Ask the ISU Extension Gardening Experts

My neighbor’s ‘Tiger Eyes’ sumac has produced several suckers.  Can I dig up one of the suckers and plant it in my yard? 

Suckering (the production of shoots from the plant's roots) is a very distinctive characteristic of sumac (Rhus species). Sometimes the suckers are annoying as they pop up in areas where they're not wanted. 

It is possible to dig up and transplant suckers.  Early spring (while the shoot is still leafless) would be the best time to dig up a sucker.  Replant immediately.  Keep the plant well watered.  There’s a good chance that the transplanted sucker will survive. 

What is the common name of the tree that produces yellow-green hedge balls?

Hedge balls or hedge apples are produced by the Osage orange (Maclura pomifera). Other common plant names include hedge apple, bodark, bois d'arc and bowwood.

The Osage orange is a small- to medium-sized tree. It commonly grows 30 to 40 feet tall, occasionally as tall as 50 to 60 feet. It typically has a short trunk and a rounded or irregular crown. The leaves of the Osage orange are a shiny medium to dark green. They turn yellow in the fall. The twigs are buff to orange-brown and are armed with ½ -inch long spines. The stems exude a milky sap when cut. The Osage orange is dioecious. Male and female flowers are produced on separate trees. The small, green flowers appear in May or June. The female trees produce 3- to 5- inch-diameter fruit. The fruit somewhat resemble a yellow-green orange.  Mature fruit fall to the ground in September or October. 

The wood of the Osage orange is golden yellow or bright orange when first cut, but turns brown on exposure. The wood is extremely hard, heavy, tough, and durable. It also shrinks or swells very little compared to the wood of other trees. The wood is used for fence posts, insulator pins, treenails, furniture and archery bows. In fact, many archers consider the wood of the Osage orange to be the world's finest wood for bows. (The name bodark is from the French bois d'arc meaning "bow wood.")

The common name of Osage orange is derived from the Osage Indians (who used the wood to make bows and other tools) and the fruit’s resemblance to a yellow-green orange. 

My ‘Sunburst’ locust is not growing well.  What could be the problem? 

The ‘Sunburst’ honeylocust has distinctive yellow-green foliage.  Unfortunately, it is not a vigorous grower.  It grows slowly and is susceptible to cankers and mimosa webworms.

Cankers, caused by fungal pathogens, are localized dead areas on branches, twigs and the trunks of trees.  The most common canker on honeylocust is Thyronectria canker.  It typically attacks trees weakened by adverse environmental conditions or poor care.  Thyronectria cankers are usually elongated and slightly sunken when young, with callus ridges at the edges.  Initially, the surface of the destroyed bark is frequently orange-brown.  It later bleaches to bright yellow-orange.  Fungal cankers cannot be controlled with fungicides. The best way to prevent cankers from attacking trees is to keep the trees in good health with proper care. 

Mimosa webworms are grayish brown caterpillars.  Damage occurs when the caterpillars tie the honeylocust leaflets together and feed on the foliage inside the protective webs. Damaged areas eventually turn brown.  There are two generations per year.  If necessary, mimosa webworms can be controlled with insecticides.  Insecticides must be applied shortly after egg hatch (typically mid-June and early August in Iowa) and before webbing is apparent. 

For more gardening information visit us at Yard and Garden Online.

Contacts :
Richard Jauron, Horticulture, (515) 294-1871,