CARTER: ILLINOIS TREES: THEIR DISEASES 27 



keep them running while slowly sifting in 8 pounds of copper 

 sulfate and then 8 pounds of lime. Finish filling the tank with 

 water. Use the spray mixture immediately. A sticker, such as 

 soybean flour, 4 ounces to 100 gallons of spray, will Increase the 

 effectiveness of Bordeaux and other copper sprays. 



Copper compounds sold under various trade names may be 

 substituted for Bordeaux mixture. 



Cycloheximide. — An antibiotic fungicide sold under such 

 trade names as Acti-dioui' and Actispmij. It kills the spore-horns 

 on the galls of the cedar-apple and cedar-hawthorn rusts and it 

 controls leaf blight of hawthorn. 



DDT. — A chlorinated hydrocarbon insecticide. Formulations 

 of DDT are sometimes recommended for the control of the insect 

 vectors of phloem necrosis and Dutch elm disease. Several con- 

 centrates of these formulations are on the market. Application 

 of foliar DDT sprays over a period of years may bring about 

 population increases of harmful insects and mites. Other chem- 

 icals may be needed to control these pests. DDT is hazardous to 

 birds and other wildlife. In its use, special care should be ex- 

 ercised to hold bird losses to a minimum. Feeding stations, water- 

 ing places, and other places frequented by birds should be pro- 

 tected from spray drift and run-off. Bird baths should be cleaned 

 following spraying. Collection of spray in puddles, likely to occur 

 when hydraulic sprayers are used, should be eliminated. In spite 

 of these precautions, it is probable that birds will be killed, 

 especially robins early in the season. Spraying should be under- 

 taken with the prior knowledge that such losses may occur. 

 Methoxychlor is much less hazardous to birds and other warm- 

 blooded animals and it can be substituted for DDT. Although a 

 methoxychlor spray costs two to three times as much as a DDT 

 spray for material, the cost of labor in applying each spray is 

 the same. 



Dichlone. — A fungicide sold under the trade name Phygon 

 XL. It controls black leaf spot of elm when it is used under 

 Illinois conditions. 



Dodine. — A fungicide recommended for the control of scab 

 of crab apple, hawthorn, and mountain ash and leaf blight of 

 hawthorn. It is sold under the trade name Cyprex. 



Ferbam. — A fungicide sold under such trade names as 

 Fermate, Karham Black, and Niagara Carbamate. It is used for 

 the control of rusts on juniper, hawthorn, and crab apple and for 

 the control of powdery mildew. 



