A SECOND OHIO WEED MANUAL. 



519 



Seeds lenticular, round, 1-20 inch in diameter, dull black, ripening- from 

 August to November. Frequently found in clover and alfalfa seed. To destroy 

 lamb's-quarters it must be prevented from seeding- by cultivation and destruc- 

 tion of all plants. This may be taken as a type of a number of weeds which 

 come in potato fields, corn and other crops receiving only early cultivation. 

 The remedy lies in more thorough destruction of them through better and 

 especially, through later cultivation. 



88 Wormseed (A) * Chcnopodium anthelminticum L. This is another 

 annual differing slightly from the preceding in the inflorescence and in having 

 a penetrating (to some, offensive) aromatic odor. It is more frequent in the 

 southern part of the state, but has been introduced generally. Seeds very 

 small, of the size of timothy seed, kidney shaped, light brown, small and 



shining. Not yet occurring very generally in commercial seeds. 



89 Mexican Tea (A) *Chenopodium ambrosioides L. Mexican tea is from 

 tropical America and differs from the preceding but slightly in the wavy 

 margins of the leaves and in minor characters. The seeds are small like those 

 of the next sort. 



90 Jerusalem Oak, Feather=geranium (A) * Chencpoditim Botrys L. 

 Jerusalem oak strongly resembles the preceding, but differs from it in being 

 smaller, having leaves deeply lobed and dull seeds; also occurs in waste places. 



91 Nettle =leaved Goosefoot (A) * Chenopodium murale L. This is suffi- 

 ciently designated by the name and having the lamb's-quarters in hand or mind. 

 It is distributed less widely in Ohio than some others but may become an omni- 

 present weed of like character with those better known. 



92 Oak=leaved Goosefoot *Cheopodium glaucum L. Naturalized from 

 Europe, is becoming frequent in waste places and especially along railways. 



93 Maple=leaved Goosefoot (A) Chenopodium hybridum L. This plant 

 has one to four large, pointed lobes to the leaves, which gives the resemblance 

 and name. While a native plant, it may spread as a weed in waste places. 



94 Orache Atriplex (A) * Atriplex 

 hastata L. This plant, Fig. 18, allied to 

 to the garden orache, has recently been 

 introduced and now ranks with lamb's- 

 quarters and pigweed in its pestiferous 

 characters. It occurs especially along 

 railway embankments and on vacant lots 

 in cities. It is very spreading in growth, 

 forming a broad mass one to two feet 

 high and several feet in diameter. It is 

 attacked by the mildew, Peionospora ejfu- 

 sa, which injures spinach and orache. 



Seeds resembling those of lamb's- 

 quarters. Fig. 18a, nat. size; b,x6. 



This weed should be uprooted before 

 the seeds begin to form. Mere cutting 

 with the scythe is not sufficient, because 

 the plant stools freely and the stems are 

 too low to be reached in this manner. 



95 The lance-leaved, Atriplex potato, 



L., with this marked difference from the 



figure, also occurs as an Ohio weed. 



96 Silvery Orache (A) *Ateiplex argentea IX utt. This is a native of the 



western United States and is reported by Dr. Kellerman as present in this 



state. The plant is densely silvery-scurfy with foliage otherwise much as the rest 



of the genus. Less likely than the commoner sorts to be troublesome as a weed. 



Fig. 18. Atriplex. 



