APPLE DISEASES 
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 5-5-50. 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. None 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. 
LittLte LEAF. See Rosette. 
471 
Mushroom Root Rot 
Armillaria mellea 
H. P. Barss 
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. 
Fig. 1. Mushrooms of 
Armillaria Mellea in Young Condition. 
