= 
EXPERIMENTS WITH SPRAY SOLUTIONS FOR GREEN LOGS. 0 
materials recommended by various correspondents or suggested by 
the forest insect personnel. Dr. J. IKK. Haywood, chairman of the 
Insecticide and Fungicide Board, United States Department of 
Agriculture, also gave some very interesting suggestions. 
These experiments are to be considered as only of a preliminary 
character. The objects were chiefly to determine the requisites of 
an effective spray and to study the behavior of the different types 
of insects in relation to various treatments and methods of applica- 
tion, as well as to find an effective spray. 
The solutions were tried principally on two kinds of wood—pine 
and ash—although occasionally hickory, juniper, and oak were used. 
The wood was cut at a time to give the most favorable condition 
for insect attack—hickory and juniper about January 1, pine and 
ash about March 15. It was treated immediately or held in a wire 
insectary until treated. The individual pieces of wood used were 
3 feet long and averaged from 6 to 10 inches in diameter. 
Insects of all types were represented in the tests. The following 
were the most abundant and economically the most important: 
Neoclytus erythrocephalus Fab. on ash and hickory, Xylotrechus 
colonus Fab. on oak and hickory, Asemuwm moestwm Hald. on pine, 
Cyllene pictus Drury on hickory, and Hylotrupes ligneus Fab. on 
juniper—all of type 1; Wonohammus scutellatus Say and J. titillator 
Fab. on pine—both of type 2 (no species of type 2 on other woods) ; 
various species of Ips, Phloeosinus, and Hylesinus on pine, juniper, 
and ash, respectively—of type 4; various species of ambrosia beetles 
on pine and oak of type 3. 
From the foregoing it is seen that pine was tested against all four 
types; ash against types 1, 3, and 4; hickory against type 1; juniper 
against types 1 and 4; and oak against types 1 and 3. Owing to the 
seasonal variations in the abundance of the various species of insects 
the tests were not conclusive every season. For example, in 1918 and 
1919 Monohammus was very abundant and attacked all the controls 
as well as many treated woods, while in 1920 very few were present 
and not all control logs were attacked. Again, in 1918 Hylesinus 
(type 4) in ash was abundant, though in 1920 very few of the con- 
trol] logs were attacked. Every year, however, some one type was very 
abundant on all species of wood used. 
The flight period of these insects has a certain bearing on the re- 
sults, as those species flying late in the season found the logs after 
they were exposed to weathering for a month or more. Most of the 
treatments were made about April 1, or 15 days before the flight of the 
first insects, and unless otherwise stated this time of treatment is to 
be inferred. With certain materials treatments were made also on 
June 1 at the time of the first flight of some other species. The flight 
periods are given in Table I. 
102230—22 
