Once symptoms manifest on the Serviceberry, treatments will not be effective for that year. Sometimes wet weather interrupts spray intervals, given the fungus the opportunity to infect, while also promoting conditions for infection itself, since prolonged leaf wetness tends to be conducive to spore infection for many plant diseases. Preventative fungicide sprays might be somewhat effective if applied regularly and early enough in spring to prevent the windblown rust spores emanating from junipers from infecting Serviceberry foliage, but they are not foolproof. Fortunately, the disease can be unsightly but rarely serious in threatening the host's long-term health. Removing nearby junipers to break the life cycle is not practical (not only are they valued native evergreens, but they are so common and the spores can blow a mile or more on the wind anyway) and treatment of the Serviceberry or other rose-relative hosts is not curative.
Our Rust Diseases of Trees web page doesn't list much for management options because there's not a lot that can be done.
DOWNY SERVICEBERRY PLUS
This gives these diseases their names, such as Cedar-Apple rust. A great series of images of the fungal spore structures plus symptoms of infection are in the page linked above. Rust fungi are a bit unusual in that they require two different host plants to complete their life cycle, in this case one in the rose family and the other being our native juniper, Eastern Redcedar. We agree that this appears to be the early-stage symptoms of rust, a very common and widespread native fungus that can infect Serviceberry as well as certain other tree/shrub members of the rose family like Crabapple, Hawthorn, Apple, etc.
0 kommentar(er)
