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tliemselves into a compact ring, oa tlie under sides of the leaves, wlien not feeding. 

 When nudisturbed they are covered with a pretty close coat of very white down ; 

 some, as you will see, are without the down. They look like bird-droppings. The 

 locality is a very shady woody ravine where the sunshine can not penetrate. In the 

 box there is a small larva, found on a plant not common, in the same place. — [J. G. 

 Barlow, Cadet, Mo., September 10, 1888. 



Eeply. — * * * The species is Emphytus iestaceus, being nearly allied to the 

 Strawberry Saw-fly. The climbing plant which you enclose is Polygonum dumeioi'um. 

 — [September 14, 1888.] 



Oscinis sp. on Chrysanthemum. 



Some on3 sends me a specimen of Chrysanthemum Jrutescens, with an insect pest that 

 seems new to me. * * * — [Thomas Meehan, Germantown, Philadelphia, Pa., Jan- 

 uary 12, 1887. 



Eeply. — * * * The insect infesting Chrysanthemum is a Dipterous leaf-miner 

 of the genus Oscinis and is probably an undescribed species. I have received the 

 same thing within a few days from Mr. Charles Henderson. Certain of the fli'^s had is- 

 sued on the way, so that it is now too late to do much in the way of hand-picking, 

 which is the only available remedy. When another brood appears the infested leaves 

 should be picked otf and burned. In this way the pest can be very readily held in 

 check. — [January 14, 1887.] 



Ants destroying young Maples in Nebraska. 



There is a small black ant that is destroying all of the young rock or sugar maple 

 trees which have been grown from seed planted this summer in the western part of 

 Nebraska. The seeds were phiuted on new land, opened last spring. I will give you 

 a description of how the ants attack the young trees and how tlie trees are atfected. 

 They attack the trees just above the ground. Tlie trees look as if they were stung. 

 The bark turns brown as if it was decaying. There is a ring formed around the tree 

 about one-eighth inch wide, and the young tree dies when the ring is completed. * "" 

 — [B. F. Blythe, Diller, Jetlerson County, Xebr., July 16, 1886. 



Reply — * * * We should like very much to receive specimens both of the ant 

 and its work on the young sugar maples. The efficacy of any remedy which you may 

 try depends altogether upon the trouble and expense to which you are willing to go. 

 The best preventive will of course be a broad band of bright tin fastened securely 

 around the base of the tree. Search should be made for the colonies, which you can 

 destroy by the use of bisulphide of carbon, which is poured in small quantities into 

 the nest. Naphthaline in the form of a crystalline powder stirred in and about the 

 liills is very effective in breaking up colonies. When they have begun to attack a 

 tree it is with extreme difficulty that they can be permanently driven off. 



Pyrethrum dusted upon the tree and scattered about its base kills all the ants with 

 which it comes in contact and affords a temporary relief, but its effects are not lasting* | 

 Coating with shellac and binding tbe trunk with a band of tar cannot.be relied upon 

 to keep them off" permanently. A broad band of rabbit fur, tied around the trunk 

 with the hair downwards, is effectual iu preventing their ascent. A still more simple 

 and almost as effective one is a barrier of chalk. This is applied by rubbing a lump j 

 of raw chalk over the bark around the tree to make a band about 8 inches wide, and ' 

 completely encircling the trunk. In attempting to cross such a band the ants nearly ' 

 always slip and fall to the earth. Thisdevic.^ isnot permanent, and retiuires frequent • 

 renewal on account of the effect of dews at night and of rains. Very often soft clay,^ 

 Fuller's earth, or talc may be substituted for the chalk, but in all cases must be ap 

 plied by rubbing on from a dry lump. Good results cannot be obtained by using anj 

 of these snbstaucos inpovs^der, dried, or as a whitewash applied with a brush. — [Jnly 

 22, 1886.] 



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