The Edmond Sun

Features

November 14, 2013

Stress causes pine tree needles to turn yellow

EDMOND — Q: Why are my pine tree needles turning yellow?

A: When the needles on a pine tree turn yellow, the first reaction is that the tree has a disease or insect problem. But evergreen needles do not stay green forever. The older, inner needles discolor and naturally drop off after one or more years, depending on the species of pine.

Some years, the needles on a pine will yellow and drop unnoticed by the homeowner. In other years, a large number of needles yellow at the same time in late summer or early fall, making for a striking display. Because the condition is triggered by the weather and other stress factors, many evergreens are likely to show symptoms at the same time.

Austrian pines are the most dramatically affected trees in Central Oklahoma. This species typically maintains three years of green needles in the summer. But during a year with stressing weather conditions, the Austrian pine may only maintain the current year’s needle growth. Second- and third-year needles turn yellow throughout the tree. Sometimes, the last two years of growth will remain green with the third year’s growth turning yellow. The tree will appear particularly unhealthy if the yellowed needles outnumber the green ones of the current season.

All of this is a part of the natural needle drop that occurs in pines. Each species of evergreen tends to keep its needles for a defined length of time. Austrian and Scotch pine usually retain needles for three years. Japanese black and red pines will often retain green needles for four years before the needles yellow. Arborvitae needles usually turn brown instead of yellow as they age. This plant will hold needles much longer than pine.

Yew needles turn yellow and drop in the late spring or early summer instead of fall. They usually drop third-year needles unless stressed. It is not uncommon in tight clay soil for a yew to exhibit prominent yellow needles in the spring. These are usually second-year or even third-year needles that yellow and drop due to plant stresses. Spruce and fir needles also yellow and drop with age. But since these trees retain their needles for several years, needle drop is often not visible to the homeowner.

Be careful not to confuse natural seasonal needle drop with various insect and disease problems that might be life threatening to the plant. The fact that needle drop is a seasonal occurrence and that the symptoms are distributed throughout the interior part of the tree helps distinguish natural needle drop from other problems.

There is no way to control or reduce natural needle drop in an evergreen plant. Keep evergreens healthy by following good cultural practices. It is a good practice to irrigate evergreens thoroughly going into the winter. Since evergreens maintain needles year round, the plant continues to lose moisture in the winter. An evergreen plant in dry soil is more prone to winter injury through desiccation. Also, continue to examine evergreens on a regular basis for evidence of disease or insect problems.

RAY RIDLEN is an agriculture/horticulture educator for the OSU Extension Center, 930 N. Portland in Oklahoma City. He may be reached at 713-1125.

1
Text Only
Features
  • Shopping smarter for family necessities can help the environment

    There’s a growing trend among consumers to make choices reflecting the goals and values that matter to them most.  In fact, two out of five people say they’re more inspired to try a natural product that does something good for themselves, their family and the planet, according to a recent study conducted by Toluna for natural products brand Tom’s of Maine.

    July 21, 2014

  • Back to school lunch Build a better bag

    Brown bag lunches and back to school go hand in hand. As you’re gearing up for the start of a new school year, it’s the perfect time to stock the pantry with healthy sack lunch options and after school snacks, too.

    July 21, 2014 1 Photo

  • Pets

    This is a list of animals that have been found and are at the Edmond Animal Shelter, at Interstate 35 and Covell in the Cross Timbers Municipal Complex. Call the shelter at 216-7615 for more information.

    July 21, 2014

  • Kids Cook Simple ways canned foods get children cooking

    When it comes to teaching children about healthy eating habits, there’s no better classroom than the kitchen.

    July 21, 2014 1 Photo

  • Garden Vegetable Spring Rolls The Canebrake offers summer recipe for Garden Vegetable Spring Rolls

    The Canebrake, a destination hotel and spa in Wagoner, is offering the following recipe from its restaurant for Garden Vegetable Spring Rolls with Avocado Wasabi Puree.

    July 21, 2014 1 Photo

  • Malaysians wonder 'Why us?' after second loss of airline jet

    It was all too familiar. Grieving families rushing to airport. The flashing television graphics of a plane's last radar appearance. The uncomfortable officials before a heavy thicket of microphones.
    For many Malaysians, the disappearance of Flight 370 in March has been a long trauma from which the nation has not yet recovered.

    July 21, 2014

  • Quilt Edmond Quilt Guild celebrates 10th anniversary with event

    Quilting has evolved over the years and now, more than ever it is looked at as an art form.
    Edmond’s Quilt Guild is sponsoring its fourth quilt show and festival celebrating its 10th anniversary at the same time this week and inviting area residents to come and check out some of the newest types of quilting.

    July 19, 2014 1 Photo

  • Ryan by horse statue.jpg Good Samaritan who lost his leg ‘Keeps Moving Forward’

    He is an uncommon hero, this Good Samaritan who saved another man’s life and in doing so lost his left leg. Now his friends and family are reaching out to help him.
    While assisting a stranded motorist on Nov. 9, 2011, Edmond resident and Santa Fe High School graduate Tyler Ryan was hit and pinned against the back bumper of a car by an inattentive motorist on 15th Street in front of Crest Supermarket.

    July 18, 2014 1 Photo

  • Arthritis Foundation names Devon Energy Corp. CEO as 2014 honoree

    The Arthritis Foundation this week announced that John Richels, Chief Executive Officer, Devon Energy Corp., will be this year’s honoree at the 25th Annual Tribute to Excellence Dinner scheduled for Oct. 22 at the Skirvin Hilton Hotel in downtown Oklahoma City.  Richels will be recognized for his leadership, commitment and dedication to charitable and civic causes in the communities Devon serves across Oklahoma and throughout North America.
    The Arthritis Foundation’s Annual Tribute to Excellence Dinner recognizes outstanding Oklahomans in the public and private sectors for their exemplary work, as well as for their personal and professional contributions to society.

    July 18, 2014

  • Garden Yard of the Week winner Thompson preserves local history, beauty

    There is always movement and activity around the outskirts of the University of Central Oklahoma campus, but this week’s Edmond’s Yard of the Week winner, Sharon Thompson at 631 N. University, calms the area with a combination of Edmond’s slower past history and a current Zen peacefulness of nature in harmony. Her home is adjacent to more Edmond history — Gossett Park, honoring a 50-year Kiwanis member.

    July 18, 2014 1 Photo