94 SHADE TREES. 



which grows over the surface of, or penetrates, its host, 

 eventually coming to the surface to produce its fruiting 

 bodies or sporophores. These sporophores may vary in size 

 from the microscopic in some species to the very large 

 structures of other species which are usually known as mush- 

 rooms or toadstools. These familiar fruiting bodies on trees 

 may be from parasitic fungi which cause diseases, or they 

 may be from saprophytic fungi which follow diseases and 

 live on the dead and decaying material. In order to defi- 

 nitely determine this point it is necessary for the observer 

 to be familiar with the organisms. 



Some of these fungus diseases are very destructive to 



forest, shade and ornamental trees, and every effort should 



be made to eradicate or control them, but most 



Not all ... m , 



fungi of them are of minor importance. I he ma- 



jority of the large fungus growths are sapro- 

 phytic, and although not the cause of diseases they destroy 

 great quantities of timber which would otherwise be useful. 

 In this paper only the more common and conspicuous dis- 

 eases will be discussed, but some others which at the present 

 time are of minor importance in the State will be mentioned. 

 Any part of the plant, roots, stems, leaves, flowers and 

 fruits, are subject to the attack of diseases, but the disease 

 is not always manifest at the point of attack, 



diseases. i. c., a disease of the roots may frequently be 



detected by a dying of the leaves and branches. For con- 

 venience the diseases of trees may be arbitrarily grouped as 

 follows : 



1. Diseases of the foliage. 



2. Diseases of the stems. 



3. Diseases of the roots. 



4. Diseases due to environment. 



5. Other diseases. 



