EXPERIMENT STATION BULLETINS. 321 



likely to destroy all the curculio that appeared during the period of bloom. 

 In case rains wash off the poison, it should be reapplied. 



CURRANT WORMS. 



The usual remedy for the larvae that feed on the leaves of currants, is 

 hellebore, applied either dry or in water, but, as frequent applications are 

 necessary, we have come to rely on the arsenites. If applied in a thorough 

 manner, as soon as the eggs of the first brood begin to hatch, no other 

 treatment will be necessary, and, as the fruit is at that time very small, no 

 danger of poisoning it need be feared. For applications later in the season, 

 if they become necessary, hellebore in water, at the rate of a teaspoonful 

 to the gallon, will be safer, although a weak mixture of Paris green applied 

 in a fine spray would do no harm. 



COLORADO POTATO BEETLE. 



The arsenites have come so commonly into use, for the destruction of 

 this insect, that the only mention necessary here is to say that, when 

 thoroughly mixed, the amount required of the Paris green is much less 

 than is commonly used. When applied with plaster, one part to one hun- 

 dred, or even one part to two hundred parts of plaster, will answer very well, 

 if the mixing is thoroughly done. When one has a knapsack pump, 

 application in water, covering two rows at a time, will be fully as 

 satisfactory. 



CHERRY AND PEAR SLUG. 



This slimy, brown slug eats the soft part from the leaves of cherry and 

 pear trees, appearing during the early summer. Their advent should be 

 watched for, and remedies should be immediately applied. Dry dust, coal 

 or wood ashes, plaster or air-slaked lime thrown over the trees, will destroy 

 them, but, if the trees are large and numerous, the arsenites can be more 

 readily applied, and are rather more effectual. 



The above are among the insects that are most troublesome, and the 

 arsenites can be relied on to destroy them, and they will at the same time 

 kill such other insects as may be eating the foliage of the trees, or plants 

 to which they are applied. 



FUNGICIDES. 



Nearly all of our plants have from one to a dozen parasitic fungi, that 

 feed on their substance, and, if they do not destroy the plants themselves, 

 greatly lessen the value of the crops produced by them. 



The fungi themselves are plants of a very low order, and develop 

 rapidly from spores (seeds), when exposed to proper conditions of heat 

 and moisture. In some cases, they penetrate the substance of the plant 

 and destroy its cell structure; after a while, when they have finished their 

 growth, they burst out through the epidermis, and develop a mass of 

 slender stalks, on which the spores are produced. These, as a rule, are 

 minute spherical or elliptical bodies, generally colorless, orange, or black 

 and may at once germinate, giving rise to a new fungus, or may survive 

 until the following spring. 



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