A nearby forest has mimosa trees. I realize these are not native. Should we remove them? I have been told that hummingbirds like their blossoms. In the past week, I have noticed a cluster of several growing in the woods next to our home. Is this the beginning of a local invasive tree?
-- B. T. of Belleville
The mimosa tree is also commonly known as the silk-tree (Albizia julibrissin). This tree is native to Iran to central China. Hummingbirds do frequent the flowers for nectar. This tree will produce root shoots that will form clusters. But this is all the same plant.
Often, a vascular disease grows inside the mimosa, which kills the top growth and forms a mass of suckers. There is also a webworm that is highly destructive to the mimosa. This same webworm is also destructive to honeylocust trees (Gleditsia triacanthos). It seems that this insect observes the leaf formation of trees as it lays eggs only in specimens that have a double-compound leaf. (This insect is sometimes smarter than certain students that I have taught in the course of identification and use of ornamentals.)
With these two problems infecting the mimosa, it has little chance of becoming an invasive exotic plant.
Enclosed you will find some photographs of the fall color of a tree I cannot identify. Is it native? It does not grow very high, but has a beautiful rose-red color. What is it?
-- B. T. of Belleville
The plant in the photos is Winged Euonymus or Burning Bush (Euonymus alatus). This plant is not native to the United States but originated in Northeastern Asia to central China. Most horticultural literature lists this plant as growing 9 to 10 feet in height and spread, but that's only one of the cultivars -- Compactus. Ordinarily the common burning bush can grow to 15 to 20 feet tall. This plant usually does not have the characteristics of an invasive exotic plant as the seeds require a long, cold stratification for germination. However, it can tip layer with the ends of the lower side branches touching the soil and rubbing.
What is a loess soil? I have tried to find it in many soil books but there is no mention of it in the index.
-- B.T. of Belleville
Loess soil is a wind-blown soil from river bottoms that was deposited by water erosion. This soil was blown mainly from wider areas of the Mississippi, the Missouri and the Ohio rivers. The metro-east is near one of the widest parts of the Mississippi River, from Alton to just north of Chester. On some of the bluffs you can see just the limestone, but other are covered with as much as 90 feet of loess soil. Seventy-five percent of Illinois has some loess deposits.
This soil deposit is generally classified as a silt loam and in some areas a sandy loam. Loess soils do not have a weather rock formation and horizon development as most soils do. Loess soils give rise to grass vegetation as compared to tree vegetation of other soils. As a result, there can be more erosion with digging and excavation. But this soil gave rise to better soil conditions for sports playing infields in our area. It is also a good soil for raising vegetable and flower gardens.
Do it now
BIRDS: Start feeding your feathered friends.
TOOLS: Clean garden tools for winter storage.
CHRISTMAS TREES: Remember to add equal parts lemon-lime soda to the water for cut live Christmas trees to help them be more fire proof.
Charles Giedeman is a local contributing writer. Send your gardening questions to Lifestyle Editor Pat Kuhl, Belleville News-Democrat, P.O. Box 427, 120 S. Illinois St., Belleville, IL 62222-0427.