Is another reason to avoid Norway maples needed?

18

Leafspot
Photo by JP Thimot.

It’s been a bad year for maple trees. Norway and silver maples across the Northeast and Midwest are ravaged this year by tar spot (the Rhytisma acerinum fungus) and (maybe less widespread) anthracnose, as I posted on GWI last week.

In Western New York, the Norways look the worst; their shriveled leaves have been falling since August. The silver maples (shown at top) aren’t quite as bad. If I needed another reason to dislike these trees, this blight provides it. Apparently, the soaking we got in May gave the fungus what it needed; it is visible almost every year, but usually not so much that we don’t get some decent color.

Treatments other than conscientious leaf removal (which I always do anyway) are not advised by the various extension sources I’ve consulted, and I’m glad there are no plans by the city to carpet bomb the streets with fungicide. I did hear of one possible remedy—though I’m doubtful. A Facebook friend contacted me after my GWI post, and said she noticed the problem in midsummer and her arborist did this: “provided in-ground injections of concentrated fertilizer. Within one week, the tree markedly improved, and has been fine since that time.”

I’ve never fertilized any of my trees, other than the usual additions of mulch and compost to the garden beds that surround them, and I’d never heard that injecting fertilizer would help with disease. Well, I’m only vaguely aware of the practice of injecting fertilizer—I’ve certainly never done it.  Interesting!

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Elizabeth Licata

Elizabeth Licata has been a regular writer for  Garden Rant since 2007, after contributing a guest rant about the overuse of American flags in front gardens. She lives and gardens in Buffalo, N.Y., which, far from the frozen wasteland many assume it to be, is a lush paradise of gardens, historic architecture, galleries, museums, theaters, and fun. As editor of Buffalo Spree magazine,  Licata helps keep Western New Yorkers apprised about what is happening in their region. She is also a freelance writer and art curator, who’s been published in Fine Gardening, Horticulture, ArtNews, Art in America, the Village Voice, and many other publications. She does regularly radio segments for the local NPR affiliate, WBFO.

Licata is involved with Garden Walk Buffalo, the largest free garden tour in the US and possibly the world,and has written the text for a book about Garden Walk. She has also written and edited several art-related books. Contact Elizabeth: ealicata at yahoo.com

18 COMMENTS

  1. I think they are Crimson King. Anyway, these are street trees, which–unless they fall down on their own–I cannot replace. And if one did fall down, I wouldn’t replace it with any tree. It’s really a question of “enough with the trees” on my street.

  2. Sigh. I have such fond memories of the Norway maple in my grandma’s yard. It was just the right size for a nine year old to climb. With those thick leaves I could sit up there and be totally invisiable to the next door teen age boy washing his car in their drive. It was my first major crush and I only wanted to worship from afar.

  3. There are so many nice trees out there, but I have 2 Norway maples in my front yard that belong to the town. There is no fall colour, and the leaves drop late. Why couldn’t I have a nice sugar maple instead?

  4. Ohh I’m right with you there — I’m currently sitting in Plant Pathology class looking at so many Norway Maple pathogens and diseases and they just look ugly. I’m a fan of the Silver Maple that’s native to here in Ontario

  5. A Norway maple was planted 20 years or so in front of a local library to provide a good climbing tree for young library patrons. It did its job, but has been slowly dying. Now, with a new library addition, the library landscape is getting a renewal. The Norway maple is coming down and a new climbing tree planted. Once they decide which new climbing tree. Any ideas?

  6. I’ve heard of similar treatments being applied for fungal disease called black spot on Aspen trees here, but it is usually in conjunction in with the application of mychorrizae, which is what is supposed to help the tree overcome the fungal disease. The fertilizer is just to help the tree with its overall health. At least in theory.

  7. Fertilizer does not cure the leaf spot fungus, but disguises it by pushing the growth of new leaves. The new leaves have not been subjected to the environmental conditions that caused the initial fungus, so they remain unspotted. By the time the leaf spots are noticeable there’s no cure for the damage, except to keep the fungus from spreading (which is rarely a problem), and in most cases leaf spot is an aesthetic problem only.

  8. Norway maple: Invasive non-native tree. Who needs any other reason than that?
    Silver maple: Native, but fast grower with weak wood that makes it prone to split in high winds. Very good for carbon sequestration, though. Plant it in the back 40 where nothing will be harmed if it drops limbs.

  9. @Eliz – the leaves on Crimson King is bright purple year round but I totally hear you on “enough with the trees”

    @commonweeder – there used to be a program whereby one could buy clones of historic american trees (Johnny Appleseed apples, trees from various historic settings, president’s houses and so on and even clones of trees grown from seeds that went to the moon). I reckon there’d be something perfect for the library amongst them if you can find the nursery website (a google search has failed me).

  10. Ah! Sorry Eliz; totally missed the silver maple ref to the picture (and evidently didn’t look close enough to note the species difference). Now I really hear you with “Enough with the trees”!

  11. Tar spot is not a major issue. Just unsightly. The major issue with these large maples is the ever encroaching root zones that choke out lawns.
    Since this is an anti-lawn forum these trees should be right up your alley

    The TROLL

  12. I dont know what kind of Maple grows in Michigan but mine all have that by the end of the year, especially if its a dry summer. Would like to know how to avoid it
    Janice

  13. Thanks for the info, Elizabeth! We unfortunately have a silver maple as do most of the neighbors on our block. I hate the fungus spots on our leaves, but I don’t know if injecting fertilizer into the ground is worth the bother at this late date.

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