A sample of blackberry cane was submitted. The cane was lumpy and deformed but otherwise alive. Only one cane was affected.Closer inspection revealed that the lumps were actually ridged areas around the cane. Opening the cane up showed evidence of an insect larva tunneling (boring) through the interior of the cane just below the bark. Damage like this is common to boring insects. If the damage completely girdles the cane, branch or stem, everything above that point will die. In this case, the large width of the blackberry cane was more than this borer could chew through. Since only one branch was infested and removed for sampling no further action was needed. If more branches were infested, they should be removed and destroyed before the adult borer emerges in the spring.

Though no borer was found, one probable culprit is the Red-Necked Cane Borer, Agrilus ruficollis. This borer emerges in May to lay eggs on new stems and the larva creates spiral tunnels which result in formation of a gall by August. The larva overwinters and emerges in May.

More information can be found at: http://www.ento.vt.edu/Fruitfiles/redneck.html

Above: Close up of damage; the tunnel is packed with insect waste, called frass. this created the dark brown tunnel in the lighter brown pith.

Above: Stem cut in half to reveal borer damage. The borer tunnels into the pith (the brown center) to spend the winter.

A client had called in with concerns about declining turf in the backyard. Large areas of a well-cared-for lawn had been declining for several years. This year the problem progressed into dying patches of turf. In order to diagnose properly, a sample was submitted to our in-house diagnostic clinic. The sample (shown at right) was a good size (about five inches on all sides) and was in good condition.

There were no insect or disease problems apparent in the sample that would have caused the decline described by the client. However, the sample had a very heavy thatch layer of over one inch thick (shown at right) which was common accross the declining are of the lawn. Thatch is an area of partially decomposed turf stems (rhizomes) at the surface of the soil. Accumulations of thatch brought about by rapid turf development (not grass clippings) can inhibit fertilizer and water penetration to the roots of the grass--turf decline is the ultimate result. The client did not want to replant the entire area but was willing to try core aeration to reduce the problem. More information can be found at:
http://ohioline.osu.edu/hyg-fact/4000/4008.html