hawthorn Crimson King problems - Ask Extension
Three hawthorn Crimson King trees, planted 4 years ago and very healthy up to now, started to defoliate a few weeks ago. The leaves on some branches ...
Knowledgebase
hawthorn Crimson King problems #586403
Asked August 05, 2019, 8:47 AM EDT
Three hawthorn Crimson King trees, planted 4 years ago and very healthy up to now, started to defoliate a few weeks ago. The leaves on some branches turned brown first, and now some branches are bare. Nearby are 3 fothergillia that have started to brown off. We also had an infestation of caterpillers on our baptisia, which you diagnosed. We have not watered this garden this summer. The problem with the trees and fothergillia started earlier in the summer when we were getting enough rain.
Talbot County Maryland
Expert Response
In your second photo, it looks like there is significant damage to the tree trunk. Is there a split in the trunk? If there is a significant physical injury to the trunk, it cuts off a portion of the water/nutrient transport system of the tree. It cannot take up the water it needs and the result will be dieback and decline in the canopy. It also looks like the tree was planted too deeply. A properly planted tree should show the top of the root system flaring out at the base. Planting too deeply can lead to bark decline at the base of the tree and eventually kill the plant. https://extension.umd.edu/hgic/topics/planted-too-deeply
Can you tell us when you planted the Fothergillas? Is just one plant showing symptoms or do all three have the same issue? If the leaves have just gone brown (no other symptoms like leaf spots, chewing, holes), then it is most likely a water deficit issue. If they were newly planted within the last two years, they may not have fully established their root systems into the native soil -- and were not getting sufficient water.
Christa
Can you tell us when you planted the Fothergillas? Is just one plant showing symptoms or do all three have the same issue? If the leaves have just gone brown (no other symptoms like leaf spots, chewing, holes), then it is most likely a water deficit issue. If they were newly planted within the last two years, they may not have fully established their root systems into the native soil -- and were not getting sufficient water.
Christa
Thank you for your response. One hawthorn tree trunk was damaged by deer antlers the first year it was planted. It continued to grow very well for the next several years. The other two tree trunks were never damaged, but they have the same defoliating problem now. We planted them above grade, but I guess they have settled some, and the mulch may be a little too close. We know to be careful with the mulch and we never mound it around the trunk. Could there be something else going on here, a disease or insect? The trees were planted early May, 2014.
The fothergillas were planted on May 30, 2014. This summer, the leaves on one plant dried, turned brown, and curled one branch at at time. Then a few weeks later the second one started. Now all three have the problem. The first one gets the most sun. We watered carefully the first two years but have depended on rain since.
The fothergillas were planted on May 30, 2014. This summer, the leaves on one plant dried, turned brown, and curled one branch at at time. Then a few weeks later the second one started. Now all three have the problem. The first one gets the most sun. We watered carefully the first two years but have depended on rain since.
Thank you for your response. One hawthorn tree trunk was damaged by deer antlers the first year it was planted. It continued to grow very well for the next several years. The other two tree trunks were never damaged, but they have the same defoliating problem now. We planted them above grade, but I guess they have settled some, and the mulch may be a little too close. We know to be careful with the mulch and we never mound it around the trunk. Could there be something else going on here, a disease or insect? The trees were planted early May, 2014.
The fothergillas were planted on May 30, 2014. This summer, the leaves on one plant dried, turned brown, and curled one branch at at time. Then a few weeks later the second one started. Now all three have the problem. The first one gets the most sun. We watered carefully the first two years but have depended on rain since.
The fothergillas were planted on May 30, 2014. This summer, the leaves on one plant dried, turned brown, and curled one branch at at time. Then a few weeks later the second one started. Now all three have the problem. The first one gets the most sun. We watered carefully the first two years but have depended on rain since.
I was so focused on the trunk damage and planting depth issues in my first reply, but in your first photo, there are also signs of rust disease on the foliage (the reddish blotches) that I did not call out. Hawthorn rust is a fungal disease that uses hawthorn and Juniper trees as alternate hosts. Trees with high infections can have significant leaf loss in the summer. It is difficult to manage if there are Juniper trees nearby (up to several miles away) since the spores with spread back and forth between the two hosts. The best long-term management option is to plant disease-resistant varieties of hawthorn. Several types are listed in this article. https://ag.umass.edu/landscape/fact-sheets/cedar-hawthorn-rust
We do not recommend a fungicide for this, has homeowner sprays tend to be impractical/ineffective.
https://extension.umd.edu/hgic/topics/rust-diseases-trees
It also looks like there is some caterpillar chewing damage on the trees. Typically most shade trees can handle some chewing damage and no control is needed.
The symptom in the Fothergillas appears to be environmental in nature, given the symptom and the pattern. It could be a soil problem -- either too dry or too wet. Many trees and shrubs suffered from the record-breaking amount of rainfall we had last season. It can take a long while before a shrub shows any negative effects. Things like being planted too deeply and too much mulch can also cause decline. Fothergillas have a shallow root system so anything that impedes the roots can cause a problem.
Christa
We do not recommend a fungicide for this, has homeowner sprays tend to be impractical/ineffective.
https://extension.umd.edu/hgic/topics/rust-diseases-trees
It also looks like there is some caterpillar chewing damage on the trees. Typically most shade trees can handle some chewing damage and no control is needed.
The symptom in the Fothergillas appears to be environmental in nature, given the symptom and the pattern. It could be a soil problem -- either too dry or too wet. Many trees and shrubs suffered from the record-breaking amount of rainfall we had last season. It can take a long while before a shrub shows any negative effects. Things like being planted too deeply and too much mulch can also cause decline. Fothergillas have a shallow root system so anything that impedes the roots can cause a problem.
Christa
