Q: Does 25% Undivided interest in a 1.03 ac parcel need to go through probate? Also oil & mineral rights that pay $50/yr?

A: Based on the information provided, it seems there are a few key considerations:

1. Probate requirement: In California, assets that were not properly transferred into a living trust before the person's death generally have to go through probate. This would apply to the 25% undivided interest in the 1.03 acre parcel and the oil & mineral rights, since you mentioned they were not included in your mother's trust.

2. Small Estate Affidavit: California does offer a simplified process for transferring property if the total value of the probate estate is under a certain threshold (currently $184,500). To qualify, you'd need to determine the value of your mother's 25% interest in the property plus the oil/mineral rights. Getting the property professionally appraised would help determine if you fall under this threshold.

3. Property condition and access: The deteriorated condition of the house and the landlocked nature of the parcel could significantly impact the property's value, which may work in your favor for staying under the small estate threshold. However, the limited access could make the property harder to sell if desired.

4. Oil & mineral rights: The $50/year payments suggest these rights may not be particularly valuable. But it's still an asset that would factor into the total estate value.

So in summary, unless the assets clearly fall below the $184,500 threshold, probate is likely necessary. Consulting a probate attorney could help you evaluate the property, determine the best approach, and potentially avoid full probate if the simplified process applies in your case. The unique aspects of this property may require some professional guidance to resolve.