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mbohio13

Arborvitae Help - Black, Brown & Spiders

MBOhio13
9 years ago

We planted six 6' emerald green arborvitae a few months ago. They took great at first, but in the past month or so, they're starting to struggle. I'm noticing 3 main things:
1) toward the bottom of the trees, some of the needles are turning a dark, tar black. This seems to be limited to the bottom of the trees.
2) some of te internal branches are turning a little brown.
3) There are some spider webs that have recently formed in a few trees.

Regarding the black and brown, there are two things that I think might be causing this. A) I've noticed my dog peeing on the trees lately (we can get them to stop); and B) our neighbors have an irrigation systems that they seem to put on every single night and the trees are just inside the property line, so they get a lot of water from their system and the ground around the trees is sopping wet and swampy. Does anyone know what the black and brown needles are from and do either of these 2 suspected causes make sense?

Also, what should I treat the trees with the get rid of the spiders? I've heard they are fine as long as they are not overwhelming the trees, but wanted to throw this in for the sake of completeness.

I apologize for the basic questions, but I am just learning about gardening and tree care! Thanks in advance for your help!

Comments (5)

  • ken_adrian Adrian MI cold Z5
    9 years ago

    spiders are our friends.. ignore them ... they will be gone after the first frost ...

    trim out the black and throw it away ..

    keep dog away .. train properly ...

    if not planted last spring.. but planted in mid summer.. not the best timing ... transplant shock would be possible .... do NOT be surprised if you get a lot of INTERIOR yellow ... either this fall or next late spring ....

    i dont know about the neighbors.... if mine wanted to water my plants.. i dont know if i would argue... lol ... he ought to be blowing out his system for winter soon enough ....

    can we see a pic of whole trees ... i suspect you are doing better than you are worrying about ...

    IGNORE THE SPIDERS ....

    ken

  • MBOhio13
    Original Author
    9 years ago

    Thanks for the feedback Ken, which is super appreciated.

    About the dogs, this is an easy fix. We actually have an invisible fence and we cut the line when planting the trees because the line also runs right along the property line! We just need to splice the fence line (planned for this weekend) and then the dogs will stay away.

    About the water, I totally agree that it's awesome to have neighbors watering our trees for free! However, because the ground seems so swampy, I started to wonder if the trees were actually being over-watered, which I thought might be contributing to the black/brown.

    I will post below with additional photos. They do not look terrible, just not as great as the first month or so after planting, so I wanted to get ahead of any problems, rather than ignoring early signs and having them die on us later.

    They were planted right in the middle of July, which I know is a terrible time to plant, but they were SUPER discounted, so it was worth the risk at that time.

    Based on what I have explained and these photos, what do think overall, did I overreact?

    And aside from stopping the dogs from peeing, it sounds like I should also trim off/out any black and brown needles, right? Should I do that right now or is there a better time in the Fall to do it?

    Thanks again!

  • MBOhio13
    Original Author
    9 years ago

    Another photo of more of the trees - there are 2 others too, but I think this photo gives you the gist.

  • Jill Lockett
    4 years ago
    last modified: 4 years ago

    Hi, I realize this post is pretty old but I am having the same issue with my newly planted Arbs. Did you ever find out the cause or how to fix them ?

  • User
    4 years ago
    last modified: 4 years ago

    Probably best to start your own thread including pictures and history of planting, watering etc.

    Many here don't like to respond to old threads resurrected.

    Welcome to the forums! :^)