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OTHER TREE DISEASES <br /> Tree diseases of shade and ornamental trees had an average <br /> year in Mounds View. Oak anthracnose was present but not 1111nearly as damaging as in previous years. Fireblight, apple <br /> scab/rust and verticillium wilt were not present in any great <br /> amount. <br /> Uncommon diseases seen in 1984 included cytospera on blue <br /> spruce ( dead and dying lower branches) and powdery mildew on <br /> flowering crabapple . <br /> Much of the severe winter damage was mistaken for tree disease <br /> in the case of mountain ash, white ash and Norway maple . <br /> DAMAGING TREE INSECTS <br /> Most populations of tree-damaging insects were down in 1984 . <br /> Cankerworm and linden looper activity in the spring was barely <br /> noticeable . The more common of the gall problems seemed less <br /> significant as well . Only long spruce cone gall showed any <br /> increase over previous years ( on Colorado blue spruce and <br /> Douglas fir) . <br /> Fall webworm was again present, but in no great numbers. It <br /> does, however , appear to be more widespread than in the past. <br /> Other insects prompting citizen concern were the imported wil- i <br /> low leaf beetle , rose chafer beetle , jackpine sawfly, ash <br /> plant bug and the birch leaf miner . <br /> GYPSY MOTH <br /> By far , the one greatest potential threat to all trees in <br /> Mounds View is the gypsy moth. This insect, an efficient <br /> defoliator in the larval stage , shows a preference to eating <br /> oak foliage , but will feed on any tree species including pine <br /> and spruce . <br /> For the second consecutive year , multiple catches of the adult <br /> male moth have turned up in State and Federal attractant traps <br /> in the Knollwood Drive/Woodale Drive area. A thorough foot <br /> search for egg masses in the area by five State/Federal crews <br /> yielded no results. Thus, the source of infection is still <br /> unknown . <br /> Egg masses were found in three other communities in the fall <br /> of 1984 . These will all be aerial sprayed in the spring of <br /> 1985. As no masses or other life stages of the moth were <br /> found in Mounds View, no spraying will be done here . <br /> Increased trapping will take place in 1985 with hopes of pin- <br /> pointing the infection source by fall . 4110 <br />