If possible, have a sample of the weed you are trying to identify in front of you. A magnifying lens will be helpful. The criteria listed on the left of the screen and labeled in the picture in the middle of the screen are those that are most helpful in distinguishing between broadleaf weed species. They are listed roughly in order of usefulness in identifying a weed.
NOTE: TO REVIEW THE MEANING OF A CRITERION CLICK ON THE CRITERION LINK AND A POP-UP WILL OPEN.
This program works by paring down the list of weeds on the right of the screen as you place checks next to characteristics that apply to your weed. For example, if you check the box under "Growth Season" labeled "summer annual weed," the list of weeds will be reduced from 47 to 11, with hairy bittercress becoming the first weed listed:
Note that all selected criteria are listed in the top center of the screen, above the broadleaf weed diagram. In the example above, note that "Growth Season: summer annual weed" is displayed as the only characteristic that has been checked so far.
If you next click "vining" under "Growth Habit," the list will be reduced to two weeds, starting with "blackberry." If you were then to check "one" under "Leaflet Number," no plants would remain in the list because there is no plant in the database that is a summer annual weed, has a vining growth habit, and has one leaflet per leaf. If you are not 100% certain that you have selected the right choice under a particular criterion, then uncheck the box.
It is not necessary to check a box under each criterion. Check only those characteristics that you know to be true of your plant.
You may view pictures and detailed information about any plant included in this program by clicking your mouse on the plant name on the right of the screen at any time.
Note that the plant description window for most of the weeds displays several pictures, a large one at the top of the screen, and several smaller ones on the bottom left of the page. For example, see the blackberry page below.
Clicking the mouse on one of the small pictures will bring up another window that contains a larger version of the picture.
Use the scroll bar to the far right of the screen to move down the page and view the list of characteristics and four small pictures:
Note that in blackberry example above, there is a note stating that the current page is the first of three pages. If you click the mouse on the "Next" icon, then the next page of four pictures will be displayed, and a "Previous" icon will appear. Clicking on the "Previous" icon will return you to the first page of four pictures, clicking on the "Next" icon again will display the third page of more pictures.
Clicking on the "Field View" icon, will bring up a picture of the weed in a natural setting:
Click on the link "View All" to return to the pages of small pictures showing plant details. Note that some of the plant characteristics listed in the table on the right of the screen are colored green and are underlined. If you click the mouse on one of these links, then pictures that show details of this plant structure will be displayed to the left. For example if you click on the "Leaf Venation" link for blackberry, the following screen will appear:
Return to the main broadleaf weed ID screen by clicking on the "Back" link in the bottom left corner of the blackberry page, or use the "Back" option on your browser.
For weeds for which we have management information in the TurfFiles Weed Management Program, a link is present at the top of the individual plant page that will take you directly to this program if you click on it:
Most botanical identification keys are based on the flower and reproductive structures of plants. While this approach is dependable, it is usually of little practical use for turf managers (since flowers and seeds are constantly being removed by mowing under most landscape conditions). Weeds in a turfgrass setting must then depend heavily on the vegetative characteristics of the plant. Note that flower color is listed as one of the criteria in this program, and can be used to distinguish between weed species, if the weed does happen to reach the flowering stage.