WEEDS OF THE POTATO FAMILY. 



125 



at base, closed at tip and loosely surrounding the green or yellow berry. 

 Seeds numerous, kidney-shaped, flattened, with a thin edge, finely pitted. 

 (Fig. 88.) 



Very common in lowland sandy fields and waste places. June>- 

 Oct. This is the most abundant of the 8 species of ground cherries 

 listed from the State. All can be recognized by the much inflated 

 bladdery calyx which encloses the small tomato-like fruit. They 



are distinguished one from another by 

 the smoothness or hairiness and shape 

 of the leaves, by the color and size of 

 the flowers and by the shape of the 

 calyx in fruit. The one above de- 

 scribed is the only common annual 

 form. Among the perennial ones with 

 underground rootstocks the clammy 

 ground-cherry (P. heterophylla 

 Nees.), having large heart-shaped 

 leaves, 2 inches or more long, densely 

 clothed with short more or less sticky 

 hairs; the Virginia ground-cherry 

 (P. virginiana Mill.), with ovate, 

 sparsely hairy leaves and fruiting 

 calyx cone-shaped, 5-angled and deeply sunken at the base, and the 

 prairie ground-cherry (P. lanceolata Michx.), leaves narrow, lance- 

 olate or spoon-shaped, fruiting calyx rounded, egg-shaped, scarcely 

 angled and little sunken at the base, are the common forms. Rem- 

 edies: thorough cultivation; mowing or cutting the perennial 

 forms two or three times each season. 



91. SOLANUM CABOLINENSE L. Horse Nettle. Bull Nettle. Sand Brier. 



Tread-soft (P. N. 1.) 



Erect, branched, *l-2 feet high, the branches, leaf-stalks and mid-ribs 

 of the leaves armed with numerous short, stout, awl-shaped yellow 

 prickles; leaves oblong or ovate, 2-6 inches long, cut-lobed or toothed, 

 covered with numerous minute star-shaped hairs. Flowers in loose clus- 

 ters ; calyx lobes tapering ; corolla wheel-shaped, purplish or white. Berry 

 naked, orange-yellow, about \ inch broad, closely resembling that of the 

 potato. Seeds numerous, straw-color, flat, rounded or ovate, 1/10 inch 

 long. (Figs. 10, d; 11, e, 89.) 



A very common and pernicious weed growing in both culti- 

 vated ground and pasture land, especially in dry and sandy soils. 

 May-Sept. It is a southern species which has spread widely both 

 by strong rootstocks and numerous seeds. In many places in the 

 southern two-thirds of Indiana it has, in recent years, become one 



Fig. 88. Fruit enclosed in calyx. (After 

 Britton and Brown.) 



