infected euonymous emerald n' gold

[birdwoman]

I have a 4-year-old set of euonymous shrubs that I use as a hedge. All five have been thriving well. In the past month, however, something has been infecting them. The undersides and topsides of leaves and all the bark is becoming covered with hundreds of tiny, white, extremely narrow bugs(?). They do not appear to be flying insects, nor worm-like creatures. Leaves are now falling off by the dozens. Perhaps it is a fungus, but the things are very distinct. They look like tiny fingernail clippings, although completely straight, about 1/8 inch long. The infection started at one edge of the hedge and is now spreading down the row. I have looked at pictures of garden pests and diseases but so far have found nothing that parallels what I am seeing. Any ideas?

[grandpasrose]

Your shrubs sound like they have something that is called Euonymus scale.
Euonymus scale females have dark brown to gray, pear-shaped bodies. The white coverings of males are smaller and narrower. These scales can completely encrust twigs and leaves of Euonymus. They use their piercing- sucking mouthparts to feed on sap. Infested plants grow very slowly, if at all, and yellow spots may appear on the foliage and foliage drop. Heavy infestations can cause branch dieback and may even kill some plants.

This is a particularly vigorous pest, and will take diligence to get rid of. First clean up all the dead and fallen material and destroy it (do not put it in your compost). Then prune back any affected areas remaining on the plants, and also destroy what you have cut off.

Once you have done this, treat the shrubs with neem oil or insecticidal soap. Because their cycle is so quick you will need to do several applications, and I probably would alternate the two.

Also this scale seems to prey on plants that are stressed in some way. So make sure that you have given your shrubs nice fertile soil (add compost, fish emulsion, kelp, leafmold, etc.) and ensure that they get enough water.

When new growth appears on your shrubs, you should protect it from the scale with either a dormant oil, or neem oil spray to prevent the scale from taking hold on new growth.

I hope this helps and you are able to save your shrubs! Good Luck and let us know what happens!
VAL

[The Helpful Gardener]

These plants are a magnet for this type of scale, and the soap won't really do it; need the oil here and neem works better than most. Treat now (avoiding hot sunny days; oil will burn plants) and then again in fall. Examine again in spring, and treat as necessary.

Or haul 'em out and plant something that won't get attacked regularly

Scott