stem Belworm {TylencJms devaa- 

 tatrix) (apt an insect) 



INJURIOUSNESS OF WEEDS 677 



Charlock and other Cruclfers "I Diamond-Back Moth (Plutelfa mac- 



Prickly saltwort (.Salsola kali) j uUpennia) 



''ISo.lTn f^.£S ™^"^} ^^^-^ ^'^ '^'^^^ '^--^^« 



Hops, Yorkshire Fog, Poa annua, 

 Daisy, Shepherd's Purse, Spurrey, 

 Buttercup, Cornflower, Sow This- 

 tle, Black Bindweed (Polygonum 

 Convolvulus) and Plantain 



Nightshades Henbane. Hed^e, Mus-1 ^^^^^^^^ ^^^^^^ (Doryphora aecem- 

 tard. Thistles, Goosefoot, and t i^eata) 

 many other plants J ■"■>'""■"■/ 



Shepherd's Purse, Winter Cress, \ Cabbage Root Fly (Phoriia trot- 

 Hedge Mustard J sieae) 



Various Grasses }• Frit Fly (.Osdnis frit) 



Docks, Goosefoot, and some other 1„ .■,,,. ^. ..» 



y^gg^a r Bean Aphis {Aphis rumicis) 



\ Ghost or Otter Moth (Bepialus 

 Docks, Thistles, Burdock r lupuli) 



7. WEEDS ARE INJURIOUS BECAUSE THEY HARBOR PARA- 

 SITIC FUNGI. 



Long and Percival, in ''Common Weeds of the Farm and Gar- 

 den," have the following table of fungus diseases that affect var 

 rious weeds : 



Weed "host." Disease. 



1 Finger-and-toe of turnips {Plasmodia- 

 Charlock and other Crucifers I phora irassicae Wor.) 



J Peronospora parasitica De Bary 



(White Root-rot (Rosellinia necatrix 

 Prill.) 

 Sclerotium Disease {Sclerotinia scleroti- 

 orum Mass.) 



Wild Barley {Hordeum mur- "1 Blindness in Barley and Oats (Helmintho- 

 inum) J- sporium gramineum Erikss.) 



Shepherd's Purse and other"! White Rust of Cabbages (Oystopus can- 

 Crucifers j didus Lev.) 



Many species } ^^°^^^^ Root-rot (Rhigoetonda iHolacea 



Agrostis canina L., and other"! Reed-mace Fungus {Epichloe typhina 

 grasses j" Tul.) 



