I have noticed mature Acer macrophyllum trees in pierce county (Washington State) that show signs of distress. They produce much smaller leaves and large amounts of seeds. After these trees show this habit, they usually die before the end if the year or do not leaf out the next spring. I have seen this on dozens of trees. Does anyone know of any diseases that could cause this? Thank You, Jake
Trees of this species sampled in the Seattle arboretum some years ago had more than one kind of water mold attacking their roots.
Verticillium is one thing that can affect that mape. But could it be due to some other change in the environment - something from the past 1 to 20 years? Maybe it's not a disease. Just for a change of pace, look at the image below. I was called to do consulting about the condition of Douglas firs locally. What I saw standing next to the tree was suffiicient to recommend removal, including fungal conks all up the trunks. But I wondered if the cause could be found. I drove up the hill to see if someone had a view that could be related to previous topping. That did not pan out. Anyhow, I looked at the area in Google Earth for no real reason other than a quick glance. Then something caught my eye. There were 4 dead tree tops in that wooded area. And we could almost draw a straight line through them. I don't think it is a coincidence. Still have no idea what the cause is. But believe that something occured along a line or path in there in the past 10 to 80 years. The red arrows point to the dead tops which are lighter color.
If they could have worked along a 20 degree slope through 100 year old trees - possible. It had crossed my thoughts whether a buried shallow ridge of bedrock - if fairly straight - could cause problems to trees over decades if the depth of earth limited water during drought.
I live across the water from Seattle. What should I know about these various kinds of water mold? What were they, for starts? Will they be problematic for the palmatums? Can you provide a link to a precis about the tests? Should I worry about preventative maintenance specifically in relation to water mold? Or should (theoretically) plating my maples high and ensuring proper drainage be the most effective "protection"?
As I remember it one or more Phytophthora spp., Pithium and maybe another genus. Haven't seen anything in print on the sampling and results. A party that used to post here frequently said some grafted Japanese maples were being distributed with Pseudomonas infections that caused failure later, after establishment on the final planting site. The online pdf catalog of Heritage Seedlings has a side bar about Pseudomonas and what they are doing to prevent their stock from becoming infested. Verticillium Wilt is often blamed for the frequent dying back of Japanese Maple cultivars. Vertrees/Gregory, Japanese Maples (Timber Press) has a multi-page discussion of Japanese Maple diseases.
Yes a good an updated information but the FAQs in this forum have an even more detailed explanation Gomero
In the FAQ that doesn't mention Pseudomonas in the title or description, or until the sixth post of the thread, of course; I think it may be a classified or top secret FAQ: "Blackened tips and twigs in spring". (There is some very good information in the thread, it's just not easy to find if you are looking for a FAQ about pseudomonas.)
That's correct Maf. I chose that title (instead of, say, psudomonas affections) since most people come to the forum asking what happens to their maples with all those tips and twigs blackening, they do not know it is pseudomonas. However it is true the FAQ does not give explicit advice on how to avoid the infections (though this could be easily inferred from the explanation there), the text in Heritage Seedlings catalog is more usable in that respect. Gomero
Very true, the title is relevant and very helpful for those people, but if some other person were looking for info on pseudomonas in the FAQs section, it would not be immediately obvious that there was any such information available. For example if someone had heard about pseudomonas and wanted to look up what the symptoms were. Maybe it would be possible to mention "pseudomonas" in the paragraph to the right of the title. Gomero, it is hard to comment on this subject without it sounding like criticism of the FAQs, which is not my intention at all. I appreciate your contribution in putting the FAQs together. Thanks again, maf
