. 

 The cultivation presents no difficulty. It thrives best in loose cal- 

 careous soils, and cannot endure stagnant water. The strongest 

 Sumach is produced on dry ground. A gathering can be obtained 

 from suckers in the first year. The duration of Sumach fields 

 under manure extends to fifteen years. Sumach can also be used 

 for ink and various, particularly black, dyes. Under favourable 

 circumstances as much as a ton of Sumach is obtained from an 

 acre. 



Rhus cotinus, Linne.* 



The Scotino. Countries of the Mediteranean Sea, extending to 

 the Himalayas. The wood of this bush furnishes a yellow pigment. 

 The Scotino, so valuable as a material for yellow and black dye, 

 and as a superior tanning substance, consists of the ground foliage 

 of this plant. It contains up to 24 per cent, tannin. 



