INSECTS. 121 



been the moat common practice, or, wliat is better, over a broad 

 belt of clay-n:ortar, or on strips of old canvass or of strong paper, 

 from six to twelve inches wide, fastened around the trunk with 

 strings. The tar must be applied as early as the first of November, 

 and perhaps in October, and it should be renewed daily as long as 

 the insects continue rising ; after which the bands may be removed, 

 and the tar should be entirely scraped from the bark. When all 

 this has been properly and seasonably done, it has proved effectual. 

 The time, labor, and expense attending the use of tar, and the in- 

 jury that it does to the trees when allowed to run and remain on 

 the bark, have caused many persons to neglect this method, and 

 some to try various modifications of it, and other expedients. Among 

 the modifications may be mentioned a horizontal and close-fitting 

 collar of boards, fastened around the trunk, and smeared beneath 

 with tar ; or four boards, nailed together, like a box without top or 

 bottom, around the base of the tree, to receive the tar on the out- 

 side. These can be used to protect a few choice trees in a garden, 

 or around a house or a public square, but will be found too expen- 

 sive to be applied to any great extent. Collars of tin-plate, fas- 

 tened around the trees, and sloping downwards like an inverted 

 tunnel, have been proposed, upon the supposition that the moths 

 would not be able to creep in an inverted position, beneath the 

 smooth and sloping surface. This method will also prove too ex- 

 pensive for general adoption, even should it be found to answer the 

 purpose. A belt of cotton-wool, which it has been thought would 

 entangle the feet of the insects, and thus keep them from ascending 

 the trees, has not proved an effectual bar to them. Little square 

 or circular troughs of tin or of lead, filled with cheap fish oil, and 

 placed around the trees, three feet or more above the surface of the 

 ground, with a stuffing of cloth, hay, or sea-weed between them and 

 the trunk, have long been used with good success ; and the only 

 objections to them are the cost of the troughs, the difficulty of fixing 

 and keeping them in their places, and the injury suffered by the 

 trees when the oil is washed or blown out and falls upon the bark. 

 These troughs ought not to be nailed to the trees, but should be 

 supported by a few wooden wedges driven between them and the 

 trunks. A stuffing of cloth, cotton, or tow, should never be used ; 

 sea-weed and fine hay, which will not absorb the oil, are much 

 better. Before the troughs are fastened and filled, the body of the 

 tree should be well coated with clay-paint or white- wash, to absorb 

 the oil that may fall upon it. Care should be taken to renew the 

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