Young white spruces dropping green needles
I am from Nova Scotia, Canada and recently planted several 2 ft white spruce trees along the western edge of my property in late Dec. Last month I noticed one of the trees showed extensive patchy needle loss closer to the bottom of the tree. The numerous needles I found on the ground are still green. Another tree close by I recently noticed had a similar issue but more towards the top of the tree. Again lots of green needles on the ground. However this tree also shows brown needles and half brown/half green needles still on the tree. Just wondering what this may be. Thanks for any help you could provide.
Outside United States
Thank you for contacting us about your spruce. Winter can be especially difficult for new trees, particularly if they did not have time to establish some new roots before the ground froze. You might want to continue caring for them for a few months to see if they recover, although I would not be hopeful about the tree in the third photo.
It is very difficult to diagnose plant problems without an actual inspection. I doubt you have a pest problem but there may be root problems.
Were the trees potted or balled and burlapped when you planted them? If so, the current best practices recommend that you remove all of the packaging and try to gently wash off as much of the soil as possible. This allows you to inspect the roots and spread them out in the planting hole. Do you know what the condition of the roots was at planting?
Have your trees received consistent water through the winter? The winter winds can desiccate conifers, so it is essential that they receive enough water.
I cannot tell from your photos, however, but the trees may have been planted too deeply. The trunk flange should be visible above the soil line and mulch should be kept well away from the trunk.
As a footnote, staking is no longer recommended for most trees. If properly planted, staking is not needed and may actually create weaker root systems.
Hello and thanks so much for taking the time to help.
I actually had them planted by a landscaping company who I believe transferred them from pots, 12 trees in total. I am unsure of the root conditions unfortunately.
I was also told they wouldn't need water until the spring and then whenever there is a large stretch without rain. No doubt this certainly played a role and I am fortunate the other trees seem ok. How much and how often should I water them?
I have attached a picture showing some black and white fuzzy string like material on the trees. Is this normal?
Also, everything that could cause issues with trees seem to turn the needles brown and then fall. However, I seem to have considerable green needles on the ground. Is that of any significance?
Finally, I moved some of the mulch away from the trunk and removed a root accidentally so they seem weak. Apart from watering, is there anything else I could do to help them?
I really appreciate your time and assistance. Thank you.
I'm sorry your landscaper was not able to provide you with better information. Landscapers do not always stay on top of changes in plant husbandry. Often there is some sort of guaranty on live plant material so you might want to contact the landscaper before you take other steps.
I am not familiar with your weather conditions, but newly planted trees need between 1 and 2 inches of water per week for the first few weeks, and then at least 1-inch per week thereafter. This amount includes rain, snowmelt, and irrigation. As long as the soil is not frozen, tree roots will continue to grow and need moisture, especially in windy conditions which will dry the foliage. You might dig up the weakest plant and inspect the roots. They should look healthy, not black, shriveled or dried out.
It is somewhat troubling that you encountered roots when removing the mulch. The roots should be covered with soil, and the soil is then covered with mulch. The mulch should always be at least 6-inches away from the trunk. Mounding it against the trunk can retain moisture on the bark and lead to disease and pest problems.
If you are satisfied that the trees have been properly planted and mulched, the best thing to do is ensure they get the required amount of water each week, then wait to see what happens. Do not fertilize stressed plants because this can force new foliage growth which puts additional stress on them.
This article may provide you with some useful information about needle drop: https://gardening.usask.ca/articles-disorders/why-is-my-evergreen-turning-brown.php Your local Master Gardeners may be able to help also.
I hope this information is helpful. Good luck with your little forest, and feel free to let us know how your trees fare over the summer.