when inner conifer needles turn yellow or brown

DON’T PANIC: Nothing’s wrong, and they’re not all dying in unison, I promise. Though we commonly call them “evergreens,” conifers such as pine, arborvitae, spruce and Hinoki cypress (above) lighten their load of old needles in late summer and fall, with a show of yellowing or browning that can scare a gardener at first.

This phenomenon should not be confused with browning at the tips or overall yellowing or browning that can happen at other times—such as from winter desiccation; from the effects of roadside salts; from pests and diseases (including diplodia tip blight in some pines or phomopsis in spruce and non-resistant junipers); or from drought. (See what road-salt damage and winterburn look like by comparison in these photos.)

The browning I noticed in late July on my Eastern red cedar in the front yard (Juniperus virginiana) is suddenly showing up as gold or rusty-brown or a progression from one to the other on many other conifer species. The Eastern white pines (Pinus strobus), above, with their long needles, are always the most dramatic, turning what looks like mostly gold. Hard to believe the plant will be OK.

But in fact needle-drop is a normal part of the life cycle, though the rate varies by species, and can also accelerate if environmental stresses like dry conditions or pest infestation have affected the tree or shrubs in a given season.

Before you call the arborist in, though, go inspect: Look at a branch closely (such as in the Thuja occidentalis, above), to identify where along it the fading foliage is. I found the illustration below on a Michigan State University Extension factsheet, showing the natural aging and shedding cycle (again, it varies by species how long till leaves are shed).

The losses should generally be from the inside out, not at the branch tips. Inner needles are the oldest, and as they age and get shaded by new growth farther out, they photosynthesize less effectively and are eventually shed. The plant lightens its load, and good thing, since snow and ice may be coming and extra needles could hold too much weight for the longer branches to bear.

All conifers do this, just in varying degrees (that’s a Thuja plicata just above), and at various speeds from every couple of years to every five or longer. In fact some, such as metasequoia and bald cypress and larch, do it thoroughly every year–the so-called deciduous conifers. But that’s another story.

Speaking of evergreens: Some broadleaf ones such as Rhododendron will be pushing off old, useless foliage now, too. The only thing I’m worrying about there: the big old leathery foliage is falling into the frogpond and making the tenants angry. As the official janitor, my workload is temporarily increased, but if I don’t keep up I could have an amphibian riot on my hands.

factsheets on fall browning of conifer needles

28 comments
October 8, 2012

comments

  1. Rachel says

    Margaret, it’s like you’re reading my mind! Yesterday, on a walk around the reservoir and garden I volunteer at, I got really worried that a bunch of “evergreens” were dying. But this is the precise way their needles were browning. Thanks for the reassurance.

  2. Trixie says

    Thanks for posting this. It is so timely! Just this week I noticed some yellowing parts on a few cypress and got worried. I already started planning in my head what I might put in their place, should they bite the dust. Relieved to know this is likely just part of their normal cycle.

  3. says

    Hi Margaret,
    I also have several Hinoki cypress in my yard which have turned yellow as in your photo. My lawn men told me to strip off those leaves. Do you agree? Also, do you pluck off the ends of the branches of the Hinoki to encourage less height and more girth, or do you think the natural growth is better for the trees? I am concerned about these trees in my yard as I was unfamiliar with them yet allowed them to be planted. (Never will make this mistake again!) I may have to move them as they are in the foundation plantings and growing rapidly. Thanks so much for your advice. I enjoy your posts. Linda

  4. says

    Once again, Margaret, such a timely and helpful post. I noticed this on my arbovitaes and started to push the panic button….whew! How I would replace those lovelies I’ll never know. Now I can put my attention into worrying about something else out there! :)

  5. says

    Hi Margaret, this is one of the more frequent questions that I receive in emails beginning mid summer to fall. Most new, and some not so new, gardeners don’t realize this happens. I’ve scheduled your page to post on our Facebook Fan Page tomorrow afternoon (Tuesday, October 16th).
    Thank you,
    Cheryl Jones
    Greenwood Nursery

  6. Beverly, zone 6 eastern PA says

    I absentmindedly allowed 4 voluptuous gourd vines to escape their confines and use my Arborvitae Hedge as a trellis. We needed a stepladder AND a pole pruner AND a towel-padded wash basket to cut and catch 31 weighty dipper and bottle gourds. While we climbed up a ladder inside the hedge, we shoved lower branches out of the way and jostled those above us. The naturally-shedding brown needles coated my hair, my arms, went inside my shirt, my bra and eventually ended up all over the bathroom rug when I disrobed for that evening’s shower. I like them better when they stay outside, but it’s good to know it’s a naturally occurrence.

  7. frani says

    Hi Margaret, I listened to your podcast about conifers. Wonderful as always! We have a live tree for christmas. Would any of the lovely conifers you talked about be able to survive a week in the house as a christmas tree? And then be planted outside? I live in bucks county pa, zone 6.
    Thanks for all of your inspiration, Frani

    • says

      Hi, Frani. I think it’s the same for all of them — you have to keep them as cool as possible and inside as short as possible. I suspect the concolor fir (popular as a holiday tree cut too) might be a goodie to try.

  8. says

    Thanks for this great post. In the Southwest, we experience bark beetles and so needle drop is always a cause for alarm. It’s important to remember to water in the winter if there hasn’t been much precip as pests love those weak trees. I also clear out the needle from the interior of dense mugos (which I should prune) in order to avoid more needle drop due to lack of sun, air flow etc. Unfortunately I wore a short sleeved shirt and had a terrible rash from needles. Just a note of caution. Love your site and the good information. Thanks!

    • says

      Hi, Polly. I get a rash on the inside of my forearms from some junipers, I think. (I used to have some here; don’t at the moment.) Good point! Nice to “meet” you (and yes, time for some lightening up on some of my overstuffed-with-old-needles dwarf white pines here too!).

  9. DeLinda Owens-Llewellyn says

    Thank you, Margaret. The excellent pictures were very helpful, reading about plant symptoms is one thing, a picture tells all. ( Your pictures are always particularly good. )

    DeLinda

  10. joan packer says

    Martgaret,
    You are so lucky to have those lovely frogs so I guess you will have to work hard and keep their pond clear!

  11. Judy says

    Hi Margaret,

    Thank you for posting this. I have two small cypresses by my front door… and, for a few years, the needles have turned brown.. especially toward the center. The outer part looks good and has growth and is full. However, the back of the shrubs look pretty bald. I guess it’s because that part is not too exposed to the sun. It’s good to know that the browning part is normal.

  12. Joellen Curtis says

    My Hinoke cypress is all brown with tinges of green through out , it has been very cold here in Michigan. I planted in the fall on the south east corner of my house , I sprayed with wilt Pruf and put up a wind shield as Hinoke extends out of protection of the house about 3 ft, just wondering if the brown turns back to green in the spring?

  13. lisa ratza says

    My Hinoki Cypressturned almost totally brown and the other one third brown.
    is there a chance it will com back?
    Should I clip off the brown branches?We did have a devastating Winter!!!!

    Lisa Ratza

    • margaret says

      Hi, Lisa. Sounds extreme. Certain varieties can get winterburn in a windy/too sunny spot in the cold season. I never do anything until I see if the plant intends to “push” new growth — so it may be a little early to be certain how much is dead, and how much just damaged. It’s normal for the INNER foliage to brown off and drop periodically, but not the outer. The trouble with trying to correctively prune is that you can’t cut Hinoki cypress back past the fresh newish wood…the inner wood doesn’t have the potential to make new buds and push new growth. So if the damage goes deep into the plant, it won’t regenerate. Sounds from your description that the damage is severe (which I would expect to be permanent) but again: I’d just wait a little longer to see if there are any signs of life, particularly in the one that’s less damaged.

  14. Lind Sayre says

    I just recently transplanted two lea land pines they were a year old. The inside by the trunk is all turning yellow. Does this mean too much water or not enough. Please help I don’t want to lose them.

  15. Ed says

    Thanks for the post on interior browning of confers. I have 8 Spartan Jupiters that I purchased from a nursery last fall and are experiencing the same problem thin summer in the 100 degree Texas sun. The only other problems I have noticed have been slight winter discoloration on the Southwestern sides, and seems to be some webbing lately from spider mites? that needs attention. Should I simply but the 3 in 1 tree solution to take care of any current issues, or try to focus solely on the mite problem? I am noticing individual twig clusters dieing on select branches, but not near the tips or affecting any one individul branch completely. I am wondering if this isolated cluster browning on various locations of all the trees is being caused by the insects or perhaps not enough water. We are in a semi drought situation this year, and due to strict watering restrictions, the tress may not be getting enough moisture so soon after being planted. How much weekly water would be normal at this point in time? Again, its been 1 year now, and they are each approx 8 -10 ft tall & 3 -4 ft wide.

    • margaret says

      Hi, Ed. I do think the too-little-water stress is encouraging your other troubles, yes. Multiple stressors allow a pest to get the upper hand, whereas in a normal weather year you might have less pressure from them. Newly transplanted trees or shrubs, whose roots aren’t settled in yet, means yet another layer of stress for these plants. Read this NCSU factsheet on juniper problems to see if in fact you have mites (it explains how to put down a sheet or paper and bang on a branch to dislodge and count them) and this one (if it is mites!) from Colorado State.

      • Ed says

        Thank you,

        Yes watering is most likely part of the overall problem. I try to water once a week by drip line (approx 2-4 gal?) regardless of allowed scheduled days or normal rainfall precipitation. I will look further into pest control, but can you suggest an amount / time to water per tree based on my current situation. I am afraid of over watering since I have lost other types of trees in the past due to water logged issues in this heavy clay soil environment.

        Ed

  16. says

    Hi Margaret..What lovely photos of the Roach girls!!. My garden is covered with pine needles…
    under the trees it is five inches thick in some places. In the past i have used the needles for mulch under the roses…but it seems that is a bad idea. I will eventually rake them all up to
    the fence (about 50 ft..long) but any suggestions on what could be done with them? It is a very tall pine tree (seven of them)…They are about 50 ft or more tall. The active growth is way
    up at the top, but there are a few branches at lower levels. I keep them as they shield me from traffic noise and they are pretty with the sunset behind them. As always….my very best
    wishes…I wish Copake Falls was not so far from Easton! Anne

leave a reply

Your email address will not be published. Required fields are marked *