558 Fungij Bacteria und Pathologie. 



Sommer 1905 dem Minister den Vorschlag gemacht, zu verfügen : 

 „1. dass in den Gärten (Baumschulen) des Landes, wo der amerika- 

 nische Stachelbeermehltau schon vorhanden ist, alle kranken 

 Sträucher ausgerottet und verbrannt werden, unter Leitung der 

 Distriktsgärtner, und dass zum Decken des dadurch dem 

 Gartenbesitzer verursachten Verlustes diesem vom Staate ein Be- 

 trag, dem halben Wert gesunder Sträucher entsprechend, zuerkannt 

 werde ; 2. dass die Distriktsgärtner, jeder in seinem Bezirk, alle be- 

 findlichen Baumschulen mit Rücksicht auf das Vorhandensein der 

 Krankheit genau untersuchen und, wenn die Krankheit entdeckt 

 werde, sogleich davon der K. Landbau-Akademie Stockholm zu be- 

 richten, wie auch eine vollständige Zerstörung aller kranken Pflanzen 

 vorzunehmen haben und 3. dass ein Königliches Verbot der Einfuhr 

 ausländischer Stachelbeerpflanzen und Staciielbeeren erlassen werde." 

 Daraufhin ist für Schweden 1905 bereits ein Einfuhrverbot erlassen 

 und es werden daselbst weitere energische Schritte zur Bekämpfung 

 und Ausrottung der Seuche getan. Laubert (Berlin-Steglitz). 



Heald, f. D., A Disease oi the Cottonwood, due to Elfvingla 

 megaloma. (Nebraska Agr. Exp. Stat., Report XIX. p. 92—500. 

 4 pl. Feb. 1906.) 



For two years the writer has studied a rot of the heartwood 

 and sapwood oi cottonwood trees in southeastern Nebraska. 

 Careful Observation and study of the disease proved it to be caused 

 by Elfvingla megaloma (Lev.) Murr, which has formerly been called 

 Polyponis applanafiis (P.) Wallr. The first indication of the pre- 

 sence of the fungus in the iiving tree is the appearance oi the 

 sporophores or fruiting bodies. If the attack is severe the tree may 

 show a lessened vigor, as indicated by a poor foliation and casting 

 Oi leaves. The fungus attacks the wood in certain areas more 

 severely than others. The severely infested portions of the wood 

 are arranged in quite marked horizontal strata. Running at right 

 angles to the grain of the wood these transfer strata are very soft 

 and punky, and are füled with a dense tangle of interwoven hyphae, 

 while the intervening wood is much harder, and is decidedly brittle. 

 The appearance of the rotted portions is such that at first it was 

 mistaken for the work of borers. 



Four stages were noted in the process of disintegration of the 

 wood. The first effect of the Invasion by the fungus is the complete 

 disappearance of the starch in the meduüary rays. The second is 

 the digestion or removal of the lignin, since in this stage the wood 

 ceils give only a ceilulose reaction. The third step is the partial 

 destruction of the ceilulose walls. The fourth and last stage is the 

 disintegration of the middle lameilae. Hedgcock. 



Heald, F. D., Report on the Plant Diseases prevalent in 

 Nebraska during the Season of 190 5. (Nebraska Agr. 

 Exp. Stat., Report XIX. p. 20—60. February 1906.) 



This report includes a brief summary of the most important 

 diseases of trees, shrubs and vegetables in the state of Nebraska 

 lor the year 1905. The writer divides the subjects into diseases of: 



1. Tree fruits. Malus malus is reported to have fifteen diseases; 

 Prunus armenicola, one disease, Prunus sp. (Cherry) eight, Prunus 

 persica, six, Pyrus communis, two, Prunus sps. (Plum), seven. 



