Farmers and ranchers know the difference between hay and straw, but the average homeowner often confuses the two.  Both are available in homeowner sized bales, typically rectangular in shape, and both can be used for many home and garden projects.  Understanding the differences and benefits of each will help you make a decision on which product to choose.

Step 1:  Hay is a somewhat universal term for many different types of grasses that are cut, typically before they set seed, and baled into large or small, round or square, tightly tied bundles.  These bundles can be stored for several years or used immediately for animal feed.  Choose hay from crops specifically planted for forage, such as alfalfa or timothy grass, to feed various animals.

Step 2:  Straw is the hollow shaft left over after crops have been harvested.  The stiff, hollow composition of straw makes it a great insulator.  Straw decomposes at a much slower rate than hay, has a very low moisture content and has no nutritional value.  Choose straw for bedding, erosion control, building and insulating purposes.

Step 3:  Straw is great for mulching garden paths and is the product of choice to insulate a freshly seeded lawn.  Unfortunately, along with straw comes a number of rogue seeds that are bound to germinate in the most unfortunate places.  Watch for large seed heads when spreading straw and be ready to pull up any unwanted crops before they take a foot hold in the yard or garden.

Step 4:  While straw is a great mulch for paths and walkways, hay is a wonderful soil amendment.  Fresh cut hay is too wet and green to be used effectively for mulch, but aged hay, a year or so old, contains nutrients that can enrich the soil.  Unlike straw, hay decomposes quickly and builds the soil while temporarily protecting the plants.  Choose hay to mulch around garden crops or to spread over a newly seeded lawn.  Work the hay into the soil as it decomposes.

Step 5:  If the threat of weed seed is too much to bear, solarize hay to kill off any seeds that may be lurking within.  Pile the hay in a sunny spot, soak it with water and cover it with 1 to 2 mil thick clear plastic sheeting.  Allow the sun to bake the hay for four to six weeks before using it in lawn and garden areas.