Ailing Arizona cypress trees might be past their prime

Q: I have three Arizona cypress trees on the west side of my backyard in the Northeast Heights here in Albuquerque. The bark on all three is peeling away, which I know is normal for an Arizona cypress. However, there is a lot of sap dripping in some places and some of the bark that is coming off is much thicker than I think it is supposed to be. I had the trees pruned and tidied up last September. They have been getting watered for the past 4½ years that I’ve lived here on the property with them. I estimate their age between 45 and 55 years old. What can be done for my trees, so they regain some vigor? Thanks for any advice you can provide. — J.B., Albuquerque

A: I have always envisioned these types of trees planted to encircle farmsteads as wind breaks. They can grow, if planted appropriately, as a living screen of sorts, which to me looks like how your Arizona cypress were originally planted. You know, sort of as a property line.

The first two things I did when I received your note was to Google two things. First was “average lifespan of Arizona cypress,” then “pests affecting Arizona cypress.”

The answer to my first query doesn’t bode well for your trees. I found several sites that suggest, on average, your variety of cypress lives 35-to-50 years. The age does depend on how the trees were/are maintained, several environmental stressors and insect attacks.

So, let’s say your trees are 50 years old. Initially when they were planted, I’m thinking, they were maintained. Meaning they were watered appropriately, maybe fertilized, and perhaps treated for any pests that were noticed by the homeowner for the next, let’s say, 15 years. Then, God knows. Maybe the original planter aged-out so to speak, maybe the house became a rental property and the landscaping wasn’t tended to as well as could have been done for the next 30 years. Next, the weather threw in a few hard balls to give the trees a more difficult time.

Then, luckily, you come along and start to care for these guys. But for approximately 30 years, give or take, there is no diary as to how the trees were tended. Except nowadays, they are showing signs of stress.

The next sites I looked at cautioned a wicked pest called bark beetles. When trees are stressed, they emit a pheromone that bugs smell, knowing that the tree sending out that signal will make a great home for them. Since the tree is under duress, it’ll be easier to invade.

If there is a bark beetle invasion, that would in my opinion explain the dripping sap you’re describing. Sap dripping is usually a sign that the tree is aiming to push a bug or fungus out. It’s usually done by trees to attempt to heal themselves. Sometimes it works, but more times than not that dripping sap opens other avenues for a whole host of other troubles. I don’t know if your cypresses are infected by bark beetles or if something else is troubling them, other than their age.

What I will suggest is that you hire a tree doctor to come and diagnose the state of your trees. If a plan can be hatched to lengthen the health of your trees, here’s hoping. Just recognize that your cypress trees are perhaps reaching the age when they have given you their all and it might be time to consider removal. You certainly don’t want the trees to fail and fall on the nearby wall. With the ever-changing environmental pressures that these struggling trees are facing, it could very well be time to hedge your bets and sacrifice the trees for safety’s sake. Definitely invest in a professional opinion, not a fly-by-night company, but a real arborist to guide you for the health of your Arizona cypress.

Good luck and Happy Diggin’ In!

Tracey Fitzgibbon is a certified nurseryman. Send garden-related questions to Digging In, Albuquerque Journal, 7777 Jefferson St. NE, Albuquerque, N.M. 87109, or to features@abqjournal.com.