# Japanese Maples: Black Bark - Fungal Infection or Dieback **URL:** \ **Category:** Horticulture\ **Created:** [March 19, 2019, 9:56am UTC](https://forum.bonsaimirai.com/t/japanese-maples-black-bark-fungal-infection-or-dieback/2838 "2019-03-19T09:56:30Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![Max](https://yyz1.discourse-cdn.com/flex029/user_avatar/forum.bonsaimirai.com/max/32/3897_2.png) [@Max](https://forum.bonsaimirai.com/u/Max)\ **Post date:** [March 19, 2019, 9:56am UTC](https://forum.bonsaimirai.com/t/japanese-maples-black-bark-fungal-infection-or-dieback/2838/1 "2019-03-19T09:56:30Z")
Hello everybody, over the past few years I observed sometimes black coloring of bark of Japanese maples. I ask myself if that’s always a fungal infection, or if dieback, caused by wrong cuts etc also takes on this black color? What are your experiences? Here are some pictures… Max ![IMG_1427](https://canada1.discourse-cdn.com/flex029/uploads/bonsaimirai/original/2X/8/85d57bf705c9a5339689131d1e95561e0600a39a.jpeg) ![image](https://yyz1.discourse-cdn.com/flex029/images/transparent.png) ![image](https://canada1.discourse-cdn.com/flex029/uploads/bonsaimirai/original/2X/2/2b58652eeb58aaac82037275a15df16cdb92b4e9.jpeg) ![image](https://canada1.discourse-cdn.com/flex029/uploads/bonsaimirai/original/2X/9/98e492538a42640fe4a56eab126498e6e00238b4.jpeg) ![9106e046-da54-4e50-8fd9-6bf56173ea4a](https://canada1.discourse-cdn.com/flex029/uploads/bonsaimirai/original/2X/e/eae5e8406b7d5ea57b7ea1fc617f62f9125ced51.jpeg) ---
**Author:** ![Heliostar](https://avatars.discourse-cdn.com/v4/letter/h/f14d63/32.png) [@Heliostar](https://forum.bonsaimirai.com/u/Heliostar)\ **Post date:** [March 19, 2019, 3:02pm UTC](https://forum.bonsaimirai.com/t/japanese-maples-black-bark-fungal-infection-or-dieback/2838/2 "2019-03-19T15:02:58Z")
Hi Max, This could very well be Verticillium wilt. > **[Maple (Acer spp.)-Verticillium Wilt](https://pnwhandbooks.org/plantdisease/host-disease/maple-acer-spp-verticillium-wilt)** > > See also: Verticillium Wilt in the Pacific Northwest Cause Samples with Verticillium wilt have dominated the maple problem diagnoses sent to the OSU Plant... ---
**Author:** ![Max](https://yyz1.discourse-cdn.com/flex029/user_avatar/forum.bonsaimirai.com/max/32/3897_2.png) [@Max](https://forum.bonsaimirai.com/u/Max)\ **Post date:** [March 25, 2019, 2:54pm UTC](https://forum.bonsaimirai.com/t/japanese-maples-black-bark-fungal-infection-or-dieback/2838/3 "2019-03-25T14:54:57Z")
Heliostar, thanks a lot for the link! Max ---
**Author:** ![Max](https://yyz1.discourse-cdn.com/flex029/user_avatar/forum.bonsaimirai.com/max/32/3897_2.png) [@Max](https://forum.bonsaimirai.com/u/Max)\ **Post date:** [April 1, 2019, 8:53pm UTC](https://forum.bonsaimirai.com/t/japanese-maples-black-bark-fungal-infection-or-dieback/2838/4 "2019-04-01T20:53:49Z")
Here is another example… I tried to bend the lower part of the trunk and wired a new leader in autumn… ![image](https://canada1.discourse-cdn.com/flex029/uploads/bonsaimirai/original/2X/9/98c71f957770ae41a2c047c4fb83fe81388caf27.jpeg) Buds did not open this spring. As I removed the clamp I recognised that the bark turned black at the points of contact. Pressure too high on the bark, I think. Below the wire there is also a black area. ![image](https://canada1.discourse-cdn.com/flex029/uploads/bonsaimirai/original/2X/a/a22ce21fa52e99888595d77503fa332f73fc7e9c.jpeg) The roots looked good to me. I have no idea why this tree died. Maybe the bend was too heavy? I did the same clamp bending with another young maple. Same blackening of contact points. But he is doing well. ---
**Author:** ![Colorado\_Josh](https://yyz1.discourse-cdn.com/flex029/user_avatar/forum.bonsaimirai.com/colorado_josh/32/4080_2.png) [@Colorado\_Josh](https://forum.bonsaimirai.com/u/Colorado_Josh)\ **Post date:** [April 3, 2019, 5:01pm UTC](https://forum.bonsaimirai.com/t/japanese-maples-black-bark-fungal-infection-or-dieback/2838/5 "2019-04-03T17:01:30Z")
My Corel bark did something similar over the winter. I attempted to use snow as an insulator in the early winter. It got to -5f in December. The snow was against the trunk. It was there where the black appeared. Right now there is back budding below the black, and death above. I’m going to wait to trunk chop it until I’m positive I know what died. Kind of bummed. Maybe it will be a good shohin, since the trunk us only 4" tall now. I wonder if your bend stressed the cambium layer. ---
**Author:** ![KurtP](https://yyz1.discourse-cdn.com/flex029/user_avatar/forum.bonsaimirai.com/kurtp/32/16188_2.png) [@KurtP](https://forum.bonsaimirai.com/u/KurtP)\ **Post date:** [November 7, 2019, 3:53pm UTC](https://forum.bonsaimirai.com/t/japanese-maples-black-bark-fungal-infection-or-dieback/2838/6 "2019-11-07T15:53:08Z")
Sad. Did you replace the tree? ---
**Author:** ![Max](https://yyz1.discourse-cdn.com/flex029/user_avatar/forum.bonsaimirai.com/max/32/3897_2.png) [@Max](https://forum.bonsaimirai.com/u/Max)\ **Post date:** [November 7, 2019, 7:50pm UTC](https://forum.bonsaimirai.com/t/japanese-maples-black-bark-fungal-infection-or-dieback/2838/7 "2019-11-07T19:50:02Z")
Hi Kurt, the maple in the colander did not make it, also the one in the ground. The one in the first picture is healthy. I put him in the ground this spring. Max ---
**Author:** ![Keith-in-UK](https://avatars.discourse-cdn.com/v4/letter/k/f04885/32.png) [@Keith-in-UK](https://forum.bonsaimirai.com/u/Keith-in-UK)\ **Post date:** [November 8, 2019, 9:00pm UTC](https://forum.bonsaimirai.com/t/japanese-maples-black-bark-fungal-infection-or-dieback/2838/8 "2019-11-08T21:00:31Z")
I think you’ll find it is Pseudomonas syringae which is often mistaken for verticllium wilt. It can be controlled. Michael Hagedorn has written an article about it. This is the page (not very good at copying links!!!). [https://crataegus.com/2011/11/29/read-](https://crataegus.com/2011/11/29/read-) **this-if-you-grow-japanese-maple** ---
**Author:** ![Michael\_P](https://yyz1.discourse-cdn.com/flex029/user_avatar/forum.bonsaimirai.com/michael_p/32/10657_2.png) [@Michael\_P](https://forum.bonsaimirai.com/u/Michael_P)\ **Post date:** [November 9, 2019, 10:17am UTC](https://forum.bonsaimirai.com/t/japanese-maples-black-bark-fungal-infection-or-dieback/2838/9 "2019-11-09T10:17:59Z")
> [@Keith-in-UK](#): > > [https://crataegus.com/2011/11/29/read-](https://crataegus.com/2011/11/29/read-) **this-if-you-grow-japanese-maple** Fixed link: > **[Read This If You Grow Japanese Maple](https://crataegus.com/2011/11/29/read-this-if-you-grow-japanese-maple/)** > > This post is about a common bacterial disease called Pseudomonas syringae, which frequently affects Japanese maples yet is relatively easy to control. It is often misidentified as Verticillium wilt… ---
**Author:** ![Keith-in-UK](https://avatars.discourse-cdn.com/v4/letter/k/f04885/32.png) [@Keith-in-UK](https://forum.bonsaimirai.com/u/Keith-in-UK)\ **Post date:** [November 9, 2019, 8:25pm UTC](https://forum.bonsaimirai.com/t/japanese-maples-black-bark-fungal-infection-or-dieback/2838/10 "2019-11-09T20:25:56Z")
Thank you @Michael_P. That makes it easier for everybody…