Periodical Literature. 251 



woods are heavy and will not float. This and the lack of rail- 

 road facilities has stood in the way of exploitation. — Hardwood 

 Record. 



BOTANY AND ZOOLOGY. 



The rapid death, or severe injury, of oak 



Insects stands in Western Westfalia since about 



and August, 191 1, is called to attention* by 



Fungi Baumgarten. Suppressed trees, as well as 



on dominant ones, fell a prey, the dead sap- 



Oak. wood being quickly destroyed by beetles. 



The injury is attributed to the oak Tortrix 



(T. viridana) followed by the oak mildew. While neither alone 



is serious, the injury is severe when they work together. 



In 191 1 the insects were active to the end of June. In early 

 July the trees had begun to leaf out again when they were at- 

 tacked by the mildew. The attack was so severe that many 

 thought the oak did not leaf out the second time. The trees 

 then remained bare after August. 



It is stated that the American red oak is immune to the mildew, 

 and almost so to the oak Tortrix. The authors think the fungus 

 not of American origin, but spreading from the Iberian peninsula, 

 crossing over to the oaks from some other host. 



Insekten -und Pilsschdden an den Eichenbestdnden der Provins IVest- 

 falen. Zeitschrift ftir Forst. u. Jagdwesen. March, 1912, 154-161. 



Diseased trees frequently do not produce 

 Detection fruiting bodies to indicate the fungus 



of working in their heartwood. Duesberg 



Heart-Rotten seeks some method for the detection of 

 Trees. such trees so they may be removed in thin- 



ning processes and thus gradually the dis- 

 ease be eradicated. In the case of the European pine affected by 

 Trametes pirn he states after considerable field experience, that 

 infected trees can usually be located by the presence of diseased 

 branch spots which have a brown mycelium beneath the bark at 

 these points and heal differently from normal unifected wounds. 



To test the ability of the ordinary woodsmen to seek out dis- 

 eased trees several were trained in the detection of the spots and, 

 armed with long "pokers", they went through the pole forest in 



