Root girdling can cause demise of sugar maple

Dear Jane: We have a large sugar maple tree in the front yard, and it's in full color. For the past few years, it has tended to turn yellowish-orange earlier than other trees in the neighborhood, but it has completely turned now. A few branches also have died in the top. What would cause this?

-- B. Petersen, Upper Arlington

Dear B.: Premature fall color can be a symptom of a girdling root at the trunk base. A girdling root can grow just above or below the soil surface, encircling the tree's trunk and slowly restricting the movement of water and nutrients. Although girdling roots don't kill a tree, they contribute to decline and premature death.

Through time, growth slows; leaves become fewer, smaller, lighter green or scorched; twig growth is reduced; and, eventually, branches begin to die back.

Girdling roots are thought to be the result of conditions that keep roots from growing in a spreading manner. An example is a tree kept in a container in which the roots have been forced to grow in a circular pattern. If the roots aren't pruned or straightened at planting, the growth pattern will continue and can lead to girdling roots.

Other causes include planting too deeply; failing to remove a wire basket from the root ball at planting; and mulching plants too deeply.

Ask a certified arborist to examine the tree for girdling roots or other potential problems.

Dear Jane: Squash bugs killed my squash vines this summer. I salvaged a few butternut varieties and wonder whether they will ripen and whether I can use them.

-- Mary Lou Brown, Granville

Dear Mary Lou: Typically, winter squashes are left to ripen on the vines into late September or early October. They won't ripen well off the vine. But some gardeners harvest a few squashes before they're fully mature and use them right away.

Because you've already lost vines, go ahead and cut the squashes and see whether they're usable now.

Dear Jane: I came across a plant in a public garden, but it wasn't labeled. It's blooming now. It's somewhat shrublike, about 3 feet tall, with maplelike leaves and yellow bell-shaped droopy flowers. Would you have any idea what this plant might be?

-- Lucy Miller, New Albany

Dear Lucy: The plant might be yellow waxbell (Kirengeshoma palmata), which should be used more in gardens for its late-blooming qualities.

The herbaceous perennial is shrublike in size. It grows best in woodland settings in partial shade and with abundant organic matter in the soil.

The flowers rise a bit above the foliage, are a soft yellow and nodding.

Send questions to Jane Martin, Growing Concerns, The Dispatch, 34 S. 3rd St., Columbus, Ohio 43215. Include full name and address; names and hometowns are published.