Crabapple tree problems - Ask Extension
Our once beautiful crabapple tree has a disease. It's about 12 years old and has always thrived. Last year there were some spots on the leaves, but th...
Knowledgebase
Crabapple tree problems #563043
Asked May 20, 2019, 6:52 PM EDT
Our once beautiful crabapple tree has a disease. It's about 12 years old and has always thrived. Last year there were some spots on the leaves, but this year half the leaves are curled and dead. Please see the pictures below, and let me know if there's anything we can do.
Thanks,
Carroll County Maryland
Expert Response
Crabapples can be susceptible to several fungal diseases. This looks like a rust disease on the foliage. Rust diseases have a complicated life cycle in that two types of plants, a pomaceous plant (apples, pears, serviceberry/shadbush, quince, and crabapples), and a cedar in which to complete their life cycle. This disease is unattractive but does not kill the tree. This can be common in moist spring weather. Rake and destroy any fallen leaves and fruit. Read more about it on our website. https://extension.umd.edu/hgic/topics/rust-diseases-trees
We do not recommend trying to control rusts on ornamentals with fungicides. In the landscape, damage to either host is not severe enough to warrant fungicide applications. Fungicides are preventatives and would not cure what is already there. They only protect new or uninfected foliage.
It is recommended to purchase the most disease resistant varieties in the future. See the attached links http://www.clemson.edu/extension/hgic/plants/landscape/trees/hgic1007.html
http://content.ces.ncsu.edu/superior-crabapple-trees-for-the-landscape
Marian
We do not recommend trying to control rusts on ornamentals with fungicides. In the landscape, damage to either host is not severe enough to warrant fungicide applications. Fungicides are preventatives and would not cure what is already there. They only protect new or uninfected foliage.
It is recommended to purchase the most disease resistant varieties in the future. See the attached links http://www.clemson.edu/extension/hgic/plants/landscape/trees/hgic1007.html
http://content.ces.ncsu.edu/superior-crabapple-trees-for-the-landscape
Marian
Marian,
Thank you for your response. Though the rust disease is not supposed to kill the tree, it certainly looks terminal; all the fruit is shriveled and the foliage, usually a deep purple this time of year, is curling and falling to the ground. There have been signs of rust for a couple years, but this is by far the worst. Unfortunately, there is a bank of 5 cedar trees within 70 feet of this crabapple. Should we give up and cut it down?
Steve
Thank you for your response. Though the rust disease is not supposed to kill the tree, it certainly looks terminal; all the fruit is shriveled and the foliage, usually a deep purple this time of year, is curling and falling to the ground. There have been signs of rust for a couple years, but this is by far the worst. Unfortunately, there is a bank of 5 cedar trees within 70 feet of this crabapple. Should we give up and cut it down?
Steve
Since you have cedars close by, this will be a persist issue. In moist seasons like we had last year and into this spring, fungal diseases tend to be worse than in drier years, so there will be some variability from year to year. It is really up to you whether to keep the tree or cut it down. If you find that it has value for providing some shade and/or supporting wildlife, you can certainly keep it. If you want one that is less susceptible to rust, replace it with a disease-resistant cultivar or another type of tree.
Christa
