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Friday - May 29, 2009

From: Livingston, NJ
Region: Mid-Atlantic
Topic: Non-Natives, Pruning, Trees
Title: Pruning smoketree in New Jersey
Answered by: Barbara Medford


How far from ground level do I prune a relatively young Smoke tree to get the bush effect?


This is a classic example of really needing the Latin name for a plant, because common names can be given to totally different plants in different places. We started out by looking in our Native Plant Database for "smoke tree" or "smoketree." First, we looked at  Cotinus obovatus (American smoketree), which, of course, in Texas we call a "Texas Smoketree." This tree only occurs in a few Southern and Southwestern states and is not shown in the USDA Plant Profile as appearing in New Jersey at all. Next on the natives list was Psorothamnus spinosus (smoketree), which is hardy to USDA Zones 9 to 11, common to desert washes of southern part of California, Arizona and Baja California. Spiny, nearly leafless shrub or small tree and is also known under the synonym Dalea spinosa. Scratch that one. Not only is it really not an ornamental you would be interested in raising, but it would probably freeze to death by October in New Jersey.

Since those were the only two plants known by that common name in our database, we went Googling and found Cotinus coggygria, (Smoke tree) which is native to Southern Europe and Central China, and is hardy to Zone 5 or a protected spot in Zone 4. Since a non-native is out of our range of expertise, we found this  Floridata site which can give you more complete information. As it is in the same genus, Cotinus, as the native listed above, you would probably be safe in just letting it develop naturally. It actually would take pruning to keep it from appearing bush-like. They usually develop multiple trunks, with leafing no more than 2 feet above the soil. Refer to these Images for more guidelines on how the bush grows.

Cotinus obovatus

Cotinus obovatus

Psorothamnus spinosus

Psorothamnus spinosus



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