juniper shrubs turned brown -big time - Ask Extension
Hello, I need help with a juniper problem. I don't see insects, so suspect it's a fungal situation? I didn't notice this dying off last year but I'm g...
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juniper shrubs turned brown -big time #790495
Asked May 12, 2022, 3:46 PM EDT
Hello, I need help with a juniper problem. I don't see insects, so suspect it's a fungal situation? I didn't notice this dying off last year but I'm guessing it was already being attacked and i didn't see it. I'll probably remove the shrub #1 but don't know if it must be bagged and destroyed, or can it go to the recycle center composting? Do the roots need to be removed?
Any hope for saving shrub #2 with a spray? And if so, what should I use?
Thank you,
Sally Rose
Isabella County Michigan
Expert Response
Good Morning,
There are many causes for juniper browning.
Browning and dying branch tips may indicate an insect infestation such as spider mites. You can check for this by holding a piece of white paper under a juniper branch and shaking it. Look at any small specks that fall on the paper through a magnifying glass. If you see brown, red, green or yellow eight-legged insects, your juniper has spider mites. Your junipers are browning in more than just the tips, so this is likely not the issue. You should check for this critter anyway to be sure. Insufficient and excessive watering can cause browning. Consider how much or how little you water these plants. Entire branches dying back especially on larger shrubs or juniper trees may be due to twig blight. This is caused by cankers. This disease can also cause foliage on infected branches to turn yellow or brown and wilt. A canker is a localized dead (necrotic) area on branches, trunks or roots. Cankers vary greatly in appearance but are often a circular or oblong lesion that may be discolored, oozing or sunken. Below is some additional information.
Though junipers will tolerate a neutral to slightly alkaline soil, they are acid-loving plants that grow and look their best in an acid to neutral soil ranging from 5.5 to 7.0 on the pH scale. Because your junipers are planted in soil covered with rocks, your soil may be too alkaline for healthy growth. It would be a good idea to conduct a soil test to ascertain your soil's pH level and also to learn if there are any needed nutrients that you can add. Junipers also appreciate well-drained soil. If your soil is clay, this could be another contributing factor. Home | MSU Soil Test
Before composting I suggest you get a firm diagnosis. You will want to destroy any diseased portion of the tree. These pictures should be emailed to our MSU Plant Diagnostic lab, where professional pathologists will look for needle disease evidence. They may request you send in a branch sample( if they do there is a fee charged to examine live samples, as is explained on the website). The lab email is <personal data hidden>
The lab website with instruction for submitting live samples is https://www.canr.msu.edu/pestid/
Another option is a consultation with a certified arborist. An arborist will come to your property and can evaluate the plants, the planting methods and the environment. Some arborists will do an initial consultation at no cost.
http://www.treesaregood.com/
References
https://hortnews.extension.iastate.edu/2002/5-10-2002/brownjuniper.html
Juniper Diseases & Insect Pests | Home & Garden Information Center (clemson.edu)
Juniper Diseases - Trees, Lawns, and Landscaping (psu.edu)
I hope this helps. Thanks for using our service
There are many causes for juniper browning.
Browning and dying branch tips may indicate an insect infestation such as spider mites. You can check for this by holding a piece of white paper under a juniper branch and shaking it. Look at any small specks that fall on the paper through a magnifying glass. If you see brown, red, green or yellow eight-legged insects, your juniper has spider mites. Your junipers are browning in more than just the tips, so this is likely not the issue. You should check for this critter anyway to be sure. Insufficient and excessive watering can cause browning. Consider how much or how little you water these plants. Entire branches dying back especially on larger shrubs or juniper trees may be due to twig blight. This is caused by cankers. This disease can also cause foliage on infected branches to turn yellow or brown and wilt. A canker is a localized dead (necrotic) area on branches, trunks or roots. Cankers vary greatly in appearance but are often a circular or oblong lesion that may be discolored, oozing or sunken. Below is some additional information.
Though junipers will tolerate a neutral to slightly alkaline soil, they are acid-loving plants that grow and look their best in an acid to neutral soil ranging from 5.5 to 7.0 on the pH scale. Because your junipers are planted in soil covered with rocks, your soil may be too alkaline for healthy growth. It would be a good idea to conduct a soil test to ascertain your soil's pH level and also to learn if there are any needed nutrients that you can add. Junipers also appreciate well-drained soil. If your soil is clay, this could be another contributing factor. Home | MSU Soil Test
Before composting I suggest you get a firm diagnosis. You will want to destroy any diseased portion of the tree. These pictures should be emailed to our MSU Plant Diagnostic lab, where professional pathologists will look for needle disease evidence. They may request you send in a branch sample( if they do there is a fee charged to examine live samples, as is explained on the website). The lab email is <personal data hidden>
The lab website with instruction for submitting live samples is https://www.canr.msu.edu/pestid/
Another option is a consultation with a certified arborist. An arborist will come to your property and can evaluate the plants, the planting methods and the environment. Some arborists will do an initial consultation at no cost.
http://www.treesaregood.com/
References
https://hortnews.extension.iastate.edu/2002/5-10-2002/brownjuniper.html
Juniper Diseases & Insect Pests | Home & Garden Information Center (clemson.edu)
Juniper Diseases - Trees, Lawns, and Landscaping (psu.edu)
I hope this helps. Thanks for using our service
