Does anyone know if the Acer Silver Cardinal is susceptible to verticillium wilt? Dazzled by the red branches and striped bark and varigated leaves, I impulsively bought an Acer Silver Cardinal 2 years ago and now I hesitate to plant it in my soil which I know (but temporarily forgot) has the fungal disease. It is grafted, but I don't know what on. Currently it is doing very well in a 2 gal pot. Could I plant it in a large, above-ground cement or wood container? Thanks for any help! Di
yes, very susceptible. Probably grafted on rufinerve, which is also susceptible to the wilt. Opinions differ about whether verticillium stays in the soil, but if everything you plant gets it, I'd leave Silver Cardinal in a pot. Good luck, -E
On Camano Island I have had problems with multiple maples which I am pretty sure are due to pseudomonas infestations. The site adjoins an obvious water and cold air drainage, probably making atmospheric conditions excellent for pseudomonas. Especially if you are on the flats perhaps that is what you have as well, instead of verticillium. Have you had the pathogen tested and identified by WSU? Otherwise a formerly active poster here has said that sloppy propagation practices in some wholesale production facilities has resulted in grafted Japanese maples in particular being sent out pre-infested with pseudomonas, which continues to develop and manifest itself after purchase by the final consumer. So that might be something else you may have had happen at least part of the time. In my experience a tendency is to call dieback of Japanese maples especially "verticillium" when it may not be that particular agent in every case at all.
thanks for the responses. I read the other threads about the wilt. I lost a smoke bush after a year or two in the ground. I hauled the whole thing in to the WSU extn Master Gardeners and every one agreed it was vw. (it was the actual class and one of the scientists was teaching--I don't remember who) no test except visual was done. Since then I check lists before chosing what to plant. It is just that there are a few maples listed that are supposed to be less susceptible and I thought someone might know about this particular maple. I am on the west side of the hill, not the flats, at the site of an old apple orchard. I have also lost a clerodendron and a styrax to similar symptoms. on the other hand, the cercis Forest Pansy and Parrotia are going like a house afire after 8 or so years in the ground. too bad I bought it on impluse. it was rather pricey. any thoughts on a container? when I bought it I thought it might be fun to try pollarding it about 6 feet so the red stems could be enjoyed. di
The Cotinus might have been infested when you bought it or otherwise not indicate that your whole site is infested or hopeless. I had one blight off years ago but it did not keep doing it later and nothing around it has shown such problems. Likewise an existing, self-sown vine maple died back after I spread some muck-like (peat) soil near it, implying the new soil was infested. Again, although the maple was spoiled that was the end of an apparent infestation of the site. With each failed plant there is a specific set of circumstances that occurred. Some may be lost to or spoiled by multiple pathogens, others may have merely drowned, dried up or frozen out. Testing of declining native bigleaf maple root samples taken from the Seattle arboretum found multiple kinds of root pathogens present, including phytophthora and I think armillaria. I see signs of this last rather often in this area, particularly on old hybrid rhododendrons. Last year I lost one of my best garden specimens (a bigleaf magnolia) to this, the "fingers of death" (my term) being evident near the base. Honey colored mushrooms coming up where a mildewed-to-nearly-nothing 'Unique' rhododendron had been cut down but otherwise left in place also served as a hint. Come spring the tree did not leaf out, soon after I was able to push it right over. That's what armillaria does, it decomposes dead wood - sometimes making its own dead wood by killing trees and shrubs near the base, instead of waiting for them to die from other causes.
Ron, so sorry about your magnolia and the rhododendrons. you remind me a plant can die for many reasons. I am remodeling my small garden (my entire lot) and I have been remembering all the plants I have lost over the last 10 years. after reading your post, I am inclined to just give it a try and plant the Silver Cardinal. It isn't doing any good sitting in a 2 gallon pot for 2 years. Time to take the risk! the place I am putting it has had the most pathetic hardy fuschia and I finally pulled it out yesterday. in they come, out they go....if they make it, my friends think I am a genius, otherwise, it goes in the yard recycle bin. I have seen those armillaria in mushy spots on spongey wood, but I hadn't thought about them destroying living trees. what beasts! Di
British gardening references have long advocated removal of dead stumps from woodland gardens because of the armillaria problem. If you have a small patch of problem soil you might consider excavating and replacing it before installing additional choice specimens. Of course, if there is an infestation (or drainage problem etc.) that extends beyond the excavated area future difficulty may come in from the sides. Or you might see a significant improvement.