Hannah M Mathers

Dr. Hannah M Mathers

Mathers Envir, Sci, Service, LLC
839 Riva Ridge Blvd
Gahanna, OH 43230
Office: 614-371-0886

Dr. Hannah Mathers has over 26 years of experience and training in weed control in landscape and nursery crops, and is accomplished in herbicide chemistry, plant biochemistry, plant physiology and agricultural statistics. For the past 5 years, Hannah has been employed as an Independent Researcher/ Consultant/ Owner, Mathers Environmental Science Services, LLC. Before that she was an Assistant Professor and Professor at Oregon State and Ohio State Universities, respectively. Dr. Mathers’ has distinguished herself as a weed control scientist and speaker in nursery/ landscape crops. She has conducted thousands of herbicide efficacy and phytotoxicity trials, invented five new bio-herbicides, assisted in the registration of twelve new herbicides in the US.

Areas of Expertise
  • Agricultural
  • Biochemistry
  • Biology
  • Chemicals
  • Chemistry
  • Crops
  • Environmental
  • Forestry
  • Marijuana
  • Pesticides
  • Stormwater Retention Pond
  • Vineyards

Expert Background
Q: Please list your professional accreditations, degrees, licenses, and certificates granted:
A: • Ph.D, Horticulture, Michigan State University, 1997. Dissertation: Evaluation of Prunus cerasus Germplasm for Cold Resistance.
• M.S., Plant Science, University of Saskatchewan, 1988. Thesis: Seedling Screen of Malus for Cold Resistance with Application in an Inheritance Study.
• B.S., Plant Science/Pomology, Cornell University, 1986. Associate in Agriculture, Horticulture, University of Guelph, 1980.
• Forest Technician's Diploma, Forestry, Sir Sandford Fleming College, 1978.
• Agriculture Diploma, University of Guelph, Guelph, Ontario. 1980.
Q: Please list your affiliations or memberships in any professional and/or industry organizations:
A: American Society for Horticultural Science

Weed Science Society of America

International Plant Propagators Society

American Conifer Society
Q: Please list any teaching or speaking experience you have had, including subject matter:
A: • I have delivered 381 (180 in-state) presentations. 55% of these 381 (213) presentations were out-of-state (78% invited) to 20,526 clients in 27 states, 17% of these were out-of-country (100% invited) in five Canadian provinces and three other countries (Denmark, England and Germany). 45% (180) were in-state presentations (72% invited) to 22,726 clients (see summary table below) (A detailed listing is available on request). Most of my speaking and teaching is in weed control, sustainable landscape management, nursery production, plant nutrition and cold hardiness of woody plants.
Q: Have any of your accreditations ever been investigated, suspended or removed? (if yes, explain)
A: No
Q: On how many occasions have you been retained as an expert?
A: 40
Q: For what area(s) of expertise have you been retained as an expert?
A: Herbicide drift
Herbicide residue in soils
Toxicology of herbicides for an applicator
Exposure and toxicology to stored herbicides
Environmental toxicology related to herbicide over use
Incorrect herbicide applications
Cold hardiness of woody plants
Incorrect plant media in nursery production
Weed identification and problems of noxious weeds
Horse poisoning with noxious weeds
Stormwater retention ponds pesticide use.
Q: In what percentage of your cases were you retained by the plaintiff?
A: 70%
Q: In what percentage of your cases were you retained by the defendant?
A: 30%
Q: On how many occasions have you had your deposition taken?
A: 6
Q: When was the last time you had your deposition taken?
A: 2021
Q: On how many occasions have you been qualified by a court to give expert testimony?
A: Twice
Q: On how many occasions have you testified as an expert in court or before an arbitrator?
A: Twice
Q: For how many years have you worked with the legal industry as an expert?
A: 12
Q: What services do you offer? (E.g.: consulting, testing, reports, site inspections etc.)
A: • Consulting:
-Woody plant cold injury
-Herbicide programs
-Herbicide injury
-Nursery production
-Fertilizer programs
• Testing:
-Electrical Conductivity
-Research plots
-Statistical analysis
• Site inspections
• Statistical analyses
-Small and large plot research trials
-Analysis of variance
-Principle component analysis
-Regression analysis
-Plotting and graphing of data
Q: What is your hourly rate to consult with an attorney?
A: $285.00 / hr.
Q: What is your hourly rate to review documents?
A: $285.00 / hr.
Q: What is your hourly rate to provide deposition testimony?
A: $315.00 / hr.
Q: What is your hourly rate to provide testimony at trial?
A: $315.00 / hr.
Q: Please list any fees other than those stated above (E.g.: travel expenses, copy fees, etc.)
A: Travel costs, materials and supplies for any testing or evaluations.


References upon request.