What You Need To Know About Christmas Tree Mold and Christmas Tree Syndrome

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This year, Americans will buy 25-30 million live Christmas trees to decorate their homes for the holidays. About 85% of those trees will be pre-cut weeks ahead of time – in most cases prior to Thanksgiving. The trees are cut, baled and packed into refrigerated trucks to be delivered to a tree seller near your home.

For some, bringing a live Christmas tree into their home is a recipe for disaster. Why? Christmas Tree Syndrome.

A lot of Christmas trees with the overlay text of "what you need to know about Christmas tree mold."

What Is Christmas Tree Syndrome?

In short, Christmas Tree Syndrome is a seasonal illness of varying intensity which as its name suggests is caused by your Christmas tree (and in some cases your Christmas wreaths too)! The allergic condition is caused by the presence of a Christmas tree in an enclosed indoor space.

Nearly 50 years ago, a Canadian researcher wrote a paper entitled “Christmas Tree Allergy: Mould and Pollen Studies,” in which he noted that about 7 percent of individuals with allergies experienced a rise in their symptoms when they had a Christmas tree in their homes. His small sampling of 10 homes uncovered a variety of mold spores and not much credence was attributed to his findings, but the term Christmas Tree Syndrome was born.

Nearly 40 years after the Canadian research article, interest in Christmas Tree Syndrome reappeared. This is because 1 in 3 people will develop Christmas Tree Syndrome at some point in their lives.

Causes of Christmas Tree Syndrome include:

  1. Mold spores
  2. Pollen
  3. Terpenes – These chemical compounds are known for giving pine trees their natural scent and can also cause irritation in some individuals.
  4. Pesticide use
  5. Dust Mites
  6. Insect droppings – pests can inhabit your live tree or artificial Christmas tree storage space and leave droppings that aggravate allergies.

What Are The Symptoms Of Christmas Tree Syndrome?

Man blowing nose. He has Christmas Tree Syndrome

Research done at the State University of New York Upstate Medical University found that 70% of the molds found in live Christmas trees can set off reactions like severe asthma attacks, fatigue, and sinus congestion.

Symptoms of Christmas Tree Syndrome will depend on the person’s genetic makeup, overall health, predisposition to allergies, previous mold exposures, and whether or not they are currently battling mold related illness or CIRS.

Common symptoms include:

  • Asthma attacks
  • Dark circles under eyes
  • Eye, nose and throat irritation
  • Fatigue
  • Headaches
  • Illness (like colds and other viruses)
  • Nosebleeds
  • Rashes
  • Runny nose and/or nasal congestion
  • Sneezing
  • Wheezing/difficulty breathing

Is Christmas Tree Syndrome Dangerous?

While in most cases, the condition has only minor side-effects and symptoms, it can apparently worsen respiratory problems for asthmatics and in some extreme cases lead to pneumonia which can be life-threatening.

Tell Me More About Christmas Tree Mold

A Christmas Tree Farm where the trees are at risk for mold

Christmas trees are coniferous softwoods, which naturally hold a lot of moisture. Combine this with slow decay and it’s inevitable that mold will begin to form, particularly in a warm household environment.

In addition, when live trees are precut, packed, and shipped, along the way moisture and the tight bundling of the trees supports an ideal environment for mold to grow.

A study in 2007 which was presented at The American College of Allergy, Asthma & Immunology Annual Scientific Meeting in Dallas, examined the relationship between mold growth on live Christmas trees and poor indoor air quality.

Twelve times during a two week period, researchers measured mold counts in a room containing a live Christmas tree, beginning when the tree was brought inside and decorated. The tree was located 10 feet from a heat vent, and the indoor temperature was maintained at between 65 and 68 F.

The study found that the mold spore count was 800 spores per square meter (m3) for the first three days. Normal spore counts are less than 1,000 spores/m3, said Hemmers. However, the spore count rose after day four, reaching a maximum of 5,000 spores/m3 by day 14 when the tree was taken down.

Researchers at St. Vincent’s Medical Center in Bridgeport, Connecticut, found that a room containing a fresh Christmas tree for two weeks had mold levels that were five times the normal level.

Another scientific study by allergy specialist, Dr. Lawrence Kurlandsky at Upstate Medical University in New York set out to determine why respiratory illnesses peak around Christmas. The study found 53 different types of mold, including, aspergillus, penicillium, cladosporium and alternaria.

See an issue here? That live Christmas tree just allowed mold spores to go wild in your home and wreak havoc on your health.

While the other causes of Christmas Tree Syndrome are legit and a problem, Christmas tree mold is the worst and mot dangerous offender.

What About Christmas Tree Ornaments and Other Christmas Decorations

Glass balls for Christmas Tree to prevent mold growth

When it comes to Christmas tree ornaments, lights, garland and other tree décor, the main issue is cross contamination. The same goes for Christmas decorations that have been stored WITH anything adorning your moldy Christmas tree.

The issue of cross contamination is a very serious issue.  When you store Christmas tree ornaments and other Christmas decorations that have been on a Christmas tree with mold, you have basically just given them license to grow mold in a nice cozy environment. Even if mold growth does not occur, you now have a ton of Christmas stuff covered in dormant mold spores.

What does this mean?

First, you immediately contaminate next year’s Christmas tree. This is particularly bad if you made the switch to an artificial tree. You have also just re-released mold spores into your home. Given the right moisture conditions, these spores may take root and grow elsewhere in your home.

The second issue with Christmas tree ornaments and the like are the type of material they are made out of. Porous items cannot be cleaned as the mold spores are rooted too deep. These items must be thrown out. Non-porous items stand a chance of being cleaned so long as you use something like EC3 Mold Spray or Citrisafe, both which knock out mold and mycotoxins.

What Types Of Christmas Tree Ornaments Won’t Grow Mold?

Mold spores can stick to anything, but there are some fairly safe non-porous Christmas ornaments and Christmas decorations. Let’s take a look at the ideal Christmas décor.

  • Glass ornaments (these are my favorites)
  • Metal ornaments (I have a few of these)
  • Wooden ornaments that are sealed with varnish (varnish adds protection to the pores and puts a barrier between the wood/food that mold requires to grow)
  • Metal figurines and other Christmas décor (this metal Nativity set is cute)
  • Plastic, glass, porcelain, metal or glass beaded garland (this is my top Christmas tree garland pick)

What Types Of Ornaments And Christmas Decorations Should You Avoid?

You won’t like this list. But if you want to prevent mold in your home, you really do need to steer clear of these types of items.

  • Anything made from paper
  • Anything made with cotton
  • Baskets
  • Cards and wrapping paper
  • Decor made with moss
  • Decor made with tree trunks or branches
  • Felt ornaments
  • Foam decor
  • Fuzzy garland
  • Leather décor
  • Pillows
  • Popcorn string garland
  • Raw wood decor and ornament
  • Real garlands or wreaths
  • Stuffed animals and fabric holiday figures
  • Wicker decor
  • Yarn anything

Unfortunately there are a lot of household items in general that are prone to mold growth. Be sure to check out the full list above as some of your holiday decor may fall into another material category.

A decorated Christmas Tree in front of picture windows on a wood floor. Caption reads "how to prevent Christmas Tree mold."

How Do You Prevent Christmas Tree Mold?

The obvious answer is don’t purchase a live Christmas tree. Instead, opt for an artificial tree. This artificial Christmas tree is a really good choice as it is also eco-friendly.

  1. If you are using an artificial Christmas tree, I would first clean it with EC3 Mold Spray. Allow it to dry and then spray it with Superstratum Mold and Mildew Protectant. This will prevent mold from growing on your artificial tree for years to come!
  2. If you do opt for a live tree, before you bring the tree into your home, wash it first! Set a hose to a hard spray to get into the nooks and crannies. Then spray it all over with EC3 Mold Spray. This will deactivate any existing mold. Wait for the surface to dry off, and then spray Superstratum all over the tree to prevent mold spores from forming. This residue will remain on the tree for the duration of the holidays.
  3. Some studies have shown that a properly cleaned live Christmas tree is safe for indoor display for 4 days only. Kind of a lot of work for 4 days but if you really want a live tree, this might be your work around.
  4. If you choose to go with the live Christmas tree, buy a self-cut tree. A self-cut tree has not been exposed to higher mold spore levels associated with storage and transportation.
  5. Unpack all of your Christmas décor outside and before bringing them inside, wipe everything down with EC3 Mold Spray. If you prefer to use another cleaner stick with a borax, baking soda OR ammonia solution. But don’t mix these together.
  6. Clean air will also reduce mold exposure. Run an air purifier in the same room as the live tree to lessen the effects of any rogue spores in the atmosphere.
  7. Purchase non-porous holiday decorations and ornaments.
  8. Dust and clean all of your Christmas decorations before storing them away again. Make sure they are dry before packing them away.
  9. Use plastic storage totes and not cardboard boxes.
  10. Place a moisture absorber like this one inside each storage tote. These little pouches will absorb any excess moisture that might happen to sneak inside the tote. You will need to replace these yearly.
  11. Wrap fragile items in plastic bubble wrap and not newspaper.
  12. Do not store your totes of Christmas decorations in a basement, crawl space, or attic.
  13. Store all Christmas decorations and totes at least one foot off the ground, ideally on racks to allow for air flow.

The Christmas holiday should be a time of celebration and joy, not illness and suffering. Take the proper steps to keep yourself Christmas Tree Syndrome free and enjoy a mold free holiday!

A beautiful Christmas tree in a decorated living room

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  1. Hi,

    In cleaning Christmas tree decorations, you write “wipe everything down with EC3 Mold Spray”. Could you please explain how to do that. I have EC3 Mold Spray but it says to spray items and let them dry. So, I’m not sure what you mean.

    1. Hi RJ! I will reword that section. I see how it can be confusing. You can spray and let the items dry. On some surfaces the EC3 might leave water marks. What I was getting at is that it is ok to either soak a cloth in EC3 and wipe everything with that, allowing it to air dry OR spray it and them wipe off any water marks after the EC3 dries. Does that make more sense?

  2. Linda Boland says:

    Our dog has diagnosed tree, mould and weed allergies. We just put away our artificial Christmas tree. He was miserable every day it was up but alot better now. I read on your website about a borax solution to clean the tree. Do you have a recipe for this. My basement isn’t damp, will this be ok for storage in a tree bag or canvas? Thank you for your reply.

    1. Hi Linda! You want to mix 1 cup of borax with 1 gallon of warm water. Obviously make sure the tree is totally dry after cleaning before storing it. Your tree should be fine in a bag or canvas. If you don’t have mold or moisture issues in your basement then it will be ok to store it there. Ideally you will not lay it directly on the ground but on a wire rack a foot or so off the ground (or more).

      For your pup – have you ever tried these? https://www.amazon.com/Allergy-Immune-Supplement-Peanut-Butter/dp/B079TWY9FK/ref=as_li_ss_tl?crid=1E6QC0RCJG24M&keywords=dog+allergy+medicine&qid=1578333066&sprefix=dog+alle,aps,271&sr=8-9&linkCode=ll1&tag=hybrasmam-20&linkId=fd762892bf5440b8a1396b7973014301&language=en_US They work amazing for dog allergies!

      Let me know if you have additional questions!

  3. I am reading the studies and wonder if they were done on you cut Christmas trees or pre cut as I assume this makes a difference? We have done an organic you cut tree and I’m wondering if that’s still releasing mold spores at such high levels after five days?

    1. Hi there! This would be an interesting study. I believe that a pre-cut tree carries a slightly elevated risk of coming into a home already replicating mold spores. But honestly once the tree gets into the house the conditions are even better for mold to flourish whether the tree is pre-cut or not.

  4. I am so glad I found your article! Thank you for this information. This is the first time we’ve bought a tree from a lot and have been experiencing weird symptoms the last week or so. Getting rid of the tree immediately!

    In the article you mentioned cleaning what was possible as far as Christmas decor. What about the rest of the house? Should I be concerned abo it my furniture and things?

    Thanks again, seriously!

    1. Hi Tristen! No, I would not worry about it. The tree wasn’t in there long enough to do major house wide spore spreading. I would just give your home a thorough HEPA vacuuming.

  5. Hi there! We recently removed an extremely moldy (visible on branches) live tree from our home.
    Our whole family was sick with upper respiratory illnesses. We are still not feeling great. What other steps should we consider taking in our home? There is not much information about the home other than ornaments and decorations. Thank you o

    1. Hi Amy! I am very sorry to hear this! I would personally look into fogging your house. This is a non-toxic way to get rid of the cross contamination and it can be done yourself. Here is my article on fogging. Please take a look and email if you need further advice specific to your situation. https://moldhelpforyou.com/best-mold-control-fogger/