I062 IXSlvCTS ETC. INJURIOUS TO VARIOUS CROPS 



Akurites triloba ; Agave americana ; Cineraria cruenta \Citrus medica var. 

 gcnuina ; Cokus Blumei ; Epiphyllum spp. (crab cactus) ; Cfoton Tigliiim ; 

 Cordyline terminalis (dracaena) ; ferns ; fig tree ; Flacourtia sepiaria ; Fuchsia 

 spp: ; Erythea edulis (Guadeloupe island palm) ; Psiditim Guajava (guava) ; 

 lemon tree, mango tree ; 1 pomoea Boiia-nox ; Nephrodium amplum ; Neriutn 

 Oleander ; Opuntia spp. ; Phormium knax var. variegatum ; plum tree ; 

 Cycas revoliita ; Platyceriimi spp. ; Stangeria schizodon ; Skrculia Gregori ; 

 Cypetns alkrmfolius ; Zamia spp. Chiefly tropical and subtropical species 

 introduced into California as ornamental plants. 



Cordyline krminalis (dracaena) is chiefly injured by the adults, which 

 sometimes gather in large numbers on the terminal buds and prevent 

 growth. 



Among the natural enemies of these species of Pseudococci:s in Cali- 

 fornia, there are : i) Svmpherobiiis californicus Banks (brown lacewing); 

 the female lays its eggs on the leaves and the fruits of the infested citrus 

 plants, and the laivae emerging, like the adults, destroy a large quantity 

 of Pseudococctfs ; 2) Leucopis bella Lcew, the only reallj^ effective natural 

 enemy of P. citrophilns ; 3) Cryptolaemns montronzieri jMuIs. : spreads 

 very slowly and with difficulty, and can only live in a few very limited coast 

 localities where it finds the conditions of moisture and temperature needed 

 for its growth ; 4) Chrysopa californica Coq. (green lacewing) ; its larvae 

 attack the larvae and adults of Pseudococcus ; 5) Scymnus guttulatus 

 Lee. and .S. bipunctatus Kugel : the latter was import ed from the Philip- 

 pines in igio and is now found in the counties of Ventura and vSanta Bar- 

 bara ; (>) S. marginicollus and 5. scrdidus Horn : the latter is the most effec- 

 tive species of Scvmmus in controlling Pseudococcns ; 7) Chrvsoplatvcerous 

 spkndens How. , introduced from the Philippines into the t ounty of vSan Diego 

 and at present spread throughout Southern California. 



Fumigation with hydrocj^anic acid, and applications of various anti- 

 fungus preparations, may give good results, but the best have been obtained 

 by simple jets of water under high pressure at the rate of 44 to 66 gallons 

 of water per plant. 



836 -The Woolly Whitefly (/I /ewro^Ar/xu5 Howard/) in Florida Citrus Planta- 

 tions. — Watson J. R. in University o> Florida, A'^rituHural Experiment Station, I-iulk-lin 

 Xo. 126, pp. 81-10.2. Tallahassee, Fla., 1013. 



Akitrothrixus howardi Ouaintance, which was very probably import- 

 ed from Cuba, was discovered for the fiist time in Florida in the neigh- 

 bourhood of Tampa, in the autumn of 1909. In 1914 it had already reached 

 the counties of Hillsborough, Pinellas, Manatee, Polk and De Soto, and will 

 soon end in becoming common in all the citius plantations of Florida. 



Akicrothrixus causes damage in three ways to the plants attacked : 

 t) removal of juice from the tissues, causing the withering of the plant ; 

 2) secretion of a honeydew which covers the leaves and fruits and forms 

 a good medium for the growth of Meliola Camelliae and other fungi hin- 

 dering the functions of the leaves and rendering washing of the fruit necess- 

 ary ; 3) the colonies of Akurothrixus are a centre of attraction for the 

 " purple scale " {Lepidosaphes bcckii) so injurious to citrus plants. 



