If I was injured by an employee of the farm, do I still have a claim against the farm owner?

Probably. An employer may be held liable for acts of an employee that cause injury to another person if the act was foreseeable and was in the furtherance of the employer’s business. An employee’s act is generally within the scope of employment when it is in the furtherance of the  business and when the employer is, or could be, exercising some degree of control over the employee.