Andiroba has been used for both interior and exterior construction in the 

 tropics and its properties recommend it for heavy durable construction. 



li. Raj ate Bien ( Vitex C ooperi ), flor Azul ( Vitex Kuyl enii) , These closely- 

 related species are much alike in the characterj.stics of their wood and 

 are combined here for discussion. Their geographical range includes Mexico, 

 Guatemala, Honduras, and British Honduras. Flor Azul is generally small 

 to medium sized but Raj ate Bien occasionally attains large size. 



In weight per cubic foot these timbers compare v;ith Longleaf Pine whereas 

 their mechanical properties more nearly approach those of Douglas Fir. 

 'ii'hen air dry, stiffness is about three-fourths that of Douglas Fir, shrink- 

 age is considerably below that of Longleaf Pine or Douglas Fir, and resis- 

 tance to weathering is excellent, Tlie wood is very durable in resisting 

 attack by decay organisms. 



In Guatemala both species are used for general and durable construction, 

 Rajate Bien being considered the better of the tv/o and the more widely 

 used. The timber should be suitable for flooring, planking, and uses 

 involving exposure to weathering. 



Species Resistant to K ar i ne Borer Attack 



Tests to determine the marine borer resistance of a number of Tropical 

 American woods vere begun by the .J. F. Clapp Laboratories in 19 h8 at Kure 

 Beach, North Caroline. A second series of specimens, together virith a number 

 of domestic woods, was exposed at the same site in June 19^9 and supple- 

 mented by additional tropical woods in August 19U9. In April 19^0, the 

 test panels veve transferred to Harbor Island, North Carolina, where the 

 tests are continuing. The most recent inspection for which results are 

 shown in Table 2 was made in July 19!?1, Since that time specimens of a 

 considerable number of species have been submitted for testing as shown 

 in Table 2 although, of course, no data concerning their resistance are 

 yet available. 



Resistance ratings for 2^ tropical woods and a few domestic woods, summarized 

 from reports of the Clapp Laboratories (1, 2), are shoxirn rn Table 2. At 

 each inspection period following 10-12 months, l6 months, and 21; months of ex- 

 posure, each sioecies was rated on the basis of the degree of resistance to 

 attack by marine borers shovm by sn-ll ( 2 x 3 x 18 inch) specimens of heart- 

 -.Tood. As shOTn in a footnote to Table 2, ratings ranged from "A" indxcatxng 

 no marine borer activity to "E" representing very heavy marine borer activity. 

 aVhen deterioration of a specimen had progressed to a point of severe danage, 

 it was removed from test and cut up for detailed examination. 



lath the exception of Redwood and Bald Cypress, all domestic woods under 

 exposure were completely destroyed within the first 9-month period and 

 these species, together with the tropical wood Balsa, were consequently- 

 removed from test at that time. The least resistant of the other tropical 

 woods had failed after 12 months' exposure, a considerably larger number 

 by 16 months, and all but five of them had been subjected to fairly heavy 

 attack at 2I4. months, 



T - 7 



