a wn 
Daffodil bulbs treated with vapor heat respond to forcing.—-R. 
Latta, Sumner, Wash., summarizes results of forcing tests of narcissus 
bulbs that have been treated with vapor heat as follows: "(1) Bulbs 
treated with vapor heat for the following durations and temperatures 
when forced made satisfactory production of flowers: 2 hours at 111° F.; 
3 hours at 111°; 4 hours at 108°; 6 hours at 108°; 8 hours at@lOGo sais 
treatments for 3 hours at 111° and for 6 hours at 108° showed slightly 
more effect than for 2 hours at 111°, 8 hours at 106°, or 4 hours at 
108°; (3) Emperor, Victoria, and Beppy will tolerate later treatments 
than Golden Spur, King Alfred, and Bernardino. The data on this report 
do not indicate the exact time limits for successful treatment; (4) for 
satisfactory forcing the bulbs should be adequately cured before treat— 
ment." 
Liothrips vaneeckei Priessner controlled by HCN fumigation.—-R. 
scopp, Sumner, reports that "Tests using sodium cyanide at the dosages 
of one third ounce and two thirds ounce per 100 cubic feet for 2 hours 
gave 100 percent mortality of larvae, pupae, and adult thrips. Two 
thirds ounce per 100 cubic feet for 1 hour also resulted in 100 percent 
mortality of the same forms. Eggs were not available for these tests." 
Derris effective against cabbage worms.--C: B. Wisecup, Sanford, 
Fla., reports: "In laboratory tests in the month (April), the 50-50 pyre— 
thrum—flour mixture continued to give very good kills of celery leaf—tier 
larvae (Phlyctaenia rubigalis Guen.). Derris powder was not effective 
as a contact dust for the celery leaf-tier or the celery looper (Auto— 
grapha falcifera Kby.), but was very effective for the imported cabbage 
worm (Ascia rapaeL.). As a stomach poison derris dust was more effec- 
tive than lead arsenate for the cabbage worms, but arsenic was more ef- 
fective as far as the southern armyworm (Prodenia eridania Cram.) was 
concerned. In all cases, however, the larvae did not feed sufficiently 
to injure the treated leaf surfaces. Derris spray, mixed with an equal 
quantity of acetone and diluted to 1 part in 250 parts of water, was 
fairly effective as a contact insecticide for the cabbage worms. For the 
cabbage worms, these tests indicate that derris is superior to lead arse— 
nate, both as a spray in the concentration used, and as a dust. The dust, 
guaranteed to contain 3 percent rotenone, was most effective. The rotenone 
content of tht extract has not been determined," 
Tobacco plants uninjured by flea—beetle insecticides.--F. S. Cham— 
berlin, Quincy, Fla., reports that experiments to determine the toxic-— 
ity of "diluted barium fluosilicate, synthetic cryolite, natural cry- 
olite, and ground derris root" in tobacco seed beds "have been contin-— 
ued. All of these materials were apparently very nearly harmless to 
the tobacco plants. Natural cryolite appeared to be Slightly more toxic 
than either barium fluosilicate or synthetic cryolite. Tobacco dust 
proved to be the most satisfactory of the various carriers tested, while 
tale was found to be unsuited for this work." 
