759 



anthracene oils alone were present, while in other varieties the opposite was 

 found to be true. Accordingly, the results in treating wounds were very 

 different. While normal overgrowth occurred with some, with others there 

 was a very visible increase in the size of the wounds due to the dying back 

 of their edges. 



But, aside from this, the carbolineum as a means of closing wounds, 

 even in the viscid varieties abounding in pitch and asphalt, does not stand 

 comparison with plain hard coal tar, for Aderhold has observed that a few 

 weeks after the painting, fungus species had already appeared on the car- 

 bolineum surfaces. Since the painted surface may also crack, under the 

 influence of the atmospharilia, such fungi have a good opportunity of pene- 

 trating into the wood. 



In regard to the very fluid kinds of carbolineum, that is, those rich in 

 light and middle oils, which are warmly recommended for coating trees 

 attacked by red aphis and scale^, the promptness of their action in killing 

 insects is unmistakable, but its protection is not permanent. The recoloni- 

 zation of the painted wounds by red aphis has been repeatedly confirmed. 

 To this should be added, however, the often observed injury to the buds 

 which cannot be avoided in painting or spraying the trees and which is to 

 be ascribed especially to the vaporization and direct action of the light oils. 

 Therefore, the substances should be diluted. It is advisable to use the 

 commercial carbolineum varieties which are soluble in water and to add 

 them to Hme water up to about 20 per cent." ; even an addition of 10 per 

 cent, acts favorably^. 



An action directly favoring growth is said to have been observed in 

 trunks thus coated*, and also the increase of the chlorophyll content of the 

 painted bark has been microscopically determined in Brunswick with the 

 use of a definite brands We believe that this result is due to the fact that 

 in coating smooth barked trunks tears are frequently produced in the bark 

 which must be overgrown subsequently. An increased bark activity in the 

 overgrowth walls has also been proved in common scarification. 



The use of this substance as a coating for trees is advisable only during 

 the dormant period and in fact with some tested brand. "Schacht's fruit 

 tree Carbolineum" (containing 20 to 30 per cent.) has been repeatedly 

 recommended*'. We would never advise spraying in summer. As a means 

 of closing wounds we would prefer coal tar because not only Aderhold's 

 discoveries, but also experiments made by Schweinbez'^ in Hohenheim, and 

 our own have shown no advantage in the use of carbolineum. Its recom- 



1 Baumann, R. Geisenheim. Prakt. Ratg-eber 1905, p. 459. 



2 Praktischer Ratg-eber im Obst- und Gartenbau 1906, No. 49. 



3 Praktische Blatter fiir Pflanzenbau und Pflanzenschutz, herausg-. v. Hiltner. 

 1906, November. 



4 Gartenflora 1906, No. 3. 



5 Graef, tjber Karbolineumversucbe im Jahre 1906, Prakt. Blatter f. Pflanzen- 

 bau und I'flanzenschutz, 1907, Part 3. 



6 Steffen in Prakt. Ratg-eber 1906, p. 23. 



7 Vom Karbolineum. Gartenflora 1906, p. 22. 



