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WSU Puyallup Managing Phytophthora diseases in the nursery

Plants photo gallery

Confirm that nursery stock is purchased from a licensed, certified shipping nursery or that material is propagated on-site.

Inspect all incoming nursery stock (buy-ins, transfers, and returns) prior to introduction into the nursery facility. Avoid mixing incoming plants with existing stock until plants have been examined for disease symptoms by trained personnel. Plants to be inspected
For buy-ins of high risk plants, suspend the use of Phytophthora specific fungicides on 10% or 100 plants, whichever is smaller, for a 2 month period. This will show if fungicides used by the seller were suppressing symptoms prior to purchase.High risk plants for P. ramorum include rhododendron, camellia, pieris, kalmia, and viburnum. High Risk Phytophthora Plants
Arrange plants to minimize damage caused by P. ramorum should it enter the nursery.Avoid mixing high-risk genera (Rhododendron, Camellia, and Viburnum) with other host and non-host plants. It is recommended to keep a 2 meter break between high risk plants and other material. IMG_5475_2
Manage weeds on the nursery site as they could serve as alternate hosts for diseases or be potential reservoirs for disease organisms. weeds in gravel
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