Friday, February 22, 2008

Landscape - Precautions in Using Guy Wires and Stakes

Staking and use of guy wires may be necessary in sites exposed to heavy winds. However, they should be used with caution so you don't harm the tree. The following are some points to consider on the subject from the University of Massachusetts.

Staking is a technique used to protect, anchor, and support recently transplanted trees. The following are some questions and answers on staking.

Do I need to stake trees?

Not usually. Most young trees can stand unsupported, and will be stronger without stakes. Staking actually delays the creation of a strong tree. Trunk movement signals the lower trunk and roots to produce increased growth. A better trunk taper and root system results. Research shows that bare-root trees can stand unstaked as well as B&B or containerized ones.

When is staking recommended?

There are certain situations where staking can be advisable:

>very large tree size
>fall-planted evergreens
>high wind conditions
>very weak trunk
>high population pressure

What are the potential drawbacks of staking?

>Poor trunk development at the base of the tree.
>Increased trunk caliper near the support ties, which produces a negative trunk taper and restricts the vascular tissue conducting water, nutrients, and sugars.
>Wounding or girdling from ties too tight against the trunk, especially when they are left on too long. Concentrated pressure from narrow ties (e.g. elastic webbing, wire, or even wire through a hose) will crush or cut through the bark.
>More wind throw and wind damage later, particularly when the tree is staked rigidly. Most susceptible are shallow-rooted evergreens and trees with a large "sail."

What are the current recommendations?

>Don’t stake if you don’t have to.
>Consider alternative methods of staking.
>Remove stakes and ties within 1 year, or use degradable materials.
>Use flexible ties with a broad, smooth surface.
>If vandalism is a consideration: instead of staking, try planting larger caliper trees, or encircling the tree with heavy posts, wire, or metal grill work.
>If protecting from mowers and foot traffic: sink three 4' stakes halfway into the ground, 15" or so from the tree, and run a line between them to make a triangle.
>If follow-up maintenance within 1 year is unlikely: use 2" x 2" pine stakes, and UV degradable ties. The stakes and ties will fall off by themselves.
>If staking because the trunk is too weak: place the ties 6" above the lowest point where, when you hold the trunk, the top will still return upright after being bent to the side.

Reprinted from Staking Trees, a University of Massachusetts Cooperative Extension Factsheet.

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