PROCEEDINGS OF TWENTY-SIXTH FRUIT-GROWERS' CONVENTION. 15S 



This scale is not a dangerous one, as it has a very interesting and 

 efficient parasite (Aspidiotiphagus citrinus, Craw) coping with it. 

 Strange as it may seem, the yellow scale seldom attacks the wood of 

 the tree, whereas the red scale attacks wood, leaf, and fruit. 



The Soft Orange scale (Lecanium hesperidum) is another species 

 which occasionally gives trouble, but owing to its parasites soon van- 

 ishes again, without having caused much trouble to the grower. This 

 scale attacks a great variety of plants, and is a widespread species, 

 readily recognized by its oblong, flattened shape. The two most common 

 parasites which attack this species are: Coccophagus lecanii, Fitch, a 

 very minute chalcid fly, easily recognized by a yellow band across the 

 thorax, and Microterys flavus, Howd., a beautiful chalcid, which is very 

 abundant and quite large in comparison Avith its co-worker. 



A comparatively new scale insect, for California, is the Purple scale 

 {Mytilaspis citricola. Pack.). This species made its first appearance in 

 some orange trees imported from Florida into Los Angeles County in 

 1888. This is one of the worst pests of the orange, and I am glad to 

 say that very stringent measures are being taken to completely eradicate 

 it. Some very efficient parasites have also been introduced, which will, 

 it is hoped, assist in checking its ravages. This scale does not attack 

 deciduous trees. 



The common Ivy scale (Aspidiotus hederx, Bouche) is another general 

 feeder, and at times becomes quite a pest on lemons. It is, however, 

 kept in check by various ladybirds and numerous other parasites, 

 among which are Aphelinus fuscipennis and A. diaspidis. 



Three scale insects which are very injurious to deciduous trees are 

 the Brown Apricot scale {Lecanium armeniacum, Craw), the Frosted 

 scale (L. pruinosum, Coql.), and the Italian Pear scale (Diaspis pyricolay 

 Delguer). The first two insects attack the apricot, peach, prune, and 

 pear in some sections of the State, but are kept in check by the wonder- 

 ful parasite, Comys fusca, Howd., and wherever introduced, so effective 

 is its work at times that it has been impossible to find sufficient scale 

 on the trees to collect material for introducing the parasite into other 

 sections. It is well for those who find these scale insects established 

 in their orchards to secure a colony of the parasite from Mr. Alexander 

 Craw, of the State Board of Horticulture, as it will save them much 

 labor and expense. 



The Italian pear scale (Diaspis .pyricola) attacks the pear, apple^ 

 prune, and peach tree. When the young limbs are badly attacked, it 

 does not poison them as does the pernicious scale, but it causes deep 

 depressions in the bark and materially stunts the tree. As yet we have 

 no parasite which will reduce the pest, although the twice-stabbed lady- 

 bird {Chilocorus bivulnerus) will keep it down when exposed on the 

 limbs. This scale has the habit of crawling under moss and lichens 



