Hi Cynthia,

I can't find any specific sources on this from OSU. I wouldn't put a lot of faith in the information from the Norfolk Botanical Garden since they don't include any references, but all the information from the Water Use Site comes from 2 different scientific studies, so should be fairly credible. I took a look at both of the original studies and they were consistent with what's presented in the table on the water use site. Good find on that source!

In addition, I found a factsheet on Italian Cypress (Cupressus sempervirens) from University of Florida Extension that lists it as a coastal species and says it has moderate tolerance aerosol salt (salt spray) and good tolerance to soil salinity (salt in the soil/sand). Based on this information, it sounds like Italian Cypress should be an acceptable choice for the Curry County coast.

There was less information available on Leyland Cypress (Cupressocyparis leylandii), but the only source that appeared to test its tolerance to soil salinity found it sensitive. I would worry that this species might be a problem so close to the coast, as species subjective to soil salinity are likely to be pretty sensitive to salt spray as well.

Not sure if your Plant Clinic client is wanting to plant these as a wind break, but I also found a WSU extension publication on planting windbreaks that may or may not be relevant.

The OSU publication Growing Berries on the Coast also discusses salt briefly, indicating that sites within 100 feet of the ocean are likely to experience salt damage. I would imagine this to be true for most plant species, even fairly salt tolerant ones, so I would encourage the client to plant at least that far away from the ocean, and further if possible to decrease the risk.

I hope this helps! Please let me know if you have any follow up questions.

Sincerely,

Shannon Rauter

Clatsop County Master Gardener and Small Farms Program Coordinator