338 STATE HORTICULTURAL SOCIETY. 



a very little laud-plaster and hellebore. Still another patented humbug 

 found its way into the market last year. It was claimed that if seed 

 potatoes were treated with "Siebner's Potato Bug Exterminator Com- 

 pound," the bugs would be prevented from destroying the vines, and 

 the quality and quantity of the crop would be improved. It seems almost 

 needless to add that careful tests by two experiment stations showed 

 that this compound was entirely worthless for the purpose recommended. 

 The lessou to be learned from these illustrations is to exercise a little 

 common-sense when approached with a panacea for all the ills to which 

 your plant may be heir, even though backed by the testimonials of 

 hundreds of sufferers. 



The immortal words of Walsh, written in 1867, are as applicable today 

 as then: ''Long live King Humbug! He still feeds fools on flapdoodle!" 

 It is true that some of the patented insecticides have merit, but usually 

 what little they have is derived from the proportion of some of the 

 standard insecticides used in their preparation. Most of them are simply 

 adulterations of standard, unpatented, and less expensive insecticides. 

 Wait until a substance has been thoroughly tested by several of the 

 experiment stations and has received their unqualified approval before 

 you invest in it. 



The "acme of perfection" has not yet been reached in our standard 

 insecticides, like Paris green, London purple, kerosene emulsion, etc. 

 Experimenters are still searching for something cheaper or more effective 

 than these. In the magnificent fight which the state of Massachusetts 

 is making against the gypsy moth, almost every poisonous substance 

 which chemists can concoct or suggest is being tested. It has been dem- 

 onstrated that one of the caterpillars of this insect may withstand 

 uninjured an amount of arsenic, in proportion to its weight, equivalent 

 to 12^ times the fatal dose for a man in proportion to his weight. Arsenic 

 has also been found in the bodies of pupse, and even in female moths, 

 reared from poisoned gypsy moth caterpillars. 



" Gypsine " or arsenate of lead is a very promising arsenical compound 

 which has been recently brought out in the work of the gypsy moth com- 

 mittee. As yet, horticulturists have used it but little, but where it is 

 desirable or necessary that an insect quickly get a large dose of poison 

 to facilitate its death before it can do much damage, it is proving a valu- 

 able addition to our list of poisonous insecticides. It has been used quite 

 extensively against the elm-leaf beetle in the eastern states. It is very 

 doubtful if it will ever take the place of Paris green for general use, 

 although it costs less per pound and will not burn the foliage even when 

 used ver}^ strong. It has to be used three or four times as strong as Paris 

 green to get the same effect, thus rendering the final cost about the same. 

 From experiments made during the past summer on gypsy moth catcrpil- 

 • lars, the indications are that another arsenical compound known as 

 barium arsenate is the most successful poison that has yet been tested. 

 This substance is not yet in shape for recommendation in ordinary use, 

 and its prei>aration is somewhat complicated. 



A modification of Paris green, known as arsenite of copper, which is 

 less expensive and more easily kept in suspension, has recently been 

 tested by Mr. Marlatt of the United States department of entomology, 

 and- he reports it equally effective with Paris green. If its apparent 



