EXPERIMENT STATION BULLETINS. 223 



and one of the greatest arguments for the use of a cover crop; to 

 assist in holding the leaves that will decay and be plowed under; to 

 hold the snow which may prevent injury to the roots, and to add humus 

 to the soil. On light, thin soils the supply of humus soon becomes 

 exhausted. It can be supplied by the applicatian of barn^^ard manure, 

 but it is cheaper and easier to supply it by the use of a cover crop. 



By using nitrogenous plants for the cover crop, nitrogen will be 

 added to the soil. These plants have the power of collecting nitrogen 

 from the air, storing it in the nodules on the roots, and when they are 

 plowed under and decay, this nitrogen becomes available as plant food. 

 Nitrogen is an expensive fertilizer to buy, and with a good cover crop, 

 there will be no need to secure a further supply. 



Spraying must be made a regular practice. The neglected trees have 

 probably sheltered insects and diseases for some years that must be 

 subdued by thorough and regular spraying, as is directed farther on. 



These are general directions for improving an orchard that has not 

 been paying for itself. Good judgment must be used in all the opera- 

 tions. Do not carry any one operation to excess or to the neglect 

 of others. The trees are being stimulated along several lines as prun- 

 ing, cultivating, fertilizing and spraying, and each nvust be an accom- 

 paniment to the others. 



Success depends upon many things, but the first thing is the man. 

 To undertake this work in a half-hearted way will discourage success. 



THE SPRAYING OF APPLK ORCHARDS. 



Michigan apple orchards cannot be relied upon to bring forth crops 

 of clean, sound apples in pajing quantities unless thoroughly sprayed. 

 Apples must be of good size, attractive in appearance and sound, free 

 from worms and blemishes, so that they will keep in storage for their 

 normal length of time ; and unless the trees, fruit and foliage are 

 insured against the attacks of insects and fungous troubles that are 

 apt to come at any time, such fruit cannot be expected to mature. 



Fruit and foliage are kept free from these troubles by a very thin 

 film of spraying mixture, the spore, which is the seed of the disease, 

 being unable to grow through this substance; hence, the great im- 

 portance of having the material upon the foliage and fruit before the 

 disease starts. 



Insects are destroyed by eating parts of plants upon which has 

 been sprayed a little poison, or by having their bodies struck by some 

 penetrating substance, such as oil. 



The standard material to insure protection against fungous troubles 

 is called Bordeaux mixture; the name "Bordeaux" was taken from the 

 place in Prance where the mixture originated. It could just as well 

 be called '^Detroit," "Jackson," or "Charlevoix." There are but three 

 things used in its preparation, water, lime and copper sulphate. The 

 water acts as a carrier, the lime neutralizes the caustic action of the 

 copper sulphate and also makes the mixture stick to whatever it is 

 sprayed upon, and the co])per sulphate is the chemical that prevents 

 the growth of the spore of the disease. 



These three substances are combined in various proportions, depend- 

 ing upon the kind of plant to be treated ; but for apples, the one gen- 



