213 



cutting of the mature trees accompanied by the establishment of a 

 young growth from the seed scattered by the seed trees which remain, 

 or by means of coppicing. Coppicing is a practical method of regen- 

 eration especially on rich, moist soils and where very large sizes 

 are not required. The artificial regeneration may be accomplished 

 by sowing seeds, or what is still better, by collecting the seeds, 

 planting them in the nursery, and after a year's growth in the nur- 

 sery, lifting them and planting them out upon the area where they 

 are to remain and produce a timber crop. 



The leaves of the Ashes are opposite and compound. The leaf- 

 lets occur in 2s opposite each other along the principal leaf-stalk 

 with a single leaflet at the end, hence the total number of leaflets is 

 always odd. The twigs are stout and occur in pairs opposite each 

 other along the main axis. The branchlets are usually flattened at 

 the nodes. The flowers are produced in dense clusters and usually 

 appear in spring before the leaves have made their appearance. The 

 fruit, known as a samara, matures in fall and occurs in clusters. 

 The individual seed is winged at one end. This wing aids in the dis- 

 persal of the seed by the wind, which is the most important disper- 

 sing agent ; but water may also scatter a large quantity of the seeds, 

 especially of such species which are commonest near streams or 

 where flood waters occur. 



The Ashes are distributed throughout the north temperate zone 

 and comprise about 40 known species, of which number 16 occur in 

 North America and 4 in Pennsylvania. Three species are common 

 in this State, while another species known as the Biltmore Ash 

 (Fraxinus Biltmoreana, Beadle), is found locally only over a limited 

 region in the southern part of the State. A variety of the Ked Ash 

 known as the Green Ash (Fraxinus pennsylvanica var. lanceolata) 

 is also found locally in the southern part of the State. 



SUMMER KEY TO THE SPECIES. 



Page. 

 1. Leaves with sessile leaflets; seed surrounded by wing; bark scaly, not furrowed with 



diamond-shaped fissures, F. nigra 215 



1. Leaves with stalked leaflets: seed partly surrounded by wing; bark furrowed with 



diamond-shaped fissures, 2 



2. Leaves and twigs smooth or nearly so; seed usually winged only at apex 



F, americana 214 

 2. Leaves and twigs velvety pubescent; seed winged usually at apex and sides, 



F. pennsylvanica 216 



WINTER KEY TO THE SPECIES. 



1. Buds usually black and acute at apex; bark scaly, not furrowed with diamond- 

 shaped fissures; tall and slender, F. nigra 215 



1. Buds rusty to dark brown, usually obtuse at apex; bark furrowed with diamond- 



shaped fissures; tall but stout, 2 



2. Twigs smooth or nearly so; leaf -scars evidently indented on upper margin, .... 



F. amfericana 214 

 2. Twigs velvety pubescent; leaf -scars not evidently indented on upper surface, .... 



F. pennsylvanica 2U 



