1890 ARBORETUM AND FRUTICETUM. PART III. 



We are not aware of there being any trees of this oak in the neighbourhood 

 of London; but we believe there are plants of it in the Edinburgh Botanic 

 Garden, raised from acorns brought over by Mr. M'Nab, jun., in 1834. (See 

 p. 182.) 



vi. Nigra. Black American Oaks. 



Sect. Char., $c. Leaves wedge-shaped, or imperfectly lobed ; mucronated, but 

 the mucros generally dropping off when the leaves have attained their full 

 size. Leaves dying off of a blackish green, and in America frequently per- 

 sistent. Bark black, and not scaling off. Fructification biennial. Nut 

 ovate, with a persistent style, and sometimes marked with dark lines. Trees, 

 from 20 ft. to 40 ft. high ; and one of them, a miniature tree, often not 

 exceeding 3 ft. in height. Rate of growth less rapid than in the preceding 

 sections. 



21. Q. NI'GRA L. The Black Jack Oak. 



Identification. Cat. Carol., 1. 19. ; Lin. Sp. PL, 1413. ; Willd. Sp. PL, 4. p. 442. ; Ait. Hort. Kew., 

 5. p. 291. ; Pursh FL Amer. Sept., 2. p. 629. ; Sm. and Abb. Ins., 2. p. 115. ; Michx. Quer., No. 12. ; 

 N. Du Ham., 7. p. 168. ; Sm. in Rees's Cycl., No. 53. 



Synonymes. Q. marylandica, &c., Raii\ . ferruginea Mich*. N. Amer. Syl. t 1. p. 79. t. 20. ; Q. 

 aquatica Lodd. Cat., ed. 1836; Barrens Oak, Amer. 



Engravings. Abb. Ins., t. 58. ; Michx. Quer., t. 22, 23. ; Cat. Carol., t. 19. ; and our fig. 1764. 



Spec. Char., $c. Leaves wedge-shaped, somewhat heart-shaped at the base ; 

 dilated, abrupt, and very slightly 3-lobed at the end; the middle lobe shortest, 

 smooth above, rusty beneath. Calyx hemispherical, with membranous 

 scales. Nut roundish-ovate. ( Willd.) A tree, 20 ft. or 30 ft. high. Intro- 

 duced before 1739. 



Description, $c. The Black Jack oak, according to the younger Michaux, 

 is sometimes 30ft. high, and Sin. or 10 in. in diameter, but commonly does not 

 exceed half these dimensions. Its trunk is generally crooked ; and it is co- 

 vered with a very hard, thick, and deeply 

 furrowed baik, which is black on the 

 outside, though the inner bark is of a 

 dull red. The head of the tree is broad 

 and spreading, even in the midst of the 

 woods. The leaves are of a very re- 

 markable shape, being dilated towards 

 the summit, like a pear, and armed, 

 when young, with 3 or 5 bristle-like 

 points, which fall off when the leaf has 

 attained its full size. Fig. 1765., from 

 Michaux's Histoire des Chenes, shows 

 these mucros on seedlings of one year's 

 and two years' growth. The leaves are 

 yellowish, and somewhat downy, at their 

 first unfolding in spring ; but, when fully 



expanded, they become of a dark green ff ^ 1 764 



above, and rusty beneath : they are also 

 thick and leathery in their texture. In autumn, they turn of a blackish red, 

 and fall with the first frost. The oldest trees bear only a few handfuls of 

 acorns, which are large, and half-covered with very scaly cups. Michaux 

 observed this species for the first time in some forests in New Jersey, about 

 60 miles east of Philadelphia. It is commonly found upon soils composed 

 of red argillaceous sand, mingled with gravel, and so meagre as scarcely 

 to bear cropping. The greater part of Maryland and Virginia, from Balti- 

 more to the borders of North Carolina (a distance of 400 or 500 miles), is, 

 according to the younger Michaux, composed of this kind of soil ; and here the 

 Black Jack oak is found in the greatest abundance. The whole of this in- 

 terval, with the exception of the valleys and the swamps, with their surround- 

 ing acclivities, is covered with forests impoverished by fire, and by the cattle 



