Roots

[uncle K]

Our townhouse association has 30 year old ficus trees in each front yard. They have been trimmed/shaved annually, to maintain a shape like a wheel of cheese. They actually look quite nice, plus, they provide a privacy shield from the street, a large measure of shade from the burning desert sun (warmest, driest place in the US), and they're habitat for a variety of birds. All good.

Our sister association just removed their ficus trees, citing a handful of sewer and foundation problems. Even as our division is about 5 years older, we've only had one incident, a garage floor which was lifted. We're trying to shrug this off, because these mature trees are well worth the maintenance expense... so far. Today, I saw another previously unreported garage floor which is quite distorted from ficus roots. Ruh roh.

Trouble is coming, no doubt. Removing them would have a huge impact, so I'm a wishin' and a hopin' there is a way around that.

1. Is it possible to cut the creeping lateral roots, say, beyond the drip line (stalling the problem for years to come) without killing the trees?

1. If we have to remove them, we have to replace them with something. Is there an ideal tree, which will grow up fast, be reasonable to maintain, but not repeat the root invasion process?

Some of you with desert life experience are probably familiar with this love/hate relationship with ficus trees, and have this figured out. No?

TIA for any ideas.

Unc

[HeyBub]

The basic rule for pruing plants (above ground) is to remove no more than

1/3 of the folage a year. I presume, though I do not know, that the same holds true for roots.

That said, a ditch-witch could prune the roots in the direction of harm quite easily.

[uncle K]

They've been maintained to about a 25-30' diameter, about 25' tall. The trunks are about 1 1/2' diameter.

Yuma

The do seem to be weeds, and they do take plenty of abuse, yet they are green and healthy looking.

[uncle K]

I've seen ditch-witches in action. As long as they know where the sprinkler lines are, that would be much more practical than men with shovels and saws.

[uncle K]

Yes, not my favorite subject, but that can't be helped and life goes on.

No, I don't think so. I'm familiar with PNW trees. The desert is a different world, and I'm trying to learn something here, instead of guessing.

We have some inexpensive Jacks of all trades for small jobs, but long ago, learned that licensed and bonded contractors are needed for anything on this scale.

[Tony Miklos]

A ditch witch would be my plan... that is if I were growing trees in a desert. ???

[Edward Reid]

Cut the roots -- with that much to do, use a ditch witch, as suggested. Find out how deep the horizontal roots go -- the tree may have deep roots (I'm not familiar with Ficus roots), but probably the spreading roots are near the surface.

Then put in a blocker. Vinyl flashing might be adequate; you can get

24" wide for about $1.20/ft at HD, probably less in bulk. Or use the narrowest ditcher you can, and fill the trench with concrete, but I'm sure that'll cost a lot more than flashing.

This page

sort of implies that Ficus roots are shallow, maybe even only 12" deep. I also found comments somewhere that Ficus produces shallow roots in AZ because of lawn watering that leaves the surface damp with no water below, implying that avoiding lawns and using only drip watering if it's necessary at all might reduce the root problems.

I found a long and very interesting thread about Ficus in AZ at

That thread is five years old but I'll bet a lot of the same posters are still around.

As to whether it's a water waster, I found differing opinions on how much water Ficus uses. In any case, one has to balance the water use with how much it lowers the cost of cooling buildings. Of course in southern AZ one can use swamp coolers.

I have some great recommendations for shade trees ... for Florida. The ones I like won't grow in AZ.

Edward

[Higgs Boson]

Ask on a NG that deals w/such problems. Use keywords like "trimming trees" or "trim tree roots",for example. Or NGs like -- pretty quiet this time of year.