The Mussel Scale 



IS 



The Mussel Scale or Oyster-Shell Back Louse. 



(Mi/tUaspis jMwionim, liouclie.) 



Xiiineroii.s erKiuiries are constantly being made l)y fruit-growers 

 and ganleuers concerning the Mussel Scale {MijtUaspU jMiiiorum). 

 There being no leaflets issued or other ready infonnation for fniit- 

 growei-s, the fuHowing notes have been prepared with a view to 

 meeting this want. 



The Mussel Scale is f«jund chiefly on apple, but also on pear, 

 currant, plum and wild Cratucijn.'i, such a.s the Hawthorn. I have 

 also found it al»undantly on Blackthorn in Devonshire. This 



c 



Fio 8. — UCSSEL SCALK (ilytiUuitia pomonim). 

 a, rpp«r : b, luwcr ■ur(ac« of 9 scale ; c, ^ icaJo. (Oreatly enUriged.) 



jxy?t, the worst scale insect we have in Great Britain, Ls found in 

 North Ameria», and ahso in Australia, New Zealand, and South 

 Africa, having l)een imj>orted on nursery stock. In this latter way 

 it is also largely distributed in this country. The necessity of 

 fumigating young stock l)efore planting is tiius rendered e.s.sential 

 and shouhl be done by all nui-ser)'men K'fore their stock is sent out, 

 A few scales may ea-sily escajH.* detection and so set up a lai^e 

 colony, to the detriment and even death of the tree. I know of no 

 district in Kngland wheix* this jK\st d<»e.s not (Kcur in greater or le.<w 

 abundance. Old trees an<l neglect»»d onhanls chiefly encourage it, 

 but y<»ung st<x;k sutler far m<»n' than old. 



This .scale insect is frt'<iuently taken for gpiwths on the bark. 



The scale is the pnxluct of a minute insect belonging to the 



