Recently we were contacted through our website by a member of the public to identify a mysterious bug:
"There's a bug that lives on the top leaves of my rhododendron in the summer here in White Rock.
It is about 1/2" long , 1/8" thick, green colour with red stripes front to back, it can fly, it sprays clear sticky liquid from its rear end, and faces the middle of the plant, would be happy to send a picture of one , if that helps..."
We requested the offered photos, and after a quick Google search of images matching the photo, and by using the key words: 'green with red striped bug in BC' we found the answer as: Rhododendron leafhopper a 'sucking' insect partial to Rhododendrons and many other herbaceous plants. Note Red Banded or Candy Striped leafhoppers are similar but only G. fennahi is found on the Pacific Coast.
The adults and nymphs may attack plants by feeding on the foliage, but they do not cause serious harm. (There is some thought that leafhopper may contribute to spread of bud blast as female leafhoppers make slits in next year's flower buds. ) Avoid over fertilizing with nitrogen which promotes lush green growth that in turn attracts leafhoppers and other pests such as aphids. This Red Banded Leafhopper secretes a 'honeydew' substance, which contains a lot of sugar, often causing ants to care for them as they do aphids. Sunset Western Garden Problem Solver suggests control may be had by spraying the affected leaves with a strong blast of water from a hose. Natural predators include birds, beneficial Green Lacewing larvae, and parasitoid wasps.