Symptoms 



grejdsli-brown hard resting bodies of the fungus 

 through cracks in the bark, especially in spriag. 

 PoLYANTHxrs. See Primrose. 

 Poplar. 



Various spot-forming fungi occur on poplar 

 leaves, e.g. Septoria Populi (small round whitish 

 spots with greyish margin edged with brown), 

 Marssonia Populi. 



Two rusts, Melampsora aecidioides and M. 

 populina, occur on poplar leaves, the former 

 forming yellowish groups of spores closely 

 scattered over the lower surface, the latter 

 brown ones or later blackish ones covered by 

 a crust, also on the lower surface. 



Blisters on leaves, convex above, concave and 

 golden yellow below, attacking also catkins of 

 poplar and aspen. Due to Taphrina aurea. 

 Potato. 



Tvber. — Brown discoloration just beneath 

 skin. Blight. Phytophthora infestans, see 

 foliage. 



Oval or round scurfy spots on skin. Brown 

 scab due to bacterium, Actinomyces chromo- 

 genus. Steep seed tubers in formaUn, 1 part 

 to 200 water, for 2 hrs. before sprouting. 



Deep scabs, dark green at first, generally 

 most numerous near " nose " end. Canker due 

 to Spongospora subterranea. Avoid planting on 

 same soil in next season. 

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