Threatening Cereal Beetle Found In Region

Dr. Jan Knodel, NDSU Extension Entomologist, recently reported finding a relatively uncommon insect, cereal leaf beetle, feeding on barley and winter wheat in three new countries of North Dakota. These insects were found at the North Dakota Research Extension Center at Minot, in Burke County near Flaxton, and in Renville County near Mohall.

Adults and larvae both feed on the leaves of cereal crops with the larvae being responsible for a majority of the damage which looks like elongated windowpanes on the upper leaf surfaces. The good thing so far is that the population levels at the three locations were very low and expected to have no economic impact on crop yields. Also, most of our cereal crops are now beyond critical crop stages – pre boot and boot. If the insect is present before the boot stage the economic threshold is three eggs and/or larvae or more per plant. All the tillers should be included in the observation before the emergence of the flag leaf. Larvae feeding in early growth stages can have a general impact on plant vigor. When the flag emerges, feeding is generally restricted to this leaf which can significantly impact grain yield and quality. If the crop is in the boot stage, one larva or more is considered to have potential to cause economic losses.

The mature cereal leaf beetle has the appearance of metallic blue-black with orange middle. The legs and prothorax are red. The females reach .25 inch in length and are slightly larger than the males. The larva has a pale yellow body with a dark brown head and legs. The larvae eat narrow strips of tissue from between the leaf veins. Fortunately there is only one generation per year.

This beetle was accidentally introduced into the United States in Michigan in 1962 from Europe. Since then it has spread in all directions of the United States. The beetle was first detected in Williams and McKenzie counties about 10-15 years ago.

Sapsuckers Like Sugar

A couple weeks ago I voiced a little displeasure about the mowing height of our front lawn. Apparently members of my household took the comments personal and conveniently forgot how to start the new mower or simply thought it was my turn to give the lush grass a fresh trim.

Last week, as I was following the self-propelled beast around the only tree in the yard, a flowering crab, I noticed the tree had a bunch of small ¼ inch holes that seemed to be accurately measured and drilled by a human. Over the years I have encountered other people who had the same issue so I knew who the culprit was – very likely a yellow bellied sapsucker which is a member of the woodpecker family.

Recently a Tioga businessman called to report several of his large pine trees are dead or on their way to someone’s fireplace. So, on my way back from the State Fair yesterday I stopped to inspect the trees. Once again I found these same sized holes placed in neat multiple rows often parallel to one another.

Sapsuckers like the sugar in the sap of certain trees. Once the birds find a favorite tree, they visit it many times per day and feed on it year after year. The holes are deep enough to sever the layer under the bark which is responsible for the conveyance of water and energy throughout the tree. With enough holes, this entire layer of the tree can cut off all nutrients necessary to keep the tree alive.

It is difficult to prevent sapsucker damage to trees. Wrapping the damaged trunk with burlap or smearing a sticky material above and below the holes may inhibit new pecking damage.

A close inspection of my tree did not show new holes so maybe the culprit has met his destiny or found a sweeter tree. Regardless, I will be watchful should he or his relatives come to visit again.