Thursday, November 29, 2007
Expect mixed results for transplanting old oak trees
John Arbogast
Landscape consultant John Arbogast answers your questions every Thursday. Send questions about your lawn, garden, plants, or insects to:
Dear John
5102 Greenfield St. SW
Roanoke, Va. 24018
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Q: I am curious if adult oaks can be transplanted? The oaks that I’m thinking about are more than 60 years old.
A: In our clay soils here in western Virginia, I don’t think that oaks that are more than 60 years old can be moved successfully unless they have been “root pruned” annually during their lifetime. Oaks have deep root systems and are known for their taproots. Root pruning is done by commercial landscape tree growers to force a subject plant to grow a dense network of relatively short roots so that the plant will have a dense, moveable-size, root ball that can be dug in a later year.
Even here, though, I suppose that attempts could be made to transplant oaks in their 60s using the biggest hydraulic tree spade if the oaks have historic or personal significance. In case you aren’t familiar with this type of machine, a hydraulic tree spade is an apparatus that uses a ring of steel digging prongs that are forced into the soil surrounding a tree to eventually separate a “root ball” of tree roots with their soil and then lift this mass out of that ground. I believe that operation of a hydraulic tree spade is expensive and time consuming. Success is not guaranteed.
Wherever the oaks are as long as they are in clay soil and money, time, and commitment to adequate post-planting tree care are not a problem, transplanting time-of-year will still be critical. The best time-of-year will be when the trees are dormant plus when the soil is warm enough for quick root recovery. Here in western Virginia, those 2 conditions come together in mid fall and in late winter or early spring. Even though climate change is making the growing season longer, the fall transplanting time is not lasting longer accordingly. Roots in new soil that remains warm longer remain tender longer as well.
If the 60 plus years old oaks you’re asking about moving are growing in sandy soil, I’d be skeptical about transplanting, even with a powerful hydraulic tree spade. I don’t know how an adequate root ball could be formed with sandy soil.
Q: I heard about a plant called Tickle Me Plant and plant growing materials on this. I would like to know if you’ve heard about this plant and where I can order or get supplies for it. I teach a group of youngsters in my church and thought that the Tickle Me Plant sounds like something that they would be interested in.
A: I haven’t dealt with this plant, but I have read about a TickleMe Plant Company that offers educational plant products and activities. Try doing a search on the Web for “Tickle Me Plants”. I haven’t used that company, so I can’t vouch for their stuff.
I have heard about and touched a small plant called “Sensitive Plant”. This little plant is a type of Mimosa that is related to the Mimosa trees (botanic genus name is Albizia) that grow here in Virginia. “Sensitive Plant” has compound leaves composed of many little leaflets situated along a long central stalk. The leaflets fold inward when the leaf is touched.
Q: My Christmas cactus always blooms early. Right now in late November, its blooms are drying up and falling off. I keep this Christmas cactus outside on my porch for the summer and bring it in to a sunny window early each fall. What am I doing wrong? None of my friends seem to know.
A: I think that the only thing that you’re doing wrong is naming your plant. It sounds like you have what is commonly called a “Thanksgiving cactus”. That plant looks similar to the Christmas one, but it does bloom earlier.
Q: In early fall, I saw some blooms on my azaleas. What’s happening? I live in Virginia.
A: Blame the wrong-season blooms on Mother Nature. You’re not doing anything wrong.
Azaleas are known to produce some blooms in early fall following a stressful summer if rain comes in late summer when the nighttime temperatures begin to cool down a few degrees. No care jobs are required.
