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HOMEOWNER PROBLEMS 



Aphids are numerous on maple trees in some areas, causing the leaves to curl. Sprays 

 containing either malathion or diazinon will provide control. 



Mimosa webworms continue to be more numerous on honey locust and mimosa trees. The 

 caterpillars feed on the tips of the branches, causing the leaves to become ragged 

 and to turn brown. Also, these worms spin webs around the infested foliage. Apply 

 a spray of carbaryl, malathion, or Bacillus tkuringiensis (Biotrol, Dipel, or Thuri- 

 cide) . 



WEEDS 



NOT ALL ONION-LEAFING IS CAUSED BY HERBICIDES 



Don't be too quick to blame all "onion- leafing" (sometimes called "buggy whipping") 

 that you see in corn on injury from herbicides such as 2,4-D or Banvel (dicamba) . 

 Some corn hybrids and types show a genetically controlled onion- leafing that is not 

 associated with herbicide injury. 



To determine the cause of onion- leafing, try to find an area in the corn field that 

 has not been sprayed and check for frequency of onion- leaf ing there. If there is 

 less onion- leafing in the untreated spot than elsewhere, the condition is probably 

 caused by herbicide injury. If there is as much onion-leafing in the untreated spot 

 as in the rest of the field, the condition may be genetically controlled. 



There is no treatment for onion- leafing, but tassels will usually break through the 

 rolled leaves. The ears on onion- leafed plants can also be pollinated from nearby 

 corn plants . 



BETTER ALTERNATIVES TO SODIUM ARSENITE AS A ROADSIDE SPRAY 



We have received several calls concerning the use of sodium arsenite as a roadside 

 herbicide spray. This compound is our most toxic herbicide, with an acute oral LD50 

 of 10 to 50 milligrams per kilogram of body weight. Sodium arsenite has caused seven 

 deaths in Illinois during the past ten years--the only human deaths attributed to 

 herbicides during that period. 



Several years ago, sodium arsenite was restricted for homeowner use to compounds 

 with a 2-percent concentration or less. Under the proposed pesticide classifica- 

 tion system, sodium arsenite will be restricted for all uses in Illinois. 



In an attempt to "clear their shelves" before the new restrictions take effect, some 

 chemical companies have been selling sodium arsenite to county road commissioners. 

 These companies are suggesting the use of sodium arsenite as a roadside spray to re- 

 place 2,4,5-T (now restricted for use along waterways). So far this summer, two 

 cases of cattle poisoning from this herbicide have been reported. 



We have tried to discourage use of sodium arsenite because of its toxicity and be- 

 cause better methods of control are available. Sodium arsenite is an old herbicide, 

 one used in the past to control water weeds and to keep gravel paths and baseball 

 fields clean. 



We suggest using 2,4-D, silvex (fenoprop) , dichloroprop (2,4-DP) , or Ammate-X (AMS) 

 to control brush in areas where 2,4,5-T cannot be used, such as along drainage 

 ditches and other waterways . We would caution operators, however, about the drift 



