The crop from my three year old Orange Tree this year was plentiful but defective. I would describe the skin as wrinkled and defected. I did not use a Citrus Fertilizer but plan to this year. The tree has a multiple base and is watered regularly. Attached is a picture of the fruit. Any advice or suggestions is appreciated. Thank You!
Defective Orange Crop
Certified GKH Gardening Expert
The oranges may be developing in this manner from a nutrient imbalance.
I have listed a link to help with this issue.
You do mention the multiple base of your tree.
This is most likely the actual cause of 'odd fruit'
Most citrus trees are grown on a grafted stock. The root stock is from 'some type of hardy citrus'.
Root stock will send out sucker growth, if these are not removed, they will grow and began to take over the grafted tree.
The tree may revert to producing fruit from the root stock, not the grafted citrus tree.
The rootstock generally is a hardy, but less flavorful fruit.
I've listed some articles that explains this issue further.