Row of 16 year old emerald green arborvitaes 44 total. about 1/3 of them have a brown spot or dead spot on them. And all of them have yellowed tips. Could this be wind damage or something more? Never had a problem since planted. They are about 18' tall. Live in Massachusetts.
There are several possible causes for dieback on arborvitae branches. Winter kill, lawn chemicals, pruning so an area, often the bottom, doesn't receive enough sunlight and water stress. There may be a bit of life in the browned areas. Keep them watered this growing season before pruning out the dead-appearing branches next year. There is a canker that affects Aborvitae, Seiridium canker. It is most common in Leyland cypress but arborvitae can be affected, too. The following link takes you to an article on this disease. https://hnr.k-state.edu/extension/info-center/common-pest-problems/common-pest-problem-new/Arborvitae%20Seiridium%20Canker.pdf
i HAVE TWO 18 FT. ARBORVITAES ALONG THE SIDE OF THE HOUSE, WITH NO COMPETING PLANTS. I'M IN SC. WE HAD A PARTICULARLY HARSH WINTER WITH SEVERAL NIGHTS IN THE TEENS. NO SNOW. IT'S IN THE 90'S AND 100'S NOW, AND QUITE A FEW OF THE BRANCHES ARE TURNING BROWN, WITH QUITE A BIT OF NEEDLES FALLING TO THE GROUND. NOT SURE IF THIS IS A CASE OF THE 1 WEEK OF EXTREME TEMPERATURES, OR A LACK OF PROPER FERTILIZER, OR SOME KIND OF DISEASE. ALSO, IF YOU CUT AN ARBORVITAE OFF AT THE TOP,WILL THAT HELP TO SPUR GROWTH, OR WILL IT KILL THE TREE? TIA, dAN MAHONEY
Unless you know that the type you have is tolerant of this pruning i would advise against it. The harsh winter is likely the cause, and it can recover, but it may need help. They can be left exposed to fungal infection upon these conditions, especially with wet conditions. I would recommend adding wettable sulfur to the areas around the affected plants. This will kill off any infection, and help the tree to recover.
https://www.gardeningknowhow.com/plant-problems/disease/using-lime-sulfur-in-gardens.htm
These conifers are around 15-20 years old, but some look like they’re dying . Any ideas what’s happening?
This appears to be a fungal infection. This can happen when the season is overly wet, or from over irrigation.
You will likely have to remove the trees heavily affected, as they will never fully recover. I would treat the area with a fungicide as well, before planting. This article will help: https://www.gardeningknowhow.com/garden-how-to/info/using-fungicides-in-garden.htm
This article will help you to care for Arborvitae: https://www.gardeningknowhow.com/ornamental/trees/arborvitae/growing-arborvitae-trees.htm
the soil to protect the bush? Why does this happen, and how can I avoid this in the future?
I looked at several references and didn't find any that suggested using a systemic insecticide, but rather treating with a spray in May or June. These articles should help:
https://www.gardeningknowhow.com/plant-problems/pests/insects/treatment-bagworms.htm
The trees are planted in 40 liters containers 5 years ago. My zone goes from full summer (up to 34c) to harsh winter (-5c).
This can have a few causes. Colder than usual weather is the most common. Other reasons can include sun burn, lack of nutrients (This is very likely in container) and fungal infections from wet weather.
These articles will help:
https://www.gardeningknowhow.com/ornamental/trees/arborvitae/winter-damage-to-arborvitae.htm
https://www.gardeningknowhow.com/ornamental/trees/arborvitae/fertilizing-arborvitae-trees.htm
https://www.gardeningknowhow.com/ornamental/trees/arborvitae/growing-arborvitae-trees.htm
I have a newly planted 6 foot Emerald cedar that replaced 2 that were frozen out over these past two winters. What is the best wrap to cover it with & what technique do I use? I was told by Richardsons Greenhouse in Navan where I purchased the cedar to not use burlap, to wrap around the tree not touching it, leaving the top exposed. Please advise what is right. Thank you
Wrapping an Arborvitea can, definitely, help it to survive a harsh winter. Here are some sources that will help you with this task: https://www.canr.msu.edu/news/act_now_to_manage_snow_damage_on_arborvitaes
https://www.gardeningknowhow.com/ornamental/trees/arborvitae/winter-damage-to-arborvitae.htm
https://www.gardeningknowhow.com/plant-problems/environmental/protecting-plants-winter.htm
https://www.gardeningknowhow.com/plant-problems/environmental/winter-burn-in-evergreens.htm
https://www.gardeningknowhow.com/plant-problems/environmental/plant-covering-materials.htm
We planted 20 trees approx. 2ft. tall in March '18. All of them are starting to look like they are going to die. We had lots of rain over the summer and not once did we need to water them manually. We are experiencing a rather rainy season. We need your help, please!
They do need plenty of water till they are well established. But their roots do not like to sit in soggy soil. Is yours a well drained location? I imagine you have lots of humidity there and that can lead to fungal problems such as blight, which is controlled by pruning out the affected branches and starting a fungicide routine.
I suggest calling your local extension service where they can give a more definitive diagnosis with more information.
https://www.gardeningknowhow.com/ornamental/trees/arborvitae/growing-emerald-green-arborvitae.htm
https://www.gardeningknowhow.com/ornamental/trees/arborvitae/growing-arborvitae-trees.htm
https://www.gardeningknowhow.com/ornamental/trees/arborvitae/fertilizing-arborvitae-trees.htm