Wood-prep ideas to enable earthen plaster to adhere?

Anyone using earthen plaster on wood exterior surfaces? I'm looking for ideas to prepare the wood to receive earthen plaster so that the mud really sticks. The building is adobe with wood bond beam and I would like to cover the wood with mud. I prefer natural solutions that don't use metal lath. I will resort to metal as a last resort. Thanks in advance for sharing your ideas and experience.

When at a strawbale workshop, we used slip and burlap to help the earthen plaster to adhere to the wood framing. Slip is just thinned earthen plaster without the straw or whatever you are using for strength, that is sprayed on with a sprayer that is used for texturing interior walls, so like a paint sprayer but for thicker material.

After testing some burlap on wood using Stacy's suggestion to coat with slip, this appears to be a fantastic approach.
Using a staple gun, I attached the burlap to a smooth scrap of 2 x 6. I mixed a "slip" with clay-sand-silt mix from the yard. Due to my concern about adherence, I added 1 part cooked flour paste to 3 parts dry clay mix then added enough extra water to make a pancake-batter consistency. Using a large wallpaper paste brush, I coated the damp burlap thickly with the mix and scored the surface for texture. The test board dried for 2 days indoors (due to a snow storm). The burlap with staples is really secure but there is no sign of clay flaking at the edges: adhesion is solid.
A friend gave me a pile of burlap coffee bags that should cover the wood and I ordered a $35 texturizing spray gun with slip compatible hopper to attach to an air compressor to spray the entire bond beam. I expect this automation step will go fine after I find the right consistency for the slip to work with the texturizing attachment. If I learn anything more, I'll report back after the project.
Thank you Stacy for your help here. I am so grateful!

You're welcome. Glad I could help.