UNITED STATES DEPARTMENT OF AGRICULTURE 
BULLETIN No. 774 
Coniribution from the Bureau of Entomology 
L. O. HOWARD, Chief 
Washington, D. C. PROFESSIONAL PAPER — April 28, 1919 
LIFE HISTORY AND HABITS OF THE MEALY 
PLUM APHIS. 
By W. M. Davinson, Scientific Assistant, Deciduous-Fruit Insect Investigations. 
CONTENTS. 
Page. Page. 
ri pitinw sno ca.e =< - Soseoncosstesesete 1 | Biology—Continued. 
Hosts and migratory habits...-......-.-.-.-. 1 The summer wingless forms. ..........-. il 
LETT Ae Sd ele SE Sa eae a 2 Tho fall forms ges ec. ae Sasnsnite oie neretoas 12 
SLEDS. 22 slop et oo eeienbe oe omedsoldgbaeos oil Natunalienemies seen ecem c= cies els seis aia M4 
RNY sae see oe se = seo ake Ss ee eee eal S558 3 | Control suggestions ./-22./5.2/22-.-.2-2-225. 15 
DUPED GRE: — 3 RRB SRB Ss Seppe Seo c ne oreeoes Sui Summary ee. co. as Usa. ee netace see cicee 15 
The stem mother...... SmenenoceeoOOse 56 Sh | PLATEAUS CLtCM sm. icine eee e aces 16 
Phe spriae forms. . 555. e ts ass sess 5 
The mealy plum aphis (Hyalopterus arundinis Fabricius) has been 
recognized for many years as an enemy of plums, prunes, and to a 
lesser extent apricots in California. Since 1913 it has been espe- 
cially severe in some regions, notably those in which artificial control 
for the pear thrips (Yaeniothrips pyri Daniel) was not practiced. 
ORIGIN. 
The insect is European in origin, having been first described in 
1794 by Fabricius. In North America it is widely distributed. <Ac- 
cording to Lowe (3)1 it is present in Australia and New Zealand, Van 
der Goot (2) reports it from Java, while the United States Bureau 
of Entomology has records of its occurence in Japan. Specimens 
in the writer’s collection taken on Arundo in Peru, by Mr. E. W. 
Rust, late of the Bureau of Entomology, appear to belong to this 
species but the lack of winged forms prevents certain determination. 
HOSTS AND MIGRATORY HABITS. 
In California plums and prunes of the domestica type are the 
favorite hosts, but apricots and Asiatic types of plums and rarely 
1 Bigures in parenthesis refer to “‘ Literature cited”’ on the final page of the bulletin. 
98008°—Bull. 774—19 
