Answer: What you describe sounds like "peach split pit", which can also affect apricots. It's a physiological disorder of unknown cause, but may be associated with too much heat or early fruit thinning. Nectarines should bear well in your area, but sometimes fruit trees go into a habit of alternate bearing (producing lots of fruit one year and very few the next). Another possibility is lack of sunshine, not enough water, or no pollinating insects. If the nectarine tree looks otherwise healthy, it's probably a weather related problem. Prune it back this winter to encourage healthy new wood, which should develop new fruit the following year.
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