juiyg. I9I7 A Needle Blight of Douglas Fir 103 



In the writer's opinion it plainly belongs in Stictidaceae, a view likewise 

 held by Dr. E. J.Durand, to whom material was submitted. A detailed 

 description of the fungus follows: 



Apothecia embedded in the epidermal layer of the substratum, lenticular or oblong- 

 elliptical, scattered, uniseriate, or more frequently biseriate, on tmdersideof needle, 

 sometimes confluent in two rows on each side of the midrib, rarely situated on the 

 middle nerve, usually arranged at the edge of the needle, causing a discoloration 

 of the tissues on the upper side. Epidermal covering of the apothecia rupturing 

 by an irregular longitudinal slit exposing the brownish convex disk, line of rupture 

 more frequently to one side or rupturing from the center in lobes in single or isolated 

 apothecia. Asci cylindrical to clavate (25) 15. 7 to 19.4 n by 113. 9 to 153.3 m(i5-7 to 

 16.5 IX by 125.9 to 129.2 /u), abruptly rounded above, pedicels short, 8-spored, with fili- 

 form hyalin paraphyses slightly swollen at tips. Ascospores irregularly biseriate or more 

 frequently obliquely uniseriate, hyalin, i-celled, oblong, rounded at the ends, rarely 

 obtusely pointed, more frequently constricted in the middle (80) 6.6 to 7.4 /u by 18.2 to 

 19.8 n (7.0 to 7.4 M by 18.2 to 19.4 ix). The pore of the ascus is colored blue by iodia. 



SUMMARY 



(i) For the past three seasons a needle blight of the Douglas fir has 

 caused great damage to young trees and seedlings in the Northwest. 

 The disease is common both in the nursery and in the forest. 



(2) The systematic position of the causal fungus has not been satis- 

 factorily determined, but it is referred for the present to the Stictidaceae. 

 The fungus is vigorously parasitic and is apparently confined to the 

 Douglas fir. It has been found throughout the entire Northwest. 



(3) Spraying with a solution of soap and Bordeaux mixture (4-4-50) 

 gives indication of being a successful means of controlling the fungus. 



