MICROSCOPICAL EXAMINATION. 75. 



Lady's tliiiiul), smari \vred ( Pnliiiinnum /xrxiruriii L. >. 



Curled (lock seed i /{nun. r rr/'.s-yw* I,.). 



Sorrel (Hiunex acetosclla L.). 



Cow cockle, cow-herb ( Vaccaria vaccaria (L.) Britton; Faccan'a rulgaris Host; 

 Saponaria raccaria L.). 



Soapwort, Bouncing Bet (Saponaria ojjicinalis L.). 



Charlock, wild mustard, Dakota musiard ( Hrassira armm* (L.) H. S. I'.; nnuaAca 

 ipistrum Boiss; /Sinapis arvcnsis L.). ;'id other species. 

 Darnel, lares (Loliinn l< nitilcntum L.). 



Jimson weed, Jamestown weed, thorn apple ( Itahirn slrtiiiinniuin L.). 

 Pigweed (i'lnnniHnl!itin *p.). 

 Roiiijh pigweed (Amaranthm sp.). 



(Jn-en t'dxlail (Chat'tochloa mridis (L.) Scribn.; Setaria mridis Beauv.). 

 Yellow I'oxiail ( < 'hititoehloa glauca (L.) Scribn.; Setaria glauca licauv.)- 

 l'> rat ted plantain (Plant-ago aristata Michx.), erroneously called huckliorn. 

 Rib grass (P. lanceolata L. ). 

 Ru^el's plantain (P. rngelii Decaisne). 

 Chess (Browns secalinus L.). 

 Rose seed (Rosa sp.). 

 Pepper grass (Lepidium virginioum L.). 

 Hare's-ear (Conringia orientalis (L.) Dumort). 

 Ragweed (Ambrosia artemisixfolia L.). 

 Night-flowering catchfly (Silene noctijlora L.). 

 "Wild bcrgamot, horse mint ( Monarda fistulosa L.). 



The materials entering into stock foods are of such character that 

 the presence of weed seeds to a greater or less extent is almost univer- 

 sal in certain kinds for example, in oats. As every one is aware who 

 is familiar with this grain there is often present quite a large amount 

 of pigweed as well as other seeds. In preparing stock feed there is 

 commonly little or no attempt made to remove such foreign material 

 and so it will usually appear in the final product. In this report 

 there are mentioned' by name, as far as possible, all those cases where 

 weed seeds have been found, but in most cases such presence should 

 not cause the product to be condemned, since the microscopic method 

 will often detect and identify them when the quantity present would 

 not in the least affect the value of the product. In the case of poison- 

 ous seeds, however, the amount should of course be kept at a minimum, 

 for if present to any extent the product becomes positively injurious. 



As an illustration of this might be mentioned a case of the poison- 

 ing of poultry by corn cockle which recently came to the writer's 

 attention. Although this seed is rarely considered poisonous, yet 

 in sufficient amounts it is very harmful. Corn cockle a - is a frequent 

 weed contamination in wheat and is usually present in such small 

 amounts that no notice is taken of it, but in the case referred to a 

 large number of chickens had been killed. The owners attributed 

 the trouble to the wheat middlings which they were feeding. An 

 examination for metallic poisons was first made, but none was found. 

 A microscopic examination of the food, however, showed that there 



a Chesnut, U. S. Dept. Agr., Farmers' Bulletin No. 86. 



