APPLE DISEASES 



471 



ably parasitic. However, all are agreed 

 that lichens are decidedly objectionable 

 on fruit trees. They harbor insects and 

 fungi, tend to keep the branches moist 

 and more likely to decay, besides being 

 untidy and unsightly. While they may 

 not secure any nourishment from the 

 trees they certainly must interfere seri- 

 ously with the functions of the bark on 

 the younger limbs. 



Two or three pounds of copper sulphate 

 to 50 gallons of water or a o-5-50 Bor- 

 deaux sprayed on the trees before the 

 buds swell in the spring will generally 

 destroy the lichens. A wash such as is 

 used for borers, consisting of one pound 

 of potash or concentrated lye to five gal- 

 lons of water, put on with a brush, is 

 said to be effective. Sone of these mate- 

 rials should be sprayed on the trees when 

 in leaf on account of injuring the foliage. 

 Thorough spraying with 3-3-50 Bordeaux 

 in the spring and early summer, as rec- 

 ommended for apple scab and other fun- 

 gous diseases, would doubtless do much 

 to hold the lichens in check, if not de- 

 stroy them altogether. Hence, if the or- 

 chard is well cared for and sprayed it 

 will not be infested with lichens. 



W. J. Morse. 



Little Leaf. See Rosette. 



Mushroom Root Kot 



Armillaria mellea 

 H. P. B.\Rss 

 In various sections of the Northwest, 

 fruit trees are attacked by the disease 

 known as mushroom root rot or crown 

 rot. Starting from isolated trees in an 

 orchard, it often spreads to surrounding 

 trees, forming infested areas, which en- 

 large from year to year. Examination 

 at the base of affected trees reveals a 

 decayed condition on the underground 

 part of the trunk or on large roots. Un- 

 der favorable conditions clusters of mush- 

 rooms (toadstools) usually appear in the 

 fall at the base of such trees. (See Fig. 

 1.) Old trees and young are equally 

 liable to attack, and once attacked, there 

 is little hope of saving them from ulti- 

 mate destruction. 



Distribution 



While no careful survey has been made 

 to determine its exact distribution, the 

 disease is reported from the northern part 

 of the Willamette valley and from the 

 Hood River valley. It also appears de- 

 structively in Western Washington and 

 California, and similar root rots are re- 

 ported from the Southern and Eastern 

 states. 



0*e-"E.)i.¥- St*-- 



Fig. 1. Mushrooms of Armillaria ilillea In Young Condition. 



