Q. We plant sweet potatoes in a raised bed the length of our garden. We have had an animal go underground and eat one-third of it. This year, some grew 10 inches long and 8 inches around. I’ve read that an animal–“a vole”–could be the problem. What can we do about it?
A. There are several species of voles (field mice). Voles are active day and night, year-round. Their territory is usually one-fourth acre or less but varies with season, population density, habitat, food supply and other factors. Voles construct many tunnels and surface runways with numerous burrow entrances. Voles eat crops and also damage them when they build extensive runway and tunnel systems. Runways are 1 to 2 inches wide and the vegetation may be clipped close to the ground. Feces and small pieces of vegetation are found in the runways. Other animals such as ground hogs could be the culprits, but, in the end, the strategies to reduce damage are about the same.
Good garden sanitation can help reduce the likelihood and severity of vole damage. Eliminate weeds, ground cover and plant litter in and around the garden. Small garden areas could be protected by placing one-fourth-inch metal mesh hardware cloth cylinders around the planting. Bury the mesh at least 6 inches deep to keep voles from burrowing under the cylinder. And, finally, a good garden cat might help!
Q. I had a 3-year-old Colorado spruce tree, and it did well until this past summer. The needles were eaten off gradually by something I couldn’t see. I finally dug it up. I also have a pretty blue spruce that is nearly 2 years old. Is there anything I can spray on it to keep it healthy?
A. There are several insect pest possibilities, including but not limited to bagworms, sawflies and scale insects. Since blue spruce is a selected cultivar of Colorado spruce, they would be likely to share pests in common. But, unfortunately, it is not possible to identify the culprit without more info about symptoms and signs of feeding damage. Control recommendations, be it a “spray” or other method, can only be appropriately suggested after first identifying the cause.
Keep a close eye on the blue spruce so that if an insect or other problem should arise, you can bring in a sample to the Purdue Extension office in your county for assistance in identifying the culprit. And, in the meantime, you might read up on Purdue’s publication on bagworms to see if that looks like what happened to your Colorado spruce http://www.entm.purdue.edu/Entomology/ext/targets/e-series/EseriesPDF/E-27.pdf.