Plucking out wire supports from tree bark can be tricky

Q: A tree at our new home has wire stuck into the trunk where it was once cabled up, years ago. Should I remove this? The tree bulges out over the wire.

A: As a general practice, trees that are staked should have all cabling removed after one year of growth. Research has shown that trees survive and thrive better if they are allowed to move freely with winds, so current theory suggests doing as little cabling as possible. Staking is necessary if the root system of the tree is so limited that it doesn't support the tree.

When staking a newly planted tree, wrap the tying material in a length of sponge insulation or rubber piping to prevent it from cutting into the bark. Ideal tree-staking material is smooth, with elasticity that minimizes rubbing on the trunk. Elastic webbing or special poly tapes made for tree tying also work well. Use two stakes when supporting a tree to help it move and grow well. Don't tie too tightly.

Rescuing a tree that's been poorly cabled can be tricky. The cable, as it rubs against the trunk, creates a wound. Some of these cable wounds can be so serious that they cut the bark completely around the tree, in effect girdling and killing the tree. The cambium - growth - layer of the bark carries nutrients and water for the tree; slicing into that cambium can murder the plant. Check cables often, especially where they may become hidden in branches and leaves. Remove them after one year, or at the most, after two years. Adjust any cable that is rubbing against soft tree bark.

If the cable is free and easy to pull off, the tree may recover. However, you say that the tree "bulges out," and this brings up concern about how deeply embedded the wire may be. Young trees add girth quickly, and the wire, as it's covered up, will cause a circle of weak wood that breaks easily or can cause the top of the tree to grow poorly.

The difficulty is how to manage extracting wires or rope when the tree has grown over the intrusion. You might injure the tree more severely in an attempt to pry out the ingrown obstacle. Remove the wire if it lifts or pulls out rather easily. Don't dig it out, which would further wound your tree.

A tree affected by such an injury may never grow well, or may die far sooner than it would with a whole trunk.

Q: Snails have invaded my garden; why do I have snails instead of slugs?

A: You probably have both. Within the last 10 years, the introduced garden slugs have been joined by their cousins, mollusks with attitude as well as shells composed of hardened calcium. One common type here is the brown garden snail (Helix aspera), now rummaging through Northwest gardens for breakfast, lunch, dinner and snacks. Irony definitely is at work because these snails were brought to California in the 1850s as potential escargot, human food. We're now feeding them the tender parts of our garden plants.

Slug management techniques also apply to snails. Snails seek damp, protected places. They often tuck themselves against walls or stones; in my garden they lurk under rock-garden plants like candytuft where it hangs down a brick wall. Hand-picking snails is easier than hand-hunting slugs, because they obviously come with a sort of handle attached, the shell. I toss them into the middle of the street and hope the crows will find them (this would, I suppose, provide a snack called Es-car-crow).

Stomping on snails, while messy, does have a certain satisfaction!

Snails multiply and grow fast, and like slugs, can be damaging at very young ages. A baby snail has a complete shell and looks exactly like a miniature of its parents. Snails, by the way, are generally hermaphroditic, as are slugs. Each has both male and female sex organs.

If you see a concentration of tiny snails, this will help you locate the areas where snail eggs are being laid. Snail eggs look like slug eggs, white and round, resembling heaps of small pearls. Remove any eggs you see.

Our so-far mild winter may lead to early spring snail populations. Snails aren't very active when temperatures drop below 50 degrees, but they do remain alive. The brown garden snail survives in cold and dry weather by pulling into its shell, sealing the opening with mucus, and staying dormant. They've lived this way for up to four years, according to "CommonSense Pest Control," Taunton Press, 1994.

Do some checking to find out which plants in the garden attract snails. In my garden, the Gladwin iris (Iris foetidissima) fills up with small and large snails regularly. I comb them out of the plant, hoping for a complete rout, and come back in a week to more of the pests.

Snails, like slugs, will come to beer traps. Copper-strip barriers around raised beds and containers also repel snails. Ducks and geese eat snails, and I've heard reports that some dogs do, too.

Gardeners are also experimenting with success with a relatively new bait type containing iron (ferric) phosphate (sold as Sluggo or Es-Car-Go). This type of slug bait isn't toxic or lethal to dogs and cats, as are the older ones containing metaldehyde. Read and follow all label instructions on any pesticide used.

And don't rely on just one method of snail control; combine hand-picking, trapping and other methods. You'll find you can manage, though never eliminate, snails.

Gardening runs Sunday in Home/Real Estate. It is prepared by Mary Robson, area horticulture agent, Washington State University/King County Cooperative Extension.

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Gardening questions?

Have a gardening question? You can reach us 24 hours a day by dialing 206-464-8470. Questions of general interest are answered as space allows in the Practical Gardener column, which runs Sundays in Home/Real Estate.

Web sites

Check out the following two Web sites for information about gardening in Western and Eastern Washington respectively:

http://gardening.wsu.edu

http://gardening.wsu.edu/eastside/

Tape library

You also can tap into the Washington State University Cooperative Extension/King County 24-hour Dial-Extension tape library of more than 200 titles. Call 206-296-3425 for a free catalog.

Master Gardener hotlines

If you need immediate assistance call the appropriate Master Gardener hotline Monday through Friday.

-- King County, 206-296-3440, from 10 a.m. to 4 p.m.

-- Pierce County, 253-798-7170, from 9 a.m. to 3 p.m.

-- Snohomish County, 425-357-6010 from 9 a.m. to 4 p.m., Monday through Thursday; 10 a.m. to 2 p.m., Friday.