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METHODS OF CONTROL. 



The usual remedy for the protection of crops against the ravages of flea- 

 beetles, particularly the larger species, is to spray the plants with an arsenical 

 mixture containing either Paris Green or arsenate of lead, or with the ordinary 

 Bordeaux mixture alone. The latter acts as a deterrent. For most plants, Paris 

 Green may be used in the proportion of one-quarter of a pound to 40 gallons of 

 water, with one-quarter of a pound of freshly slaked lime. Such plants as have 

 coarse foliage, as the potato, will stand double this strength of Paris Green. Ar- 

 senate of lead, which has now come into such wide use may be used m the pro- 

 portion of from two to three pounds to 40 gallons of water. BoBth of these arsen- 

 icals may be applied in the above strengths in combination with Bordeaux mix- 

 ture. 



In the case of the Potato Flea-beetle, in experiments conducted at Ottawa, 

 the Bordeaux mixture used alone gave satisfactory results. When the beetles are 

 present in excessive numbers, it may be necessary to spray at least twice a week 

 or even every third day in order to get satisfactory results. Paris Green dry is 

 also a good remedy and may be used with land plaster, in the proportion of one 

 pound of the Paris Green to twenty pounds of the land plaster. This mixture 

 should be dusted upon the plants, preferably in the early morning when they are 

 covered with dew. The land piaster stimulates the plants and hastens their growth., 

 while at the same time the Paris Green kills the beetles. The Turnip Flea-beetle 

 especially is easily controlled by this remedy, which should be applied early in 

 the season, before the seed leaves, so important to the young plants, are destroyed. 

 When flea-beetles or other leaf-eating insects are found attacking cabbages, it is 

 inadvisable to use arsenical mixtures after the heads of the plants are half formed. 

 In spraying such plants, the mixture will adhere better if a "sticker" is added. 

 Such can be made by boiling together for about an hour, 2 pounds of resin and i 

 pound of sal soda (crystals) in a gallon of water. This is sufficient for 40 gal- 

 lons and, if used with Paris Green, a pound of fresh lime should be added. 



When setting out such plants as tomatoes, protection from flea-beetle attack 

 may be obtained by dipping them, except the roots, in a mixture of arsenate of 

 lead, using one pound in 10 gallons of water. 



In view of the fact that flea-beetles in the larval state feed upon the roots 

 of common weeds such as nightshades, thorn apple, lamb's quarters, pigweed, rag- 

 weed, etc., it is important that such weeds be pulled and burned. If this is done 

 about the middle of July, large numbers of the grubs will be destroyed. Weeds 

 along margins of fields, of course, should be kept down. It is a wise practice to 

 use land infested by such weeds for crops which are not attacked by the adult 

 flea-beetles. 



It is also important to remove from fields and gardens in the fall all remnants 

 of crops, such as cabbage stumps, leaves and tops of turnips, etc., and other re- 

 fuse which would serve as hibernating shelters for the adult flea-bettks. All such 

 refuse should be either ploughed deeply or carefully gathered up in piles and 

 burned. 



