Picea pungens wind throw

Over the years I've noticed this species seems very susceptible to wind throw, with trees in the 15'-20' range most vulnerable. Outward appearances would indicate they're healthy. While most of the trees I've seen down are highway plantings in the Twin Cities metro, these pics are from a commercial planting in Brainerd, MN. This is a group of four, with three laid down in a storm from last week. Only one at the opposite end from direction of wind stayed upright. I'm guessing they were B & B stock, but not certain of that. Does this species broad and dense growth habit increase the liklihood of wind throw, especially at this stage of development, or is it more of a root problem?

All that plastic in the soil certainly won't help.

Resin

Do you have more information about the genesis of this planting? Brand new? 20 years in the ground from a 6' transplant? I see staking in the last image - was that brand new, or has that been a component of the entire planting all along? Did these go down after staking was recently removed?

Agree with Resin - the inorganic layer that only allows some water/gaseous exchange is not a positive factor in establishment of a strong root system.

Considering this species hails from the benign calm sedate windless region of the Rocky Mountains...

I do not know the planting particulars. However, I do know the staking you see on this one tree was done following the storm. I spoke with the property/business owner who said they had a tree service stand it up and stake it, but it then had to be restaked, which had been done in the past couple of days.

What I find interesting is how many Colorado Spruce I've seen over the past ten years or so that are taken down by moderately strong winds. I'm not talking 80-100mph gales, but rather in the 40-60mph range. I did not see any other trees down in town...or downtown.

I think your last statement, John, is interesting and a reasonable explanation for this phenomenon. Is it also possible that planting this species in a relatively isolated and/or exposed site, combined with their habit & cultural preference, could explain their wind throw vulnerability?

I guess I need to be more blatant when making sarcastic remarks.

Picea pungens is a western North America native (Rocky Mountains range) - where there will be no shortage of winds and snow loads for Colorado Spruce to endure. I don't think this species has any more or less resistance to wind when planted singly or in small groups (versus as a forest member) than any other tree species that would occur as a forest member.

I think windthrow is more directly linked to poor attachment via the tree's roots. If there aren't very many roots growing firmly into the surrounding soil to anchor the tree, then physics wins every time. A vertical object that provides a large surface against which wind can act, will experience a loading against that surface which will move it in the direction of loading (which way the wind blows). If there is no good footing supporting that vertical object (be it tree, flagpole, wall, person), then it will move in the direction of the loading (windthrow).

There are other things that can cause this sort of failure, even when rooting is pretty good. Excess moisture in the soil profile can reduce the solidity of the roots' connections, and roots can be pulled out during heavy wind loads. I haven't had lots of experience with high percentage sandy soils, but that may present an equivalent issue.

I would lean toward inadequate rooting volume, density, and spread/extent. This will be exacerbated as the size of the transplanted tree increases - more head, less roots relative - because the bigger tree will take longer to regrow and re-establish sufficient roots to support it against these adverse conditions.

Since you are seeing these failures in urban/development sites - rather than on pastoral farmland situations - I'm betting the soil zone conditions and adaptability (or not) of the spruce to exploit the soils extensively and quickly enough is the "root" of the problems observed.

I can only offer this opinion from a 12-14 hour drive/800 mile distance.

The problem is NOT the Colorado Spruce, IMNTBHO.

The problem is (likely) site conditions not properly prepared to grow such a tree. I can't presume that "...other trees of similar size & age, and growing under similar conditions..." actually are experiencing the same conditions since you explicitly stated that you have no knowledge of the planting particulars. There might be trees that won't blow down when planted on a sidewalk (Ailanthus comes to mind), but does that make Colorado Spruce the villain?

If a 8-10' B&B Colorado Spruce is transplanted to a heavily compacted clay soil bathtub-like planting hole, fails to produce vigorous establishment roots, and then blows over as a butterfly flits by, does that make Colorado Spruce the villain?

If a landscape contractor procures a cut-rate priced large conifer with an undersized rootball for its caliper/height/age, does a shoddy installation job with minimal planting hole prep and wedges it into the undersized hole about six inches too deep and stomps the backfill soil down so it can't move during the "warranty period", which subsequently blows over when Pseudo drives by in a hurry - does that make the Colorado Spruce the villain?

But I digress - except from the sarcasm part.

Focusing on the species of tree is a straw man, easy to knock down without performing a little more (albeit more difficult) analysis. Compare to the summation "It just died" when describing a loss of a tree.

All right - waited long enough for a reply.

Doesn't the size of the intact soil ball on that prostrate tree ring some pretty big bells in participants here - given the size of the plant?

I have an advantage, this being my professional career since 1984, and I automatically assess things to a bit greater degree than the average gardener. Guilty as charged.

There has been a recession since about 2006-2007, since which time nurserymen have watched their field stock get bigger and their client list and sales get smaller. When someone does show up and wish to buy a plant, the gleeful plant producer will sell them the biggest thing that the buyer will take. And not necessarily to any ASTM/AAN/ANLA or other standard, but for a good price.

Many many many large plants have been distributed in the past few years in just this manner. Landscapes everywhere stand to look impressive in the short term, but not necessarily perform as expected in the long term. Blowdowns are probably a blessing compared to some other catastrophic potential results.

Short-changing the rootball from the correct size for the height/caliper of a tree is far from unknown in the industry, and there are far too many vendors and contractors willing to look the other way - and expect that the client knows nothing, sees nothing, and perceives that they just got the deal of the century.

Goodness, how you do go on. I'm certainly not tyring to make "Colorado Spruce the villain." That would be anthropomorphic, and you know how I feel about that. I've merely made an observation over a long period of time that this species is unusually vulnerable to wind throw at a certain size of development. You have gone to great lengths trying to explain the likely cause as being such things as poor root attachment and undersized root balls. I'll simply state once again that Picea pungens IS NOT the only tree that is (1) subject to poor horticultural practices, and (2) commonly used in commercial plantings. I don't see other trees toppling over at anywhere near the rate that these do. Why is that?

Try to peer through your Cheese Haze, and discern the questions I've asked that you have NOT answered.

Therein will lie the truth, Grasshopper...

Sensei, thank you for your patience and imparting your vast wisdom on this lowly gardener. Sometimes the most simple of questions are the most difficult to answer.

Lol...thanks for the info + entertainment.

Just an amateur chiming in here. I have grown a pair of Picea pungens AKA Colorado blue spruce, and several solidary trees up high on a windswept hill. The soil is very sandy. Every house in my neighborhood has one too. You see, twenty five years ago, we tied Jordan almonds on one year old seedlings and gave them out as wedding favors, and what our guests didn't take, the rest of the neighborhood got. Now there are about 200 of these seedlings/trees that various people have occasionally shown me or sent pictures. Not one of them has been blown over by the wind, even though there is a great deal of variation in their growth or beauty. Since my property has ledge, I have also observed that the roots adapt very well to that too.

So my conclusion is that those trees did not have a sufficient rootball for their size and perhaps other problems with their culture. Commercial property owners want instant gratification, just as the nursery industry caters to it. Don't have to be an insider to see that.

Of course VV makes the explanation more entertaining.

Yes, quite the entertaining bunch you are! Very good info. I thought it was obvious the root ball was of insufficient size given the tree height. One thing I will say about this tree and others like it, you can't really get away with cheaping out on the roots because, with their dense branch structure, it's asking for trouble. We have one in our yard about 35' and it's a solid tree and takes abuse. Perhaps these trees are just a little less tolerant of poor landscaping practices and transplant procedures.

I've always heard them called solidary trees. Perhaps it's because the roots don't accept a lot of abuse. When we put in a horse fence for our giant dog, two of our nearby ones got pretty sickly and only one fully recovered.