Spruce down, tells a story

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Toppling is a problem for Colorado spruces (Picea pungens). They are dense, so they take on a lot of weight in water, ice or snow. They take wind full on, like a sail. Most landscape spruces also have underdeveloped root systems. Improve the root system to keep your spruce upright. 

Wide roots most stable

After a windstorm we can learn about tree root systems -- bad root systems, especially.

A tree that stands up to wind does so by virtue of wide roots. The same physics apply that make us steadier when we take a wide stance.

Most tree roots are not particularly stiff -- some species' roots have historic uses as rope and bindings because they're so flexible. So their wide base isn't stiff like the foot of a goblet. It has the flex of our knees. The top can rock in the wind without snapping roots.


Grass and water to blame

This spruce's root system should have been about 18 inches deep, with 4 - 11 large diameter flare roots, each ranging as wide as the tree is tall and giving rise to many branching roots along the way.

Instead, it was shallow and restricted, unable to win against grass and poor drainage.


Competition slows root growth, especially when the tree species involved is one that never had to develop ways to co-exist with a greedy, chemically off-putting groundcover like Kentucky bluegrass. Roots stall, too, where oxygen's been displaced by water. Here, the soil is so compacted that water's still puddled just below ground 30 hours after a storm.

There's a large root, its broken end just above the pointing shoe. It's one of only two of that size we found at this root system's perimeter. With just two flare roots spread wide, the tree had no chance once its top became large and the wind strong.



Keep your spruce standing tall

Write a different story for your spruce so you'll never see its roots. At planting, create a well-drained, grass-free ring at least a few feet wider than the tree's widest branch tips, and expand it as the tree grows. Keep the soil aerated within its rightful root zone -- a circle as wide across as the tree is tall. You tree will be more stable and also resist its other pests.