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Fruits
Volume 58 Number 13 Date 08/01/2013 APPLE MAGGOT - Emergence and oviposition continued for the fifth week. Counts have been low since the first flies appeared in early July and ranged from 0-7 per trap this week, with the high count registered near Hillpoint in Richland County. Based on the apple maggot degree day model, peak emergence of the fly population should occur in the next two weeks in the southern half of the state. CEDAR-HAWTHORN RUST - This rust disease is reportedly affecting about 25% of the fruits on ornamental hawthorn in the DeForest area of Dane County. Cedar-hawthorn rust, as its name implies, requires both a rosaceous host such as hawthorn and a juniper host to complete its life cycle. Selecting resistant hawthorn cultivars and thorough sanitation (removing as much of the infected twigs, fruit and leaves as possible) are the recommended controls. Fungicide treatments applied as new growth appears and flower buds start to open may be justified for severe cases. SPOTTED TENTIFORM LEAFMINER - The second flight has peaked in southern and central apple orchards where 1,479-1,523 degree days (base 50°F) were surpassed as of August 1. The economic threshold for the third and final generation increases to five mines per leaf. FIRE BLIGHT - An apple grower in Chippewa County reports that fire blight has been severe this season and some orchards in the area have removed infected trees. -- Krista Hamilton, DATCP Entomologist 
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