850 EXPERIMENT STATION RECORD. 



ried out with various cultural and remedial measures for the control of these 

 two root maggots. Cultural methods include the destruction of rubbish about 

 fields where the crops are grown and the disinfection of sheds or crates in 

 which the crops are stored. It has been found better to plant the onion sets 

 in late September or October rather than in August or early September. A good 

 fertilizer should also be applied, and the ground should be kept thoroughly 

 stirred about the gi-owing plants, whether cabbage or onions. 



Among the specific treatments applied to the control of these pests a mixtin-e 

 of carbolic acid and lime containing 1 tablespoonful of carbolic acid and enough 

 lime to make a paste in a gallon of water gave the best results. Considerable 

 benefit was also noted from the use of tarred paper cards alxnit the plants and 

 kerosene, powdered tobacco, white hellebore, and dry lime. 



Where an infestation has ah*eady taken place, direct destructive measures 

 may be used, such as carbon bisulphid, carbolic-acid emulsion, and a decoction of 

 hellel)ore. 



Two new pests of carrots, C. Borner (Arh. K. Biol. Anst. Land u. Forstiv., 

 5 {1906), 'No. 5, pp. 2S2-292, pgs. 11). — In some localities considerable injuries 

 are reported from the attacks of Cevtorh inn-hUlhis fcrmiiiatus and Phytomiiza 

 (icniciilata, both of which are described in detail, with notes on their life 

 history. 



An insect pest of water cress, C. Cateub (Rev. Hort. Beige, 33 (1907), No. 1, 

 pp. IJf, 15). — The larvffi of a tiy (Hi/drcllia ranunculi) are reported as mining 

 in the substance of the leaves of water cress, thus ruining their appearance 

 and suitability for table use. No satisfactory remedy has been devised for the 

 pest. 



The spring canker worm, H. A. Gossard and J. S. Houser {Ohio Sta. Circ. 

 6.5, pp. 7, ^'f/s'. 8). — The life history of spring canker worm is briefly outlined. 

 In controlling this insect in orchards the fruit grower should depend chiefly 

 on the proper application of bands and spraying with arsenate of lead or Paris 

 green in I'.ordeaux mixture or in water. 



Whitefly conditions in 1906. The use of the fungi, E. W. Berger {Florida 

 >S7rt. Bui. SS, pp. 49-85, pis. 3). — Parasitic fungi have been widely used in 

 Florida in combating the whitefly. Success was had in 98 per cent of cases 

 from spraying the spores of the fungi on trees or by attaching leaves carrying 

 the fungus to trees. In this work the author used Ascliersonia aleyrodes, A. 

 flavo-citrina, the brown fungus, and Spha'rostible coccophila. The spores of 

 the brown fungus have not yet been discovered, hence they can not be used in 

 spraying on the trees. It has been found that in the other species the spores 

 retain their vitality for a month, or perhaps longer. 



All of the three first-named species of fungi thrive throughout Florida, but 

 a humid atmosiihere is essential for their growth. Apparently the best time 

 for starting the fungi in trees infested with the whitefly is from Maj^ to August. 

 Repeated plantings of the fungus should be made to insure success. 



In badly infested localities it is recommended that trees along roadways 

 should be trimmed high to avoid the distribution of the whitefly by carriages 

 brushing against the branches. The whitefly feeds on a number of trees, includ- 

 ing Cape Jessamin, chinabeny, umbrella tree, prickly ash, trifoliate orange, 

 and others. Where these trees are of no value and infested they should be 

 cut down and burned. If it is desirable to use insecticides against the wliitefly, 

 spraying or fumigation should preferably be done from December to February. 



The gipsy moth and how to control it, L. O. Howard {U. S. Dcpt. Agr., 

 Farmers' Bui. 215, pp. 22, figs. 7). — Historical notes are given (m the distribu- 

 tion of the gipsy moth in Europe, its introduction into this country, and its 



