FLORICULTURE 
Root Rot of Trees 
Various forms of root rot attack shade 
as well as fruit and forest trees. 
These will be found fully discussed 
under diseases of the various fruit trees. 
See index. 
Soft Rot of Calla 
Bacillus aroideae, Town 
This organism has caused a serious 
soft rot of the calla which destroys the 
plants about the time of blossoming. 
The disease occurs chiefly in the bulbs, 
flower stalks and petioles. 
Controlled by selection of healthy bulbs 
and by changing beds every three or four 
years. 
Reference 
Duggar, Fungus Diseases of Plants. 
White Rot 
Polyporus squamosus (Huds) Fr. 
This fungus fruits in a conspicuous 
bracket. It is found upon many species 
of forest and ornamental trees. 
Prevent by painting all wounds to pre- 
vent entrance of spores. 
INSECT PESTS OF ORNAMENTAL 
PLANTS 
These plants are attacked by much the 
same list of pests as infest similar spe- 
cies amongst the economic plants. Refer- 
ence to the various fruits and vegetables 
belonging to the same family will usually 
furnish the reader with the desired infor- 
mation as to the method of control in the 
case of a pest of a given plant. 
Holly 
Holly is sometimes troubled with 
scale insects of various species. 
They may be controlled by the usual 
methods adopted for the fruits, which see. 
Ivy or Oleander Seale 
Aspidiotus hederae (Vall.) 
General Appearance 
Circular flat scale, one-sixteenth to one- 
eighth of an inch in diameter, the male 
scales being very much smaller. The col- 
or varies from light to dark gray. On 
lemons this species often appears quite 
red and is occasionally taken for red 
scale (Chrysomphalus aurantii), but the 
lack of the small, central dark exuviz to- 
gether with its smooth, flat surface makes 
it easily distinguishable from red scale 
1003 
and also from the greedy scale (Aspidto- 
tus camellae), which is decidedly 
pointed. 
Life History 
Same as the other species of this genus 
of which the San Jose scale is given as 
typical. This species is cosmopolitan and 
is everywhere throughout the state. It is 
a greenhouse pest and often causes alarm 
to citrus growers by appearing on the 
fruit, but we find it attacks only old “tree 
ripes.” It is perhaps most serious in 
many of the olive orchards in the Sacra- 
mento valley, where it infests the fruits 
so as to make them unfit for pickling pur- 
poses. 
Distribution 
Throughout the entire country. 
Food Plants 
Ivy, oleander, holly, boxwood, orange 
and other citrus species, olive, plum, 
cherry, currant, maple, camellia, grass, 
clover, yucca, asparagus, fern, pepper 
tree. 
Control 
Same as for San Jose scale. 
Natural Enemy 
A small chalcid parasite works effective- 
ly upon this scale. 
EK. O. Essie 
Privet 
San Jose scale. Sometimes troubles 
hedges of this plant. See under Apple 
Pests. 
Red Violet Louse 
Rhopalosiphum violae Perg 
General Appearance 
All forms are dark red; the wings are 
noticeably clouded along the veins which 
easily distinguishes this species from all 
others infesting violets. 
Life History 
Viviparous females, winged and apter- 
ous, bring forth young continually 
throughout the early spring and summer 
months. Evidently the entire life cycle 
is passed upon the violet. 
Food Plants 
Cultivated violets. 
Natural Enemies 
This species is usually held in perfect 
control by internal parasites. 
E O. Essie 
