I have a 10-year-old brown turkey fig tree. For the last four years, I have been bothered by leaves showing brown spots, including on the stems. The spots get larger, starting just before harvest time.
I have been told by experts that the culprit might be a red rust, but not a soul in Placer or Sacramento knows for sure. I even sent samples to both counties.
I went to the nursery and bought a product for treatment of red rust and a few other conditions. The product used was copper based; it hasn't helped.
Each year, I mix about 10 gallons using the aforementioned product. I pour this on the ground in a 4-foot radius of the tree.
I also spray the dormant tree about three times per year. I also pull back all groundcover around the tree. But still I see spots. Help!
Tom Walker, Roseville
According to UC master gardener Carol Hunter, figs are a rewarding, easy-to-grow tree with few insect and disease issues. One possibility for your mystery sports is fig rust (Physopella fici), which produces light- orange spots only on the foliage. Those leaves eventually drop from the tree.
Another possible condition is fig mosaic, which is a virus. On leaves, mosaic spots are distinctly yellow, contrasting with normal green color of the foliage. The margins of the yellow spots blend gradually from a light-yellow color into the dark green of healthy tissue.
These spots may be uniformly scattered over the surface of the leaves or may appear as irregular patches of light green, diffused widely throughout the leaf blade.
Later in the season, a rust-colored band develops along the border of the mosaic spots. This condition can be spread by cuttings and a mite.
The www.ipm.ucdavis.edu website includes extensive information on figs, including cultural tips, and pests and disorders, along with photos.
The exact condition you describe with "brown" spots on fig leaves cannot be identified. Brown foliage may also be caused by improper watering (not enough) or overfertilizing, but those brown areas appear mostly on the leaf margins not just spots.
We would be interested in knowing the name of the product that has been applied to the tree. That may have an effect, too.
To get a more precise diagnosis, bring samples of spot-free foliage, as well as foliage with spots and stems, to the Sacramento County UC Cooperative Extension office for an evaluation. The office is at 4145 Branch Center Road, Sacramento.
Hours are 9 a.m. to noon and 1 to 4 p.m., Monday through Friday.
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