My Benjamin Britten, a David Austin Rose has a problem! Some, and only some canes are producing miniaturized yellow leaves with a red rim. I have examined the canes (no insect damage) and the leaves and buds themselves. I can see nothing.Other canes on the same plant are producing perfectly normal leaves. However, some of the canes on the neihbouring Teasing Georgia are also affected. What to do? Dig and discard or????
If not a virus infestation due to the plant being produced using unclean stock maybe it has picked up something since being brought to your site. Back east they are moaning about hypervirulent rose rosette, if this also becomes widespread out here it won't be a picnic for us either. Any herbicides been used near your plant? Widely used glyphosate, for instance seems to be murder on roses, producing discolored and deformed growth that may perhaps be quite similar to rose rosette in appearance. You seem to be describing something different but probably other herbicides produce different effects. With glyphosate anyway it seems all your roses have to do is hear you talking about using it and they are adversely affected.
Does the damage from glyphosfate persist for more than one year? Is rose rosette the condition that produces a mad bud and leaves all condensed together? How do I diagnose for a virus? Thanks for your suggestions. Lovejoy
I hope it isn't rose rosette disease (RRD). Because it will spell bad news not just for you but for the rest of rose growers in south western BC. By all accounts, RRD is not prevalent in the Pacific Northwest. Rose rosette disease is caused by a virus which is transmitted by the eriophyid mite, P. fructiphilus - a windborne mite. RRD was originally used as a potential agent in the control of Rosa multiflora infestation. It was originally transmitted to target multiflora roses by grafting and by mite releases in Iowa and West Virginia. As one can well imagined, the use of RRD has been vehemently opposed by the American Rose Society. Increasing reports of devastating damage to ornamental roses has been reported - as shown in this map. The signs of infection tend to vary depending on the variety of rose infected. Some of the more easily recognized signs include 1. rapid elongation of new shoots 2. development of witches' brooms or bizarre clustering of small branches 3. the leaves in the witches' broom are small, distorted, and and are often reddish in color. 4. excessive growth of exceptionally soft and pliable unusually coloured thorns on canes is diagnostic. These stems are often thicker than expected, and may be thicher than the older cane that it arises from (although, in my experience, this may also be part of normal growth) 5. flowers may be distorted and bizarre shaped and bear no resemblance to what one would expect for the variety of rose affected. The bad news is that there is no cure, and the rose usually dies within a year or two. The even worse news is that it spreads quickly to other surrounding roses. Pictures of RRD
