Sources for More Information
Bulletin #26: Understanding Landscape Cultivars
Staying current about cultivars on the market is not easy. The best method is to enter the cultivar of interest, or the species name, into a search engine. For example, "crabapple cultivars." This will provide leads to the hundreds of cultivars available and other news regarding that group of trees.
Handbook of Landscape Tree Cultivars
For many years this was the “bible” on cultivars of all landscape species. This fine publication showed the shape of the cultivar at age 30, provided descriptive information, and listed the person or organization that developed it. Today it is out of print but some copies are available at some libraries and through online searches.
Street Tree Factsheets
This is a valuable reference for over 200 cultivars and native species in the northern part of the U.S. Full color photos accompany each tree and a color code provides quick access to trees by size classes. It also includes a thorough bibliography. Available at amazon.com.
Manual of Woody Landscape Plants
This classic by Michael A. Dirr is a “must have” for arborists or anyone with a serious interest in trees. Its 1,187 pages includes detailed and authoritative descriptions of species and lists brief descriptions of important cultivars of those species. Available at amazon.com or Stipes Publishing Company
Information about Plant Patents
For an explanation of plant patents and how to apply for one, a helpful link is about.com.
For information about the National Association of Plant Patent Owners, contact AmericanHort.