Chainsaw broke. Have a reciprocal saw, I wonder what is the best wood blade
I can use for small tree limbs. How many teeth should it have.

You want to use the blade with the largest teeth you can find. This will cut the best without the sap in the wood clogging the teeth. If your cutting 1" to 4" diameter branches, I would recommend using a bow saw. These have very large odd shaped teeth and will cut through faster than you think. You will be surprised at how effortless it is. Just remember to use the full length of the blade and let the saw do the work. It is also much safer than using a chain saw or power saw on ladder.