Damage Caused by Myoporum Thrips

Healthy Myoporum laetum

Leaf curling and galling;

damage caused by

Myoporum thrips.

Damage has been seen all over the Central Coast of California. It was found that there was minor correlation between coastal regions and thrips damage. In coastal areas (within about 1 mile of coast) damage was present, though generally less harsh than more inland. This correlation did not hold strong in Avila, CA, though, (as some plants within 200 yards of the ocean were very heavily effected). It is postulated that this is due to the protected environment and warmer, less foggy conditions (on average) that Avila exhibits that the thrips are able to flourish. It is either the colder coastal conditions, the presence of moisture or a combination of the two that is the reason that unprotected coastal areas generally see less severe Myoporum thrips damage.

It has been observed that in situations where older bushes had recently had been heavily pruned back (assuming because of thrips damage as there were plants in the nearby landscapes that had major damage) that were flourishing with unaffected to minorly effected new and semi-new growth. This appears to be good control method if one does not mind hacking back their myoporum every time they get bad thrips. It seems that younger shoots are more resistant to thrips, probably due to the hardy nature of Myoporum that has made it such an invasive weed as well as a desired landscape plant.

Also of note, it seems that there is a minor correlation in shaded plants

exhibiting less severe thrips damage than those in full sun. This seems to be

truer when numerous plants were in close proximity; some would be shaded by others and some would be exposed to the sun. Those plants in full sun tended to have worse damage, even though in contact with other plants. This was observed in coastal areas but needs to observed inland. Also, there seems to be a minor, though visible difference in damage levels between these adjacent North and South-facing plantings.

Along with leaf curling and leaf galls, K. myopori can also cause a streaking of the leaves so much so that a heavily infested plant will seem to look variegated (white and green foliage).