Ok, I may have made up that last part, but the rest is basically true. Since it was first documented in Manitoba in the 1940s, Rose Rosette has spread steadily throughout North America. Microscopic eriophyid mites act as the disease’s vector, spreading the virus from plant to plant (Byrne et al., 2018). After a mite feasts on an infected rose, it hitches a ride on a gust of wind (or a careless gardener’s gloves) to find its next victim. Once infected, a rose plant will display some combination–but not necessarily all—of the following symptoms: reddening of foliage, excessive thorniness, flattening or fasciation of stems (see “devil’s tongue”), and development of bushy, broom-like masses of distorted flower buds (Windham et al., 2014). I would also add, based on my observations at Elizabeth Park, that in its early stages the foliage often bears an uncanny resemblance to frisée salad greens (though I wouldn’t recommend serving it at your next dinner party). RRV is fatal, with most plants succumbing to the disease within 3-4 years (Windham et al., 2014).
Rose Rosette Virus (RRV)
So far I’ve devoted this blog to beautiful things in the garden, such as heritage roses and trellised arches covered in rambling blossoms. Today, however, we take a turn for the ugly to discuss a particularly virulent rose disease called Rose Rosette. To this not-so-scientifically-minded gardener the Rose Rosette Virus (RRV) reads like something out of a sci-fi novel: An otherwise healthy plant contracts a mysterious, airborne illness which corrupts its RNA, causing it to mutate into a prickly, discolored mass of grotesque foliage resembling a witch’s broom. The plant then develops a taste for flesh, devouring unsuspecting small children and pets.