HOW TO GROW AND MARKET FRUIT 



we have adopted the plan of describing briefly the enemies of 

 each fruit in the chapter given to the fruit, so they may be 

 recognized, and of telling the remedy for each trouble and how 

 to make and use it in the spraying directions and in the formulas 

 immediately following. Here we give general points that must 

 not be overlooked: 



Insects that chew are killed by poisons. Arsenate of lead is 

 used universally to control them, and is generally conceded to 

 be the only satisfactory remedy. 



Insects that feed by inserting their beak into the bark and 

 sucking juice cannot eat poisons placed on the surface, so they 

 must be gone after with a contact mixture that will kill them 

 when it touches their bodies. In the long search for suitable 

 materials for this purpose, experimenters had great trouble to 

 get mixtures of a chemical composition that would kill insects and 

 yet not destroy or injure trees. The margin is narrow and the 

 greatest care must be used in preparing the remedies, both to 

 get the right proportions of the different materials, and to com- 

 bine them right. A little change in mixing lime-sulphur, for 

 instance, may make all the difference between a solution that 

 is effective and one that is worthless or dangerous. 



To control sucking insects, the miscible oils may be used to 

 a considerable extent. Their chief value lies in their ability to 

 clean up quickly bad infestations of scale on apple and pear 

 trees. (They are also useful on shade trees, for several enemies.) 

 But nine-tenths of the time, lime-sulphur solution is unques- 

 tionably the best material for all sucking insects on all fruit 

 trees. 



Carefully note that some spraying is done on trees when 

 dormant with one kind of lime-sulphur; and when in leaf, with 

 a different mixture, or at a different strength. The scale insects 

 (or any sucking insects) are very hardy and difficult to kill. 

 Strong solutions must be used to do it, and these solutions would 

 kill foliage and tender twigs if applied during the growing 

 period. A solution that will not damage the foliage will hold 

 the insects in check. The solutions must reach every fraction 

 of an inch of surface and should go on with good pressure. 

 A pressure of 100 to 150 pounds to the square inch will insure 

 results that cannot be obtained with lower pressure, and will 

 economize material. 



Fungi and parasites are the third class of tree enemies 

 mentioned. These really are plants, of a very low order, which 

 live by attaching themselves to other plants and drawing their 

 food from the living bark, wood, leaves or fruit. Leaf spots 

 and rusts, the rots, etc., are familiar forms of fungi. Toadstools 

 and common mold are also fungi, of a different kind, growing 

 only on dead matter, while the fungi which bother trees grow 

 on living matter. 



Fungi generally increase by dividing their bodies and by grow- 

 ing a fruiting stalk, which finds its way up or out from the root, 

 as a plant stalk grows from the seed, then produces a spore 

 or spores. The spores are thrown off and scattered by wind, 

 birds, etc., and sometimes by fogs. Most fungi live inside the 



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