DO NOT INCREASE PLANT SUSCEPTIBILITY TO PROBLEMS THROUGH NEGLECT OR IMPROPER CARE. Additional information is in Extension bulletin E-1936, "Selecting Ornamental Plants" and
List of files and visuals associated with this text.
Extension bulletin E-1947, "Planting and Care of Ornamental Landscape Plants."
All plants can be affected by environmental and cultural problems. Only those occurring most frequently are listed here. Use pesticides only after an accurate diagnosis and control recommendation have been made. Use pesticides strictly in accordance with label directions. Always wear protective clothing and do not spray on windy days.
This list is for educational purposes only. Inclusion does not imply endorsement and omission does not imply discrimination. Not all of these pesticides are labeled or recommended in all states.
Hawthorn (Crataegus) Disease Problems Cedar-apple rust, leaf and twig rust control - chlorothalonil, triadimefon, thiophanate-methyl Fire blight no chemical control Leaf blight control - chlorothalonil Leaf spot, fungal control - copper, benomyl, chlorothalonil Powdery mildew control - benomyl, lime-sulfur, thiophanate-methyl, triadimefon Scab no chemical control
Insect Problems Aphids control - diazinon, acephate, insecticidal soap
Caterpillars control - diazinon, carbaryl, malathion, pyrethrum, Bacillus thuringiensis Fall webworms control - diazinon, carbaryl, Bacillus thuringiensis, pyrethrum Lace bugs control - diazinon, acephate, malathion, pyrethrum,
Scales control - adults: superior oil
crawlers: diazinon, carbaryl, pyrethrum, acephate, malathion, superior oil,
Spider mites control - malathion, superior oil, insecticidal soap Tent caterpillars control - diazinon, carbaryl, Bacillus thuringiensis, pyrethrum
Visuals associated with this text.
| Visual title - Visual size | Visual title - Visual size |
|---|---|
| Cedar hawthorn rust on hawthorn - 22K | Cedar hawthorn rust on hawthorn - 23K |
| Cedar hawthorn rust on hawthorn - 47K |


