MANUAL OF PENNSYLVANIA TREES. 



IDENTIFICATION OP SPECIES. 



Names op Trees: 



Trees have two kinds of names, common and scientific. Some 

 species of trees have only one common name while others may have 

 as many as thirty. The same species of tree may have one common 

 name in one locality and an entirely different one in another locality. 

 The Pitch Pine described on page 71 is known in some parts of this 

 State as Jack Pine and in other parts as Nigger Pine. The common 

 name given at the top of each descriptive page is the proper common 

 name and the one used throughout this publication for that particular 

 species. Under the heading "Distinguishing Characteristics," other 

 common names are given. 



Since Linnaeus published his "Species Plantarum" in 1753, 

 plants have been known by scientific names. These names, as a rule, 

 consist of two parts, the generic and the specific, as is shown by the 

 following species of trees: — Pinus Strobus, Quercus alba, Fraxinus 

 americana, Acer rubrum. The first or generic part refers to the 

 genus and corresponds to a surname. The second or specific part re- 

 fers not to a group of plants but to a particular kind and corre- 

 sponds to the Christian name of a man. The White Pine, Red Pine, 

 and Pitch Pine are different kinds of pines. They belong to the 

 same genus or group and hence have the same generic name, Pinus. 

 Each one, however, is designated by a different specific name. For 

 example, the White Pine is known as Pinus Strobus, the Red Pine 

 as Pinus resinosa, and the Pitch Pine as Pinus rigida. Closely re- 

 lated species are placed in the same genus and closely related genera 

 (plural of genus) in the same family. Such closely related trees 

 as the Pines, 'Spruces, Firs, and Larches, are placed in the Pine 

 family — Pinaceae. 



At the time when plants first were studied seriously the Latin 

 language was the one used most commonly to preserve knowledge. 

 The plants consequently were given Latin names. The giving of 

 Latin names to plants and animals has continued down to the 

 present time and no doubt will continue. In the Latin language one 

 finds that plant-names have gender, and that the termination differs 



(55) 



