INJURIES INDUCED BY PLANTS 215 



by cracks formed in the alburnum during drying, it afterwards 

 remains dry, and therefore sound, because the spores are unable 

 to germinate in the dry wood. On all the higher mountains, on 

 the other hand, felling takes place in summer. The wood is at 

 once peeled and piled on supports, and in winter it is conveyed 

 on the snow to the streams, to be sent off in rafts in spring. 

 The timber is dried in the first summer that is to say, directly 

 after being felled and peeled when cracks form through which 

 the spores of fungi enter. During floating the logs become 

 saturated with water, and the cracks close. When the wet logs 

 arrive at the saw-mills they are piled up in thousands, to be 

 sawn up in the course of the summer. The logs that are sawn 

 up in May are, as a rule, perfectly sound, but from June onwards 

 the number of "red-striped" specimens constantly increases, 

 until in autumn it frequently happens that more than 50 per 

 cent, of the logs are so decayed as to furnish but few serviceable 

 boards. This is easily explained, if one considers that the 

 saturated logs are prevented from drying owing to the way 

 they are piled up on one another, and that the high summer 

 temperature is suitable for the germination of the spores present 

 in the cracks, and favours the destructive development of the 

 fungi. 



The owners of saw-mills in the Bavarian Forest calculate that 

 they lose 33 per cent, of their total timber by logs becoming 

 red-striped. For some years I conducted extensive investiga- 

 tions not only at Zwiesel in the Bavarian Forest, but also at 

 Marquardstein and Freising, partly to determine the cause of 

 timber becoming red-striped, and partly with the object of dis- 

 covering a means of preventing the mischief. This is not the 

 place to go into the details of these arduous investigations. 

 I have shortly described the causes of the phenomenon above. 

 As regards the prevention of the disease, it was found to be 

 possible to obtain perfectly sound logs by protecting them 

 against rain by a covering of boards or spruce-bark. Unfor- 

 tunately this only induces another evil namely, the excessive 

 cracking of the timber, which means a very serious shortage in 

 good boards. The rejected red-striped boards are used in 

 houses for underflooring and for false floors. As it very often 

 happens that the wood has not been sufficiently dried to kill the 



