Leafminer Damage In Satsuma’s

There is more and more interest in planting Satsumas in Georgia. They are a very tasty orange that is self-fruitful and ripens its fruit well ahead of any freeze problems (September to November). Although Satsuma’s have the best cold hardiness of citrus, they still need cold protection and irrigation. Fellow county agent, Jake Price in Lowndes County is researching varieties of Satsuma’s that do best in South Georgia. Here are about 100 new Satsuma trees recently planted after cold killed most this winter. These varieties are Owari and Sharanui.

I was asked to check on the leaves which were curling up as a result of a leafminer. The leafminers are either a fly or a moth. This is common in citrus and doesn’t cause much of a problem unless damage is very heavy. In a commercial field, treatment is still recommended. Eggs are laid on new leaves and the larvae mine underneath the cuticle of the leaf. The leaf will most times curl if damage is severe.

Leafminer in new Satsuma leaf

We can use imidacloprid to treat for leafminers. We can spray on the foliage which will stay for some time. Imidacloprid, like pyrethroids photodegrades. We can also drench imidacloprid into the soil which is taken up by the roots and provide longer control. UGA Extension Entomologist Dr. Will Hudson has this to say about drenching:

The drench rate for Admire (a 4.6 lb/gal formulation) varies according to the tree size, but it ranges from 10-20 trees per fluid oz. (14 oz/acre).  The amount to add to a bucket depends on how many trees will be treated with that batch.  You probably need to pour 1-2 qt. per tree, depending on the size (I use 2 gal per tree for pecan trees 8-10 inches DBH).  So, decide how many trees will be drenched, and add 0.05 fl. oz. per 3′ tree.  For the 2 lb material, the label suggests 3-6 ml per inch DBH (5 ml = 1 tsp) or about 1 tsp per 3′ tree.

I also saw some white flies. That along with the big Orange Dog caterpillars are some things we need to look for now. The Orange Dog caterpillar eggs will be orange under the leaves.