Author: Gail Langellotto

Master Gardeners provide research-based recommendations for the home gardeners, community gardeners and others who grow for fun, relaxation or other non-commercial reasons.

Plant Clinic Procedures:

In most counties, Master Gardeners staff Plant Clinic phone lines and desks at county Extension offices.  Many counties also offer Plant Clinics in their communities, (i.e. at farmers’ markets, fairs or garden retail outlets).  Plant Clinics are a valuable service to the community, where Oregonians can ask questions about their home or community garden.  Those who utilize the services of a Master Gardener Plant Clinic are often referred to as our ‘clients’.  To ensure high quality answers to questions received at Master Gardener Plant Clinics, it is important that volunteers are trained to recognize and utilize appropriate resources and to consult with OSU Extension faculty and/or expert Master Gardeners, as needed.

Appropriate resources include the Pacific Northwest Weed, Insect and Disease Management Handbooks; peer-reviewed journal articles, OSU Extension publications, brochures and hand-outs; eXtension and/or university Extension websites; online materials produces by eXtension and/or university Extension Services; and other resources that contain validated, research-based content.  In addition, to utilizing county Extension faculty and expert Master Gardeners, on campus resources (e.g. OSU Plant Clinic; OSU Herbarium, Oregon State Arthropod Collection), Extension specialists, and other OSU faculty should be consulted when needed.

Master Gardener volunteers should utilize these resources to provide research-based information to those seeking information or advice on home and/or community gardening.  Master Gardener volunteers are not permitted to answer questions for commercial growers, or questions related to commercial production.

Master Gardener Plant Clinics accept plant (live, dead or preserved), arthropod (dead or preserved) and soil specimens for assessment.  Safety of the volunteers is paramount.  For this reason, the Master Gardener Plant Clinics will not accept swabs, tissues, hair or other specimens of human or animal origin; articles of clothing, bedding or towels; personal hygiene items such as toothbrushes, hairbrushes or any other items that may be contaminated with human or animal pathogens, parasites or secretions.  Clients with questions about possible human or animal health need to direct those inquiries to the appropriate public health or veterinary experts in the community.

A check list of the of what Master Gardeners can and can not do in plant clinic can be found below.

Occasionally, a client may submit a sample to or seek advice from the Master Gardener Plant Clinic that could have implications for human health.  Examples include:  bed bugs, spiders, suspected arthropod-caused skin lesions, pesticide poisoning, poisonous plants, etc.  If this is the case, it is important to remember that Master Gardener volunteers are not permitted to offer medical evaluations, diagnoses or advice on treatment.  Instead, the client should be referred to a trained professional for these services.  Master Gardener volunteers are permitted to utilize appropriate resources to identify a plant or arthropod sample (e.g. bed bugs, poison ivy) – but not lesions, rashes or other symptoms that may have been caused by a plant or an arthropod (e.g. the bite marks or rash that could be caused by bed bugs or poison ivy).  OSU Extension faculty staff and volunteers should refer all clients seeking advice on managing any potential life/safety situations to medical or other trained professionals.

Often, the samples that are submitted to Plant Clinic make it difficult to confidently arrive at an accurate identification.  For example, the client may submit only a small portion plant foliage, or may submit a crushed arthropod sample between two pieces of tape.  If this is the case, and especially for those cases where the identity of the plant or arthropod could have implications to human health (i.e. a doctor would treat a patient who ingested a non-poisonous plant different than they would a patient who ingested a poisonous plant), it is important to use appropriate language when communicating findings to a client.  An example of appropriate language is:  “Based upon the information provided to OSU Extension and from the research conducted, it appears that this plant is a XXXXXX plant, which is listed as not poisonous.”

Master Gardener volunteers working in the Plant Clinic should be provided with continuing education and support, to ensure that they are current on information, understand appropriate resource use, recognize when they should seek additional help or support, and know that it is more important to accurately say ‘we can’t answer that question’ (for whatever reason – not enough plant material, sample to crushed to identify, no research based resources on the topic) than to provide an incorrect answer.

OSU policy for Master Gardener recommendations to clients:

• Use appropriate research-based resources when providing recommendations.  Examples of research-based resources include the PNW Handbooks, OSU Extension Publications, other Extension publications, peer-reviewed journal articles.
• MGs are not allowed to suggest homemade pesticides to clients. In addition to poor efficacy and potential plant injury, many homemade pesticides violate federal law. There are two laws that address this issue, the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) and the Federal Food, Drug and Cosmetic Act (FFDCA) Section 408. More information on this issue can be found here:
  • ‘Are homemade pesticides legal?‘ (Michigan State University)
• Master Gardeners are objective in their recommendations, and thus inform the client of all research-supported options:  Cultural, biological, and chemical (synthetic and organic).  Even if you do not use synthetic chemicals in your own garden, you should not exclude this option – so long as it is research-based – when making recommendations to the client.
• Refer commercial clients to an appropriate extension agent

OSU Extension Master Gardener Program Stance on Select Gardening Topics:

As research on sustainable gardening practices continues to grow, we are learning more and more about those practices that methodologies that are backed by objective research.  Below you will find links to topics that have been reviewed by OSU faculty against the current published literature on the topic, and our current stance on what constitutes a research-based recommendation for that topic.

• Compost Tea Policy: Research suggests that compost teas are equivalent to composts and inorganic fertilizers, as a source of plant nutrients and in their effect on plant growth. However, we are not able to make a clear recommendation on the use of compost teas as a disease suppressant.
• Marijuana Policy:  Oregon State University and the Oregon State University Extension Master Gardener program are recipients of federal funding.  Oregon State University and the Oregon State University Extension Master Gardener program are also governed by the federal Controlled Substances Act, the Drug-Free Workplace Act and the Drug Free Schools and Communities Act.  Thus, to guard against risk of losing Federal funding and to adhere to the federal laws that govern our activities, OSU Extension Faculty, Staff and Volunteers do not provide advice or referrals on the culture, care and/or use of marijuana.