1929] 
SERVICE AND REGULATORY ANNOUNCEMENTS 
71 
For the treatment to be successful the temperature of the soil during the 
48-hour period of treatment should never fall below the minimum temperature 
for the dosage being used, as shown in Tables 6 and 7. A map has been 
prepared of the different townships of the Northern and Middle Atlantic 
seaboard States, based upon data from the United States Weather Bureau, 
and which indicates the probable dates when the soil temperature at a depth 
of 6 inches will not fall below 40° F. The inspector should obtain from the 
Camden office information on this point with respect to the area in which he is 
working. The dates for the minimum temperature are shown in Table 8. 
Treatment may be started on the date given in the first column, and the 
dosage should be changed accordingly. 
Table 8. — Minimum temperature dates 
Zone No. 
Spring temperatures 
Autumn temperatures 
40° F. 50° F. 
60° F. 
60° F. 
50° F. 40° F. 
1 
Mar. 4 | Apr. 19 May 19 
Mar. 11 ...do. do 
Oct. 11 
—do 
j Oct. 4 
...do..... 
Sept. 27 
...do 
Sept. 19 
Sept. 11 
Aug. 27 
Aug. 19 
Nov. 4 , Dec. 11 
...do Do. 
Oct. 27 Nov. 27 
...do Do. 
Oct. 19 Nov. 19 
...do Do. 
Oct. 11 Nov. 11 
2 
3 
Mar. 19 Apr. 27 
Mar. 27 !...do 
Apr. 4 Mav 4 
May 27 
...do 
June 4 
4 
5 
6 
Apr. 11 
Apr. 19 
Apr. 27 
May 4 
May 11 
May 11 June 11 
May 19 June 27 
...do ...do 
May 27 t July 11 
June 4 1 Julv 1 
7 
8 
Oct. 4 
Sept. 27 
—do 
Nov. 4 
Oct. 27 
Do. 
9 
10.. 
The inspector must keep an accurate record of the minimum soil temperatures 
at a depth of 6 inches throughout the season. An accurate thermometer gradu- 
ated in at least single degrees must be used. The temperatures must be taken 
between 6 a. m. and 8 a. m. each morning in order to obtain the minimum tem- 
perature. This must be done in the nursery plots or beds from which the 
plants are being taken. If the soil temperature in the spring has not reached 
40° F. by the date in column 1, treatment must be delayed until this point is 
reached. 
Preparation of plant for treatment. — Remove all weeds and debris from the 
soil about the plant. Tie low hanging branches so they will not dip into the 
solution. Level the soil. After the size of the mass of soil to be lifted has been 
determined, place a galvanized-iron collar about the plant and force it 3 inches 
into the soil. The size of the collar to be used is shown in Tabic 4. Firm the 
soil carefully on each side of the metal. 
Application. — Measure the diameter of the collar, find from Table or 7 the 
number of gallons of water and the cubic centimeters of miscible carbon 
disulphide required, and mix with a stick. Pour into the collar, avoiding splash- 
ing or unnecessary disturbance of the soil. 
Period of treatment.— The collar and the soil musl not be disturbed for 48 
hours. The plant must be dug between two and five days after treatment. 
Handling after treatment.- -The plant may he dug and handled according to 
the usual nursery practice, except that no soil outside (4* the collar inn-: be- 
taken up with it. 
Conditions unfavorable for treatment. — (1) On hillsides having a SlO] 
more than 1 inch to 10 inches it la practically Impossible to distribute the 
tion uniformly over the surface. (2) In stony land it may be impossible to 
place the collars in the soil. (3) Hardpan or B high water table may cause 
the solution to Boak too slowly into the ground, if the solution doi^ not pene- 
trate within five hours treatment will probably be ineffective, i n Excessively 
free drainage, mole holes, or plant- that have been recently transplanted may 
Cause abnormally rapid penetration of the solution. If 'the solution disap- 
pears within 10 minutes after application the treatment may be unsatisfactory. 
i. diki | 1 1" vs POB i ia:\ i Mi'.N i or mi i i ia\ i ei LNTfi 
The disinfection of soil about the roots of nursery plants for the puxpo 
destroying the immature stages of Japanese and Asiatic beetles is very difficult 
because the insects are in close proximity to valuable living plants which may 
