Leaving your cedar exposed to the elements for weathering can damage the cedar especially in excessively wet climates.
Seal small space between wooden siding.
How to seal siding to keep out mice.
Seal a door frame in place and seal the subfloor at the bottom of a door frame.
Correctly sized backer rod a bond breaker and properly applied sealant is the appropriate way to handle the joint between dissimilar materials with different coefficients of expansion both thermal and moisture such as wood trim and cement plaster.
Find the entrances mice use to enter your home.
Crawl around the exterior of your home and use a flashlight to find cracks holes and gaps.
It will look like crap and on top of that like you already indicated it will be hard to put in there in the first place.
Use a small.
You can choose to use something like 1x2 inch cedar strips.
Use latex painter s caulk inside of doors and windows or to quickly fill cracks and holes in drywall.
Best for use with drywall wood and masonry.
It needs to move and breathe.
Slowly move down the joint to apply a steady bead of caulk into.
The proper approach to this is to install vertical strips of wood over the cracks from the outside.
In my opinion caulking between the seams in any lapped siding either horizontal or vertical is not good practice but not just because of any potential vapor barrier effect.
Fill in gaps between crown moulding and baseboards.
Smooth the caulk bead with your finger and begin caulking the joint between the fascia board and the soffit also known as the eave.
Think of a wood home as a living thing.
While my experience is more with vinyl siding sealing the siding to the foundation would deny any moisture that developed behind the siding from driving rain between seams in the siding condensation behind the siding ect an exit at the bottom.
Look under the siding at the area meeting the foundation of your home for holes and gaps.
The siding expands and contracts with temperature and humidity.
Use to install wood paneling without nails.
Cover as much of the wood as you can with sealant using a small brush to get into the spaces between panels if the siding is already installed.
I would be hesitant to seal the siding to the foundation.