Different species of tree, like different species of plant or flower, need different soil requirements. Some trees prefer slightly acidic soil, some need nutritious loam soil and others prefer the water retention of clay soil. To know what type of tree grows best in your lawn, or to see if it is suitable for a tree that you may have in mind, you must test your soil's type, acidity and drainage.
Test your soil's pH levels. There are many ways to do this. One is to purchase an electronic pH meter which, when inserted into the soil will give you an accurate measurement of your soil's pH.
If you do not want to invest in a pH meter, some gardening and home improvement stores like Lowe's will test a prepared soil sample for free (see Lowes.com for details).
Another free alternative is to test your soil's pH level yourself. Unearth a few inches of soil with your spade. Scoop out a sample at that depth and dump it into a bucket. Then add a half-cup of vinegar. If your soil bubbles, then its highly alkaline. If it doesn't, take another spadeful of soil and add a half a cup of water and mix it into the soil. Then, take a half-cup of baking soda and mix it in. If it bubbles, then your soil is highly acidic. If neither combination causes a reaction then your soil has relatively balanced pH. This method will only tell you if your soil is highly alkaline or acidic, but as most trees grow in relatively pH balanced soil this will be enough to warn you if your soil is currently unsuitable for growing certain species.
Determine what type of soil you have in your yard. The three general types of soil are clay, loam and sand. Most soils are a blend of two types. When testing your soil type, dig a few inches into the ground and sample the soil there.
Clay soil test:
Take a handful of soil in your hand in your hand and squeeze it. If the soil retains the shape of your hand or fails to break apart then you have clay soil.
Sandy soil test:
Take a handful of soil in your hand and squeeze it. If it crumbles immediately, your soil is sandy.
Loam soil test:
Loam soil is a combination of sandy and clay soil types and is the most prevalent in the United States. Take a handful of this soil and squeeze it. It will neither stick together like clay soil or crumble like sand but lie somewhere between the two extremes.
Test your soil's drainage. Dig a sizable hole in your yard (ideally where you plan on planting your tree) and fill it with water. If the water is still there in the morning, then your soil drains poorly. If it is gone in a few hours then your soil drains quickly. Most soils will lie somewhere between the two.
Test your soil's fertility. The only way to test the available nutrients in your soil is to get a soil fertility test kit. These can be a rather expensive and unnecessary purchase. If you are in doubt about the fertility of your soil, amending it with compost and or a fertilizer is much more cost effective and something you may have to do after purchasing the expensive test kit anyway.