Corn samples collected from cribs in ten widely scattered counties in Illinois 

 show that the SCLB fungus is alive and highly virulent in dry corn. This should 

 be our main source of local infection during 1971. So we suggest that farmers 

 shell-out blighted com in their crib before they plant this year's crop. 



Planter-box treatment . The emergence and stand of infected T and B seed corn 

 can be increased by about 10 percent with a planter-box treatment of captan, 

 thiram, or maneb seed protectant. Use 1 to 2 ounces of actual fungicide- -2 to 

 4 ounces of formulated material- -per bushel of seed. We suggest mixing the fun- 

 gicide with the seed in the planter box. Some of the dust will fall around the 

 seed when it drops and will help prevent preemergence damping-off . 



DuPont has a thiram seed protectant (arasan 50-Red) , formulated for use in the 

 planter box. The Hopkins Agricultural Chemical Company of Madison, Wisconsin, 

 has formulated a thiram-maneb treatment. Both the Arasan and the thiram-maneb 

 treatments contain graphite to help prevent plugging or planter "drag." 



TREATING OAT SEED 



Since the "hard" mercuries were banned a year ago, many farmers have asked what 

 they should use for treating oats and wheat in 1971. There are several possi- 

 bilities . 



1. You can still apply any leftover ceresan, panogen, ortho L M, or chipcote. 

 The ban means that these products cannot be shipped across state lines any- 

 more and that their manufacture has been largely discontinued. 



2. The next best bet would probably be products that contain phenyl mercuric 

 acetate (PMA) . This is a liquid (0.078 ounce per bushel), formulated for 

 use in Mist-O-Matic and similar treaters. It is "soft" mercury that does 

 not accumulate in body tissue and has label clearance. Mercuries are the 

 only fungicides that are volatile and will kill-out fungus spores under the 

 seed coat. 



3. Other possible seed treatments include captan- -2 ounces per 100 pounds, ap- 

 plied dry, or 2.8 ounces per 100 pounds as a slurry- -and Chloranil (Spergon) , 

 applied dry, using 6 ounces per 100 pounds. 



4. There are additional products that have label clearance, but they are either 

 hard to get or difficult to handle. These include formaldehyde- -1 pint per 

 40 gallons of water or 1 pound of dust per 15 gallons of water; hexachloro- 

 benzene (HCB)--0.2 ounce of actual chemical per bushel, applied dry or as a 

 slurry mix; maneb- -1 ounce of actual chemical per bushel; raformaldehyde-- 



3 ounces per bushel; and zineb--0.5 ounce per bushel. 



Note: We have not had the opportunity to test these products on oats. 



READ THE INSECTICIDE LABEL AND FOLLOW ALL PRECAUTIONS 



This weekly report was prepared as follows : 



INSECTS: H.B. Petty, Steve Moore, Roscoe Randell, Don Kuhlman, and Tim Cooley , 

 College of Agriculture, University of Illinois at Urbana-Champaign , and the Il- 

 linois Natural History Survey. 



