622 THE MONTHLY BULLETIN. 



THE MANZANITA SERICA. 



(Serica anthracina Lee.) 

 Ordei — Coleoptera. Family — Scarabaeidse. 



By E. O. EssiG, Secretary State Commission of Horticulture, Sacramento, Cal. 



In the latter part of April this office received a communication from 

 Mr. J. E. Hassler, County Horticultural Commissioner of El Dorado 

 County, stating that a certain fruit orchard in the foothills near Placer- 

 ville was being defoliated by a m.ysterious foe, the presence of which 

 could neither be found nor accounted for. He also stated that two years 

 ago the attention of this office was called to this condition, and that the 

 secretary of the Commission spent a day in the orchard, but was unable 

 to locate the trouble. At the request of Mr. Hassler the writer went to 

 Placerville with the idea of ascertaining, if possible, the depredator, 

 and to suggest means of control. On May 20th Mr. Hassler took the 

 writer to the orchard, and the damage to the trees, especially prune and 

 apple, proved serious. Practically all of the leaves were removed to the 

 stem. This work had continued for over a month, and some of the trees 

 had been killed during the past year because of the constant and com- 

 plete defoliation. 



Pig. 354. — Adult specimen of 

 the manzanita serica, Serica 

 anthracina Lee. Natural size. 

 (Original.) 



At first sight the work appeared to the writer to be that of the 

 scarabffiid beetles, and after two or three hours of diligent search a 

 single specimen was found actually eating the leaves of a prune tree. 

 This was followed up, and before we left we were able to find a dozen 

 actually doing the work ; so that we had discovered, beyond doubt, the 

 pest. 



Inasmuch as the principal damage was done to trees around the edges 

 of the orchard, the writer was led to believe that the beetle found was 

 of native origin and would probably occur on the wild shrubbery adjoin- 

 ing the orchard. This supposition was confirmed immediately by finding 

 the same beetle abundant on the manzanita and producing exactly the 

 same injury to this shrub as to the orchard trees. Great numbers were 

 found feeding upon this plant around the entire orchard. It was also 

 found feeding in less numbers upon the black oak, lupines and upon 

 Ceanothus sp. 



The least touch to the host plant would cause the beetles to drop 

 immediately to the ground and secrete themselves under any hiding 



