I have two 40′ trees diseased with Phytophthora lateralis that I am having removed tomorrow. Can I chip the branches and spread them in my garden or will this spread the disease to other plants?
Although the following information from Washington State University Extension refers to a different species of Phytophthora, I imagine that the same precautions hold true.
Excerpt:
“P. ramorum can be spread to other hosts through air, water, rain, soil and plant debris. People can move it via plants, plant material, soil, plant products, wood, woodchips, dirty shoes, and water. P. ramorum does best in cool, wet climates (like ours).”
A resource from Oregon State University confirms this for both commonly found species of Phytophthora fungus:
Generally, one does not need to worry about plant diseases being spread by wood chips, because “they cannot compete well with wood-decay fungi. Uncomposted plant materials can, however, carry two important diseases of woody plants: Port-Orford-cedar root rot, caused by Phytophthora lateralis, and Sudden Oak Death (Phytophthora ramorum). Many diseased Port-Orford-cedar trees are disposed of by chipping, and mulch made from these chips can spread disease to healthy plants.”