776 MANUAL OF POISONOUS PLANTS 



apparent to the naked eye. The lungs and kidneys apparently normal. The brain and spinal 

 cord were not examined. 



I am fully convinced that this disease is due either to some poisonous principle in the 

 plant or some parasitic fungus upon the surface of the same. It is now too late in the season 

 for any investigation to be carried on in this direction this year, but I intend to have the mat- 

 ter thoroughly investigated next summer. 



13. Aster (Tourn.) L. Aster 



Herbs generally perennial with corymbose panicled or racemose heads ; 

 heads many flowered, radiate ; the ray flowers in a single series, fertile. Bracts 

 of the involucre more or less irnbricated, generally with herbaceous tips; re- 

 ceptacles flat ; achenes somewhat flattened ; pappus simple, consisting of capillary 

 bristles. A large genus of 275 species, chiefly in eastern North America. 

 Flowering in the autumn. A few of the species are cultivated for ornamental 

 purposes. 



The New England aster (A. novae-angliae) occurs in moist ground. The 

 A. lacvis with somewhat clasping leaves is common in dry soil or prairie regions 

 of the West. The small white aster {A. midiiflorus) with small leaves is 

 common along roadsides in dry soil. Very few of the species have deleterious 

 properties. 



Aster Parryi Gray. Parry's Aster or Woody Aster. 



A somewhat hoary perennial with deep woody roots and a short more or 

 less branched stem ; hoary leaves, spatulate-linear, cuspidate ; heads solitary, 

 bracts of the involucre oblong-lanceolate, long acuminate, pubescent, rays white 

 over half inch long, achenes white villous. This is the Xylorhiza Parryi Gray. 



Distribution. Common in saline soils. In Colorado, West Wvoming and 

 Utah. 



Poisonous properties. This plant has recently come into prominence in 

 western Wyoming where the disease "grub in the head" has been attributed to 

 the plant but Dr. Aven Nelson ^ has attributed this disease to a fungus Puccinia 

 xylorrhisae which according to Dr. Nelson abundantly occurs on the plant. 

 He says : 



If it should prove to be true that the malady is due to the eating of the aster, then it may 

 be the aster itself that is the source of the trouble, but the chances are rather better that the 

 specific poisonous qualities are due to the fungus. Some other parasitic fungi have been 

 proved poisonous and we may well, in the absence of evidence to the contrary, also suspect 

 this one. 



Dr. Nelson states that the trouble is not a new one and that similar out- 

 breaks have occurred in previous years, the disease recurring in the same 

 localities. The disease was prevalent near Medicine Bow and northward to 

 the Shirley Basin as well as Natrona county. The farmers in the vicinity where 

 this disease occurs speak of the area in which the plant occurs as the "poison 

 patch." Dr. O. L. Prien, Wyoming Agricultural Station, and Dr. Frederick 

 of the Utah Agricultural Station, are making a careful study of this disease. 

 To prevent the trouble, sheep should be kept, so far as possible, away from areas 

 in which this plant occurs. 



14. lirigeron L. Fleabane, Daisy 



Branching or scaposc herbs with entire or toothed leaves; heads in corym- 

 bose, paniculate or solitary peduncled heads ; scales of the involucre narrow, 

 nearly equal, not foliaceous or green-tipped; flowers radiate, white violet or 

 purple, numerous, fertile; disk flowers j'ellow, tubular and perfect; branches of 



1 Press Bull. Wyoming Agr. Exp. Sta. No. 10. 



