The few cases of injury are often reminders of the necessity for accurate, uniform 

 applications, advance planning, and well -reasoned judgment. 



Lasso and Lasso -plus -atrazine received new clearance for postemergence use in corn, 

 but that is for very small weeds and most fields are too far along now. 



NUTSEDGE 



Nut sedge is prevalent in many areas this season. Atrazine and oil postemergence may 

 help reduce the growth a little, but we really don't have very good answers for post- 

 emergence control of nutsedge in corn or soybeans. 



Plan next year to plant soybeans in areas badly infested with nutsedge. As soon as the 

 nutsedge starts growing, till the field once a week for two or three weeks to reduce 

 the food reserve of the nutsedge tubers. At the time of the last tillage operation, 

 incorporate Lasso or Vernam. Put this on your calendar for December 31. When you put 

 up your 1973 calendar, transfer the note to the first week of May. 



CORN ROOTING 



Dry surface soil may sometimes delay the downward growth of the crown roots of corn. 

 Because of the delayed establishment of the roots, plants may start leaning. Some dif- • 

 ferences in rooting ability of various hybrids has been noted. Usually cultivation to 

 throw moist soil around the crown will help correct the situation. 



PLANT DISEASES 



REPORT ON PLANT DISEASES (RPD SERIES) 



For a current listing of the Report on Plant Diseases (RPD) series, write to the De- 

 partment of Plant Pathology, 218 Mumford Hall, University of Illinois, Urbana 61801. 

 The RPDs are grouped by crop type, for example, cereals, corn and sorghum, and vege- 

 tables and canning crops. We try to revise these with each new development. 



A new RPD on Physoderma Brown Spot of Corn and four new RPDs on Turf and Lawn Dis- 

 eases are now "in the mill." Request the Index for Reports on Plant Diseases. 



POWDERY MILDEW ON WHEAT 



Erysiphe gvaminis tvitici, the fungus that causes powdery mildew of wheat, is now pro- 

 ducing black-colored fruiting bodies (perithecia) that enable it to overwinter on living 

 leaves of wheat in the field. The perithecia are imbedded in the mycelial mat found on 

 the surface of infected plant leaves, stems, and heads. The mycelial mat will probably 

 have changed from white to dark grey in color. Hot, dry weather has kept powdery mil- 

 dew in check. Crop rotation tends to reduce chances for severe infection. See RPD 104, 

 "Powdery Mildew of Wheat and Barley," for further details. 



LEAF RUST AND STEM RUST OF WHEAT 



Leaf rust, caused by Puacinia reoondita tritici, causes yield loss by reducing the num- 

 ber of kernels per head as well as the size of the kernels. Grain from severely rusted 

 plants also has lower test weight and protein content. Farmers usually underestimate 

 losses because the disease never destroys an entire Illinois crop and seldom causes se- 

 vere shriveling of the grain. 



