264. TWENTY-FIFTH ANNIVERSARY REPORT. 
the employment of poisons, but the opinion was quite prevalent that 
arsenicals, applied strong enough to materially check the insects, 
seriously injured the willows, which discouraged their use. To 
protect the willows, the growers relied largely on “ bug catching ” 
machines, which, while effective on larger plants, were unfortunately 
not satisfactory for the young willows in the early season, which 
were often ruined. At the outset, it seemed that the use of arsenical 
poisons would solve the problem, and so during 1896 and 1897, 
tests were made at Liverpool to determine the strength of poison 
that could safely be used on willow foliage with efficient results on 
the insects. Some experiments were also made to ascertain the 
comparative cost of spraying as compared with the average ex- 
pense of operating the machines. Investigations were also made 
to ascertain the life history of the insect. The results of the field 
tests were gratifyingly in favor of spraying both as a means of 
protecting young willows and for its economy, as the cost of spray- 
ing one acre was but $2.58 as compared with an expenditure of 
$4.05 required by the use of machines. 
To assist growers in affording better protection to their planta- 
tions, Bulletin No. 143 was issued in 1898, which called attention 
to the habits of the beetle and gave directions for the use of arsen- 
ical poisons for the treatment of willows. 
ONION CUTWORM. 
(Euxoa messoria Harris.) 
In 1905 the attention of the Station was called to the onion fields 
of Orange County which were being ravaged by this cutworm. 
This destructive insect also appeared in 1896 and was computed 
to have destroyed at least 46 per ct. of the onion crop, besides in- 
juring severely many other garden and market vegetables. During 
these years, observations were made on the life history and habits 
of this species, and several lines of treatment were tested by the 
Station. When the cutworms commenced their work on the onion 
fields, it was found that the caterpillars migrated from the margins 
of ditches and driveways, so tests were made of various remedies 
to determine their value for the protectien of the crop and their 
effectiveness in checking the progress of the worms from the ad- 
jacent fields and swampy neglected lands into the cultivated areas. 
Comparative experiments*! were made of the resin-lime mixture, 
* Rpt. 15:628-635 and Bul. 120. 
