312 



DKSCIUITIOXS OF THE SHRUBS 



The species seen with chalky bark is generally the WHITE BIRCH Betula 

 alba of Europe, \vhirh grows to the lieight of 80 feet in its regular form. 

 '1 here are a score of named varieties some of which are low trees and some 

 only shrubs, as EUROPEAN WHITE BIRCH Betula pndula'(552). 



The four species always shrubby in growth are : SCKCB or DWARF BIRCH 

 (553) Betula glandulosa, 1 to 4 feet high with rounded small leaves, 

 i to 1 inch long, and brown glandular warty twigs; DWARF BIRCH (-354) 



- Betula nuna, a low spreading 

 smooth shrub rarely 4 feet high 

 with small rounded notched leaves 

 broader than long ; Low or SWAMP 



FIG. 554. Dwarf Birch. 



FIG. 555. Low Birch. 



BIRCH (555) Betula pumila, 2 to 15 feet high with longer and less 

 rounded leaves having dense brownish hairs below when young ; and 

 SHRUBBY BIRCH (556) Betula humilis, 2 to feet high, with glandular 

 twigs aaid crenately-serrate smooth leaves to 1| inches long. [Seeds.] 



Alnus. The ALDERS are generally shrubby plants growing abundantly 

 along streams and in damp places. They have alternate simple straight- 

 veined notched deciduous leaves and dry rounded cones which remain on 

 the bushes throughout the year ; these cones are the best test of the 

 alders. Most have catkin flowers opening in early spring. The species 

 with fall catkins is usually a tree to 30 feet. SKASII.K AI.I.K.K (557) Alnus 

 maritinia. which has shining foliage and yellow catkins in August to 

 September. 



