The soil in my yard is very stony I really want to be able to be able to grow root crops. Is there anything I can use to remove the rocks or will I simply have to dig them out and remove by hand? Is it best to invest the effort in raised beds?

Removing rocks in going to be a process no matter what you do. It might be worth it so set up one or two raised beds to use while you're working on the larger garden plot. They'll dry out quicker in the spring, allowing you to get a jump on the gardening season, also--it's easy to set up mini hoop-houses with a raised bed, to extend your season into the fall.

To remove the rock in your larger plot, you can start with a rake and pry bar for rock on the surface, and use a wheelbarrow to move them away from the garden spot.

To remove rocks beneath the surface garden tractors (if you're so fortunate to have one) come with a number of different attachments, such as grading blades, heavy duty plows, and large gardening rakes. If you do not have access to a tractor, try loosening the soil with a rototiller, use a garden fork, or the tried and true shovel.

Finally, a soil sieve or screen can be used to sift the soil to eliminate the smaller rocks.

Check out this link for more info: http://www.ehow.com/info_8000785_tool...

I garden on glacial till which is rock filled. To start a new bed I dig down 1 foot, dumping the dirt on a mesh screen covered wheelbarrow. The rocks go to the edge to form a path. I mix the remaining soil with compost (no manure if you're growing potatoes) and dump it back. I also add 1 to 2 feet of compost mix to create a raised bed to ensure good drainage. Happy Spring, K

If you're in my boat and have more energy than money you can remove all the rocks, but it's labor intensive.Buy a piece of hardware cloth about 2 foot square and attach a 2x4 box framework to hold the hardware cloth stiff. Put the box on top of an empty metal drum and shovel some soil onto the box. Take another piece of 2x4 and scrape back and forth across the box until all the soil falls through into the barrel.All the rocks will be left on top of the hardware cloth leaving you with very improved soil...and a sore back.
Raised beds are much, much easier if you can afford to have that much loam brought in. lasagna gardening pops to mind if you want to build some nice beds. There are also vertical growing techniques for potatoes you may want to explore. Good luck!

Lee valley tools makes a great item known as a rock rake its basically for picking up loose rocks but makes the process less back breaking. I second the raised bed idea there are some great articles about turning pallets into raised bed planters and lots of places want you to take them for free