EXPERIMENT STATION BULLETINS. 213 



24. February, 1904, Insects Injurious to Fruits, R. H Pettit. 



25. March, 1904, Fungous Diseases of Fruit, B. O. Longyear. 



26. April, 1904, Spraying Calendar, L. R Taft. 



27. May, 1904, Repoft of South Haven Sub-station, T. A. Farrand. • 



28. May, 1904, Report of Upper Peninsula Sub-station, L. M. Geismar. 



29. May, 19u4, The Associative Action of Bacteria in Milk, C. E. Marshall. 



Of this list, numbers 1. 3, 6, 12 and 19 are out of print. As long as the supply 

 lasts, copies of these special bulletins, not out of print, will be sent free to those 

 who apply for them. Hereafter the number and title of each special bulletin will 

 be given in the first regular bulletin issued after its publication. This bulletin 

 calls attention to special bulletins No. 24, No. 25 and No. 26. All three relate to 

 the enemies of fruit trees in Michigan and suggest remedies. The special bulletins 

 themselves should be in the hands of all farmers owning orchards or other fruit 

 plantations, as it is impossible in the limits of this bulletin to fitly review them or 

 to do more than name some of the most conspicuous diseases and remedies. 



THE APPLE. 



No fungous disease is reported as doing serious injury to the roots of this tree. 

 The woolly aphis attacks the roots and is treated by a liberal use of tobacco dust 

 or wood ashes, and it is good practice to dip young stock in water at 130° F., 

 kerosene emulsion or tobacco water, before setting out. 



The bark of the tree is attacked by the oyster-shell bark-louse, the eccentric 

 scale, the San Jose scale, and the scurfy bark-louse. Various remedies are sug- 

 gested for these several insect pests in special bulletin No. 24. Professor Pettit 

 does not deem the presence of even the San Jose scale, widely distributed as it is 

 over the State, as a menace sufficiently grave .to discourage the progressive fruit 

 grower. Fortunately for him the peril is sufficiently ominous to discourage the 

 half-hearted and incompetent orchardist and to leave the business of apple growing 

 in Michigan in the hands of men of sufficient energy and intelligence to guard their 

 orchards against these pests even at the expense of the frequent sprayings and the 

 bothersome methods which their unwelcome presence makes necessary. 



Two borers affect the trunk of the apple and the pear tree, and one of them at 

 least the peach. Professor Pettit suggests eternal vigilance as the price of the 

 early discovery of the depredations of these Insects, and the use of a stiff pin, a 

 knife and a wash of strong soap and salsoda, as the best cures. 



When we come to the branches of the tree the number of enemies increases.. 

 Here we have to deal with the apple scab, canker, black rot,, twig blight, fire blight, 

 buffalo tree-hopper and the apple twig-borer. The bulletins under discussion give 

 the latest discoveries concerning these diseases and the best remedies as yet sug- 

 gested The relation between the rots of the fruit and those peculiar scars upon 

 the bai"k of the limbs and even of the trunk that used to be called "sun scald" is 

 pointed out and its significance made clear. In the same way the relation of the 

 apple scab to diseases of the leaves and bark, and the importance of ridding the 

 orchard in late fall of diseased fruit, still clinging to the twigs, and of the dead 

 leaves upon the ground, is pointed out. One advantage supposed to be on the side 

 of cover crops as against bare ground was that the former would collect and hold 

 the leaves as well as the snaw and thus add manure to the soil as well as provide 

 a covering for the roots. Recent discoveries have shown that the leaves provide 

 a home for certain diseases through the winter, a resting place from which they 

 may issue the following spring to attack the tender leaves, the twigs and even the 

 fruit itself. 



The leaves of the apple tree are the most tender and succulent part of its 

 anatomy. These two bulletins point out three fungous diseases and name sixteen 

 species of insects that feed upon them. Fortunately the remedies suggested for 

 fighting these diseases are not great in number nor difficult to manufacture and 

 apply. The insects, for the most part, are poisoned by sprays of paris green, com- 

 bined with Bordeaux mixture, applied to ward off the fungi. 



The fruit is attacked by at least six different species of fungi. Some of them 

 utterly destroy, as the bitter rot and the ripe rot. Others disfigure, as the apple 

 scab, which opens the road for the rots. All of them are avoided by early, frequent 

 and judicious spraying. 



Three species of insects attack the fruit, but their depredations are very largely 

 avoided by spraying.s with Paris green. 



