Reciprocating Saw for Firewood?
I recently bought a porter cable set. The set consists of: a circular saw, reciprocating saw, drill, 18V NiCads & charger.
I might as well also make use of the set for trimming my numerous overgrown shrubs (taller than me already), and for cutting firewood.
Which blades should I buy to use on my reciprocating saw for those purposes?
The tools that you have purchased are best used for carpentry purposes. A reciprocating saw is not suitable for cutting firewood or trimming shrubs.
In regards to trimming shrubs, you will have difficulty getting the saw to work because it needs pressure to cut. This is nearly impossible on shrub branches as they will flex and bend under the pressure. Your best bet is to buy some hand clippers or hedge trimmers (depending on what type of shrubs/hedges you have). Ideally, for the optimal health of the shrubs, I recommend hiring a certified arborist to prune them for you.
In terms of firewood, a reciprocating saw simply isn't the right tool for the job. Is it possible? Sure, on small pieces of wood with the proper blade but it's really not worth the effort. I would compare it to shoveling the driveway with a plastic spoon. It'll get the job done eventually, but you're gonna break a lot of spoons. A chainsaw is really the only suitable tool for the job.
The good news is that you don't need to buy a chainsaw, most tool rental companies carry them in stock. You can rent one fairly cheap and get the job done much faster. If you don't have experience with a chainsaw, I recommend taking a safety course or learning from a friend with experience. Also, always wear protective chaps, a helmet, and eye protection when cutting firewood.
Good luck and be safe!