Yet another screen hedge is being attacked by a foreign pest. First it was the Syzygium aka Eugenia attacked by a foreign psyllid in the late 80’s, now it is the Myoporum. Our stores have seen a number of samples this week and suggested we let you all know about it.
The new pest is Klambothrips myopori, a recently discovered thrip species from Australia that was first detected in San Diego County in 2006. It has successfully traveled north along the coast and was first detected in the San Francisco Bay Area in June 2008. Both the Myoporum laetum ‘ Carsonii’ and the Prostrate Myoporum are affected. Thrips distort foliage on terminal shoots causing the leaves to swell, curl, develop galls and ultimately blacken. Eventually, the plants may defoliate and die if the insects are not controlled.
The minute pirate bug and assassin beetles have been seen predating the thrips but are not able to completely control the pest. Sprays are necessary in the interim as new research is underway to locate an effective biological control. Spinosad (organic), and the Bayer Advanced Tree & Shrub (also known as Merit) have proven to be effective in eradicating the thrip. It has also been seen that the Myoporum laetum ‘Compacta’ and Myoporum ‘Putah Creek’ are showing resistance to the thrip.