This very useful Guide to Invasive Plants in Massachusetts costs only $5.00 and is available through the Natural Heritage and Endangered Species Program.
What are invasive plants? and Why do we care about removing invasives and planting more natives?
This great and inexpensive guidebook will help you identiify and manage 66 of some of the most invasive plant species in Massachusetts. At only $5 (and less in bulk), if you don't have this guide, you should.
A fully laminated guide that will not dissolve in the rain, this has both close-ups and photographs of entire plants, making it useful for field identification of invasives. Unfortunately, it has only about forty species, but it does have many of the worst ones.
This is a more comprehensive book for identifying and learning about invasive plants across North America, and a good general reference.
Massachusetts Wildlife Natural Heritage & Endangered Species Program: Invasive Plant Information
This website of the Massachusetts Division of Fisheries and Wildlife provides more information about the work of the Massachusetts Invasive Plant Advisory Group, the classification of invasive species in Massachusetts, a listing of the regulated plants in the state, and some explanations of the biology of the issue.
IPANE: Invasive Plant Atlas of New England
This database gives us comprehensive information about the spread of invasive plants in New England— relying on professionals and trained volunteers throughout the region to supply information to the project. It has images, descriptions, and distribution maps of species listed, with articles and general information on the subject.
USDA Plants Database—Invasive and Noxious Weeds
The USDA Plants database is very useful site for looking up detailed information about the origin and characteristics of most plants in the United States. This particular portion of the site takes you directly to information about invasive plants and noxious weeds on a state by state basis.
Weeds Gone Wild
This is a great site on invasive plants with very detailed information, including recommeded methods for managing and controlling infestations. It's only drawback is that there are not yet fact sheets for all invasive species in Massachusetts or the United States.
Invasive.org--Center for Invasive Species and Ecosystem Health
This site lists over 1,500 species of plants that have been listed as invasive or noxious in North America. It has information on each species’ invasive characteristics and lists locations where it has been classified as noxious or invasive, referencing all sources. For many species, the site is also full of useful photographs to aid in identification.