- 492 - 
PARKER, T. (2105) 
1923. THE SUPPRESSION 01 INSECT PESTS AND FUNGOID DIS^AS^S. 3. THE 
FUMIGATION OP COivikERCIiiL GLASSHOUSES IN THE GROWING SEASON. Bull. 
Bur. Bio-Tecli. ii, 9 pp. 21-26. [Abstract in Rev. Appl. Ent. 
(A) 11: 307. 1923.] 
Against aphids nicotine is the most effect ive medium for use 
under glass. It should be applied as a dust with a special vaporizer, 
as owing to the high boiling point of the liquid its rate of evapora- 
tion in an ordinary hothouse is much too slow to be effective. 
Reference is made to the burning of paper impregnated with nicotine. 
WEIGEL, C. A., and SASSCEE, E. R. (2104) 
1923. INSECTS INJURIOUS TO ORNAMENTAL GREENHOUSE PLANTS. U. S. Dept. 
Agr. Farmers 1 Bull, 1362, 81 pp., illus. 
Tobacco' extracts or nicotine solutions are very generally 
used for the control of man soft-bodied sucking insects. The 
volatile or "free" nicotine as e, liquid is largely used for fumi- 
gation by painting it on the hot steam pipes or by vaporizing it 
over lamps. Non-volatile nicotine solutions, made from 40 percent 
nicotine sulphate, are also briefly described (p. 6). Nicotine 
oleate and kerosene nicotine oleate are briefly discussed (pp. 6-7). 
Tobacco dust and nicotine oust are described (pp. 8-9) . 
Tobacco fumigation is employed by florists for the control of 
plant lice, thrips, and whiteflies, when it is not convenient to 
use hydrocyanic acid gas. Tobacco stems have been used extensively 
in tiie past but have now been discarded because of the difficulty 
surrounding their use. At present the burning of standard tobacco 
papers or the painting of one or more hot steam pipes with vola- 
tile nicotine solutions is a very convenient and efficient method 
oi producing a smudge (p. 12). 
Tobacco, in one or more forms, is used against the following 
insects found in greenhouses; inflaitefly ( Trialeurod.e s vaporariomm 
tfestw.) - 40-percent nicotine solution or nicotine oleate may be 
employed, preferably preceded oy one or two tooacco fumigations (p. 21). 
Narcissus or daffodil fly (kgrodon equestris Pab.), lesser bulb fly 
(Eumerus strigatus pallon) , and bulb mites (Rh izoglyphus hyacinth i 
Boisd. and R. rhizop hagus Banks) - immerse bulbs in solution of 40 
percent nicotine-sulphate (1 to 400) or nicotine oleate (pp. 22, 
23, 25) heated to 122° P. 
Onion thrips (Thrips t abaci Bind.) - tooacco smudges produced 
from nicotine solution or preparations impregnated with it; spray- 
ing with nicotine solutions; or dusting with either superfine tobacco 
dust or nicotine dust (p. 26). 
Chrysanthemum midge ( Dia.rthronomyia hypogaea Low) - nightly 
furni, tiori with tobacco papers, or spray with nicotine solutiOxis 
(p. 32). 
