122 THE PESTS OF THE FARM. 



oil as often as it escapes or becomes filled with the insects. These 

 troughs will be found more economical and less troublesome than 

 the application of tar, and may safely be recommended and em- 

 ployed, if proper attention is given to the precautions above named. 

 Some persons fasten similar troughs, to contain oil, around the outer 

 sides of an open box enclosing the base of the tree, and a projecting 

 ledge is nailed on the edge of the box to shed the rain ; by this 

 contrivance, all danger of hurting the tree with the oil is entirely 

 avoided. Let a piece of India rubber be burnt over a gallipot, into 

 which it will gradually drop in the condition of a viscid juice, which 

 state, it appears, it will always retain. Having melted the India 

 rubber, let a piece of cord or worsted be smeared with it, and then 

 tied several times round the trunk. The melted substance is so 

 very sticky, fchat the insects will be prevented, and generally cap- 

 tured, in their attempts to pass over it. It has been suggested that 

 the melted rubber might be applied immediately to the bark with- 

 out injuring the trees. A little conical mound of sand surrounding 

 the base of the tree is found to be impassable to the moths, so long 

 as the sand remains dry ; but they easily pass over it when the 

 sand is wet, and they come out of the ground in wet, as often as in 

 dry weather. 



Some attempts have been made to destroy the canker-worms 

 after they were hatched from the eggs, and were dispersed over the 

 leaves of the trees. It is said that some persons have saved their 

 trees from these insects by freejy dusting air-slacked lime over them 

 while the leaves were wet with dew. Showering the trees with 

 mixtures that are found useful to destroy other insects, has been 

 tried by a few, and, although attended with a good deal of trouble 

 and expense, it may be worth our while to apply such remedies 

 upon small and choice trees. ^ mixture of water and oil-soap (an 

 article to be procured from the manufactories where whale oil is 

 purified,) in the proportion of one pound of the soap to seven gal- 

 lons of water has been used ; this liquor, when thrown on the trees 

 with a garden engine, will destroy the canker-worm and many other 

 insects, without injuring the foliage of the fruit. Jarring or shaking 

 the limbs of the trees will disturb the canker-worms, and cause 

 many of them to spin down, when their threads may be broken 

 off with a pole ; and if the troughs around the trees are at the same 

 time replenished with oil, or the tar is again applied, the insects 

 will be caught in their attempts to creep up the trunks. In the 

 same way, also, those that are coming down the trunks to go into 



