Citrus sinensis (L.) Osbeck
Received as a live tree from A.D. Shamel, USDA, 1923.
Apparently a limb sport of unknown origin.
Rootstocks of accession
Carrizo citrange, C-35 citrange
Season of ripeness at Riverside
November to January
Notes and observations
EMN, 1985: Tree furnished by A.D. Shamel. This is a limb sport. This accession had exocortis, removed by shoot tip grafting.
EMN, 11/1988: Only 2 fruits, both small & green, may be off-bloom. Entire fruit rind surface is very corrugated.
EMN, 12/14/1989: Light crop this season. Fruit rind is deeply corrugated with the raised ridges rough and darker orange color than the valleys which are very smooth like the rind of ordinary Thomson. Internal flesh coarse like Thomson. Typical navel orange flavor. Tree 7 had a large center non-corrugated limb (probably a regressive chimera) which I removed. Fruit on this limb seemed to be typical Thomson. Next-door limb may also have lost chimera for corrugation, but there was no fruit on it, so I left it. Watch & remove if needed. This is an interesting chimera, almost strange enough to put through clean-up and release as an ornamental, but probably not quite.
The fruit has raised, rough ridges on the rind that are darker orange than the valleys which are very smooth like the rind of an ordinary Thomson navel. Internally the fruit is the same flavor and texture of the standard Thomson navel. Occasionally the tree grows limbs that are non-corrugated, probably a regressive chimera. Corrugated Thomson would make an appealing ornamental.
1/10/2011, TJS: Please note that not all of the fruit on the tree will be corrugated, only approximately half of the fruit will have raised ridges. The lower right photo shows both types of fruit on the same tree. The trees are not very productive and always have a light crop even though the trees are large and appear to be in good health.
Not commercially available in California.