Thanks @Lugina, Sorry that I don't have any idea for pollen allergy. but I have very good references for you. I ordered them expecting that it'll give me a good idea. Hope it will help you.

1. Prescription for Herbal Healing, 2nd Edition: An Easy-to-Use A-to-Z Reference to Hundreds of Common Disorders and Their Herbal Remedies

1. Prescription for Nutritional Healing, Fifth Edition: A Practical A-to-Z Reference to Drug-Free Remedies Using Vitamins, Minerals, Herbs & Food ... A-To-Z Reference to Drug-Free Remedies)
2. Aromatherapy for Women: A Practical Guide to Essential Oils for Health and Beauty I have korean translation, it has useful information for aromatherapy. it is very useful tool as simple remedies.