APPLE DISEASES 
remove the cause, and root injury is a 
cause without which I do not believe 
rosette will exist, yet root injuries are 
not all from the same causes, and the 
varied contributory causes are conditions 
which precede the results and we must 
strive to correct them. 
For instance, if there is a condition 
where the root hairs are perishing for 
lack of water, the remedy is more water. 
If the root hairs are being injured by 
too much water, the remedy is less water. 
If there is underground seepage, the 
remedy is drainage. 
If the roots are cramped by a hard 
soil, the remedy is dynamite or alfalfa. 
If field mice or gophers injure them, 
kill the mice and gophers. 
If the soil lacks humus, manure it. 
If it has too much alkali, wash it out, 
or drain the land, if you can. 
If root injuries are caused by aphis, 
kill the aphis. 
In every case of a rosetted orchard [ 
have observed, where alfalfa or clover 
has been sown, the conditions have been 
improved. This would not correct the in- 
jury where the alkali or other salts were 
strong enough to kill the alfalfa. 
In case the cause is crown gall, or some 
other form of gall, I have no knowledge 
of a remedy which I could recommend, 
but think that alfalfa or dynamite might 
open up the soil and improve the con- 
ditions. I have strong faith that alfalfa 
will improve the orchard conditions in the 
arid regions. 
Opinions from Various Sources 
In 1897 Cavara caused on the roots of 
the vine, what he called “tuberculosis or 
gall,” by means of material which he had 
shipped from Venice and from which he 
made pure cultures and performed suc- 
cessful inoculations. The following cita- 
tions are from his article on the subject: 
“The plant attacked presents the fol- 
lowing characteristics: 
“A rachitic development of the leaves. 
Color of the leaf greenish yellow.” The 
work “ratchitic’ means a bunching or 
clustering of the leaves as in case of a 
racime or spike. 
In this case then, we have a bunching 
483 
of the leaves, a yellowing of the leaves; 
this bunching and yellowing caused by 
gall, 
In U S Bulletin No. 218, Bureau Plant 
Industry, it is stated that an analysis of 
sap from crown gall showed that it con- 
tained an amount of acetic acid. See p. 
174, Bull. 2138 
Professor J. W. Toumey, formerly of 
the Arizona Station, said’ “The warty 
growth in crown gall is due to a vege- 
table organism or slime mould fungus. 
When these galls grow until they girdle 
the trunk, they interfere with the move- 
ment of the sap. Affected trees show 
signs of starvation, yellowish foliage and 
enfeebled growth Young trees often die 
of the disease.” 
Here Professor Toumey describes some- 
thing very similar to rosette, and affirms 
that these conditions are due to crown 
gall. 
The U. S. Bulletins with those of Cana- 
da give the information that 485 species 
of trees, shrubs and plants have been ob- 
served to have galls, caused by insects, 
rodents, birds, or other injuries, and give 
a number of cuts showing the effects up- 
on the leaves or branches, and the tend- 
ency is always toward a rosetted condi- 
tion. 
The article on “Galls’” in the new Ency- 
clopedia Britannica shows that gall is 
found in Europe on many of the forest 
trees. I have found the same things in 
the forests of this country, and on some 
of the forest trees in the orchards of this 
country, and have often been able to dis- 
cover gall on the roots because of the 
rosetted condition of the top first at- 
tracting my attention. 
In North Carolina Bulletin No. 206 Pro- 
fessor Smith says: “The presence of 
woolly aphis on the roots may often be 
detected from the outward appearance of 
the trees. If badly infested, they usually 
present a sickly appearance, indicated by 
scant foliage of a yellowish color, and a 
dwarfed growth. After the aphids have 
been present for two or three years, the 
roots become so badly weakened that the 
entire tree may become loosened or 
pushed over. Similar to all plant lice, the 
