Texas Lightning by Caroline Clemmons

How can two people from different eras own the same ranch?

Penelope Jane Terry knows everything about ranching in spite of being a lone woman. She is determined to send to jail the rustlers who believe they can steal what is hers… until she is caught spying on their dirty works and must ride for her life. What Penny doesn’t count on is being hurtled over a 120 years into the future.

Jake Knight believes the attractive woman who stumbled into his home one rainy evening either has amnesia or is certifiably insane. Unless, that is, she is in league with whoever is trying to drive him out of business. Someone is trying to force him to sell his ranch by staging a string of damaging incidents. Jake’s been kept so busy making repairs that he can’t run his ranch. Even if he were stupid enough to wish to sell, the ranch is so firmly entailed that no one can break the conditions.

Jake gradually learns Penny is who she claims, no matter that time travel is supposed to be impossible. They’re locked into a clash that it seems only one of them can win. If an outsider weren’t trying to kill Jake as well as bankrupt him, perhaps he and Penny might be able to reach an agreement. But, there is that treasure….