685 



CHAPTEE V. 



NEEDLE-CAST.* 



1. Description. 



SINCE the end of the eighteenth century, a disease, termed 

 needle-cast (in German, Schiitte), has been remarked on young 

 pines, the external signs of which consist in the gradual 

 reddish or reddish-brown discoloration of their 1- or 2- year-old 

 needles, which eventually die and fall off the plants. As a 

 rule these symptoms appear first in the spring (Vor-winter 

 Schiitte), but not unfrequently also in the autumn and early 

 winter (Nach-icinter Schiitte), and in South Germany the 

 latter often happens in years when the ground is free from 

 snow. A steel-blue or violet colour of the 1 -year-old pine- 

 needles in autumn is no sign of disease, provided yellow or 

 reddish-coloured spots do not also occur ; this is an instance 

 of the normal winter-colour of many evergreen plants, which 

 disappears as the thermometer rises in the spring, and gives 

 place to the ordinary green colouring of the needles. The 

 reddish discoloration and death of the needles proceeds from 

 their tips downwards, and chiefly affects the lower parts of 

 the plant near the ground. Pines thus affected resemble 

 those injured by drought, but at the commencement of the 

 disease more or less regularly distributed dark spots and 

 stripes appear, and later, in May, small black sporangia of 

 the fungus Lophodermium Pinastri, Schrad.t Also resin 

 collects on the sickly needles. The worst form of the disease 

 may be recognised when the buds become encrusted with 

 resin and dry-up, and then no recovery is possible for the 

 diseased plants. 



* Freiherr von Lbffelholz, " Beitrag zu einer kritischen Nachweisung iiber 

 die Schiitte-krankheit der Kief er." Berlin, 1865. Holzner, Dr. Georg, "Die 

 -Beobachtungen uber die Schiitte der Kiefer und die Winterfarbung immergruner 

 Gewachse." Freising, 1877. 



t See p. 465. 



