The "tree root" at the left represents a time long ago when the first flowering plant appeared. The more branches it takes to reach a plant name at the right,  the more "highly evolved" it may be. The four groups at the top, whose names are given in orange, are ancient plants whose basic flower anatomy is considered to be primitive.

The names shown in colors other than red, and ending in "-ales," are the names of plant orders. As we see on our Pigeon-Holing Our Discoveries page, orders constitute the main grouping above the plant family level. The names in red at the far right are the names of well-known plants found in the order listed next to it. Once you become familiar with your local plants, you will see how the chart makes sense when it indicates, that -- in terms of basic flower structure -- "carrot flowers are somewhat similar to daisy flowers," and "grass flowers are a little like dayflower blossoms." Once you know your blossoms a little, it's fascinating to look at this chart.

Here's also a chart worth digesting:

If want to know the family of some other plant for which you know only the common name, you can determine its Latin name at the B & T World Seeds site. Once you have the Latin name, you can find its family name typing the Latin name into the search box at the NCBI Taxonomy Browser. On that page, the family's technical name will be given (Liliaceae instead of Lily Family, for example) along with the rest of its lineage. Remember that most plant family names end with -aceae. Once you have the technical family name, if you don't know what the common name is for the family, then Google the technical name, or look it up in a wildflower or horticultural book.

And if you find a qucker way to do it, let me know...