8 FARMERS' BULLETIN 928. 



no likelihood of ever becoming dangerously numerous. The fluted 

 scale may gain an entrance into the orange groves, and under ant 

 attendance and other favorable conditions may become a serious 

 menace. There is probably little to fear from the black scale under 

 the climatic and other conditions which obtain in Louisiana. 



THE ANT AND ARMORED SCALES. 



The armored scales do not excrete honey dew or any similar liquid 

 attractive to ants and, contrary to the general belief, are not attended 

 by ants. They probably would become the prey of the ants if it 

 were not for their protective shield, or scale. Ant shelters, or " cow 

 sheds," sometimes occur over large and small groups of the armored 

 scales, but the number of scales covered is so exceedingly small that 

 it is unimportant. These shelters are erected for the protection of 

 the ants and not for the protection of the armored scales. The ant 

 does not disseminate a,ny of the armored scales of citrus or colonize 

 them upon new growth or new trees. 



The ants eat all insects that they cim capture except those supply- 

 ing honeydew, and therefore they disturb certain enemies of the ar- 

 mored scales, and perhaps occasionally feed on the eggs of some of 

 them. It therefore may happen that after two or three years of 

 heavy and constant ant attendance, an orchard that is never sprayed 

 or fumigated for the control of the armored scales may become more 

 heavily infested by these scales than if ants were not present. Se- 

 vere and injurious scale infestations may develop in a single year, in 

 unsprayed orchards free from ants, as the natural enemies of the 

 scales are not effective control agents. The injury caused by these 

 scales, therefore, can not be prevented by destroying the ants. Direct 

 control measures against these scales must be adopted and persist- 

 ently practiced if orange growing is to be made profitable. 



There are four important and destructive armored scales of orange 

 trees in Louisiana the purple scale, 1 chaff scale, 2 long scale, 3 and 

 white scale. 4 The purple and chaff scales are by far the most numer- 

 ous, generally distributed, and injurious, and for a long time have 

 been among the leading citrus pests of Louisiana. The infestations 

 of the armored scales are sometimes more severe where ants occur, 

 sometimes more so where they do not, and are almost certain to be 

 severe in untreated groves. These scales are more numerous on the 

 present-day budded orange trees of Louisiana than they ever were in 

 the seedling trees which formerly were common and which still are 

 grown in large numbers in Cameron Parish, but this is due to the 

 greater resistance of the seedling trees to scale infestation. 



1 LepidosapJies beckii (Newm.). 3 Lepidosaphes glov erii (Pack.). 



2 Parlatoria pergandei Comst. * Chionaspis citri Comst. 



