It seems like every year there is one new insect pest to worry about – usually an invasive species that has found its way here from elsewhere in the world. This time, we are concerned with a beetle; the Rose Stem Girdler, a potential pest of caneberries such as raspberries and blackberries. The March 2019 edition of Country Life in BC contained an article on this insect written by Ronda Payne.
The good news: there is no evidence the Rose Stem Girdler is actually in the Fraser Valley, although, according to the article, Tracy Heuppelsheuser of the BC Ministry of Agriculture found it in the Okanagan a few years ago. The bad news: it is probably only a matter of time. This insect pest is currently a pest found in Oregon and Washington. The fact is, despite the best efforts of regulatory agencies here and in other countries, eventually we can expect non-native species of pests of all kinds to find their way to Canadian shores. Pests that are no significant threat in their native places often become major economic issues once introduced, because their naturally-controlling predators they evolved with are not present. This was the case with Spotted Wing Drosophila, then the Marmorated Stink Bug – and now possibly the Rose Stem Girdler. Although we have no knowledge of it currently infesting our crops yet, be aware of it, just in case.
The Rose Stem Girdler adult beetle chews on leaf edges, and lays eggs on the canes. Upon hatching, the larvae will bore into the cane and then feed in a spiral pattern which is quite distinct. This forms a gall that is visible from the outside of the cane. Eventually the larvae develop into pupae above the level of the gall. In about June, the adults emerge from the pupae and the cycle comes around to the beginning again.
Report any possible sightings to the BCMA, to an Agronomist at TerraLink, or to your grower association. You may ask for assistance from our Customer Service people at either Delta (4119 – 40th Street, 604-946-8338) or Abbotsford (464 Riverside Road, 800-661-4559).