VARIOUS BORERS IN FRUIT TREES 477 



Cottony Cushion Scale or Fluted Scale (Icerya purchasi). This 

 promised at one time to be the most grievous of all scales in its rapid 

 increase and wide range of food plants, but it was speedily reduced by 

 an Australian ladybird, Novius (Vedalia) cardinalis, introduced by 

 Albert Koebele, with such success that specimens were for a number 

 of years rarely seen, but have recently become abundant in some 

 localities. 



Mealy Bugs. Closely allied to the scales are the mealy bugs 

 (species of dactylopius), soft and of a pale pink color, generally cov- 

 ered with a whitish mealy powder, hence the name. The common 

 species is found in nearly every greenhouse in the world, and in Cali- 

 fornia climate lives in the open air on many kinds of plants, and has at 

 various times proved quite troublesome. Unless checked by natural 

 enemies, the mealy bugs multiply very rapidly, and mass themselves 

 in the corners of the leaves. The plants turn black from the fungus 

 growth growing on the honeydew, and the bush presents the same 

 appearance as a scale-infested plant. With the aid of a magnifier the 

 appearance of the mealy bugs, as different from scales can be readily 

 recognized. 



Remedies for Scale Insects. Though most of the scale insects 

 are attacked by parasitic and predaceous insects, as already stated, 

 these natural agencies have generally not proved rapid enough to cope 

 with the increase of the scales, and insecticides have to be employed 

 to save the fruit and trees. There is a vast number of these washes, 

 many of which will do good work if thoroughly applied, which is 

 usually the secret of success. A few which have proved of special 

 value will be given at the close of this chapter. 



INSECTS BORING IN TWIG, STEM, OR ROOT 



Peach Twig-Borer or Peach Worm. This larva is probably 

 the most serious insect pest that the California peach grower has had to 

 contend with. The creature hibernates as a young larva in burrows 

 in the crotches of the tree. 



As soon as the tree begins to grow in the spring the larva becomes 

 active, eats its way out of its winter home and bores into the new 

 growing twigs causing them to wither and die. Later generations of 

 the worm attack the fruit and from the two forms of attack much loss 

 may accrue to the orchardist. 



Destruction of the larvae in their winter burrows overcomes all 

 damage from these pests. This can be accomplished by spraying with 

 the lime-sulphur compound in the late winter or very early spring 

 when the buds are expanding. 



The Common Borer. An insect which has done vast injury in 

 this State is the "flat-headed apple borer" (chrysobothris femorata). 

 It affects chiefly apples, peaches and plums, etc., which have been 

 injured by sunburn. It is a pale-colored grub with a brown head, 

 the forepart of the body being greatly flattened. The matured beetle 



