By Curtis Utley, CSU Extension Agent, Jefferson County
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| Upright junipers. The center specimen has a co-dominant leader |
Upright or fastigate evergreens are a common and attractive
feature of many home landscapes often used as screen plantings or focal points
in narrow planting beds. However, In Colorado, or any community frankly that
experiences heavy snow fall in the winter, these narrow specimens can be
damaged, disfigured or down-right destroyed by heavy snows. Why does this occur?
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| Snow-load impacted Arborvitaes |
Narrow tree forms
succumb to snow load breakage because the side branches are poorly attached.
The strongest branch attachment forms a 90 degree angle between branch and
trunk (think of any native spruce or fir). When branches are attached more
acutely there is
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| Right-angle branching |
less trunk material to hold the branch into its socket. The likelihood
of included bark forming between the trunk and a branch increases if a branch immediately
ascends from the tree’s trunk. The other reason Fastigate cultivars often break
in snow load events is our fault in how the trees are pruned and managed. Most
narrow cultivars are sheared to keep their appearance balanced and tidy. If the
terminal branchlette is clipped and apical dominance is removed, aggressive,
competing side branches will try to grow up and become the leader.
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| Strong central leader |
If these
competing side branches are maintained they will grow into co-dominate leaders
that will have included bark in the future and may break in future snowstorms.
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| Co-dominant leaders failing after heavy snow load |
So what should you do to protect your fastigate trees in the
winter?
Wrap them with Ag fleece.
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| Ag Fleece protects shrubs from snow-load and desiccation |
1. Wrap them with straps
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| Wide strap wrapped around a Woodward juniper |
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| Light cord or Christmas lights can prevent snow load breakage |
2. Wrap them with Christmas lights or light cord
3. Stake them when small and tie them loosely to the stakes
Hmmm, wrapping with seasonal lights is a very playful solution!
ReplyDeleteI wrap mine with bird netting. Allows for breathability, sunlight and also moisture.
ReplyDelete