If possible, have a sample of the turf or weedy grass 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 grass species. They are listed roughly in order of usefulness in identifying a grass.
This program works by paring down the list of grasses on the right of the screen as you place checks next to characteristics that apply to your grass. For example, if you check the box under "Seedhead / Flower" labeled "panicle," the list of grasses will be reduced from 29 to 11, with barnyardgrass becoming the first grass listed:
Note that all selected criteria are listed in the top center of the screen, above the grass diagram. In the example above, note that "Seedhead / Flower: panicle" is displayed as the only characteristic that has been checked so far.
If you next click "folded" under "Vernation Type," the list will be reduced to five grasses, starting with "bluegrass, annual." If you were then to check "absent" under "Ligule Type," no grasses would remain in the list because there is no grass in the database that has a panicle type seedhead, has folded vernation, and lacks a ligule. 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 grass.
You may view pictures and detailed information about any grass included in this program by clicking your mouse on the grass name on the right of the screen at any time.
Note that the plant description page for most of the grasses 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 Kentucky bluegrass 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 Kentucky bluegrass 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 containing more pictures:
Clicking on the "Field View" icon, will bring up a picture of the grass 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 "Ligule Type" link for Kentucky bluegrass, the following screen will appear:
Return to the main grass ID screen by clicking on the "Back" link at the bottom corner of the Kentucky bluegrass page (not showing in the pictures above), 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 grass seedheads are constantly being removed by mowing under most landscape conditions). Turfgrass identification must then depend heavily on the vegetative characteristics of the grass plant. Additional clues for aiding turf identification are often very obvious factors like the time of year, cutting height, predominant soil moisture conditions, and degree of shade present. For example, an actively growing turf during the cool portion of the year is most likely a cool-season species. Bermudagrass is not likely to be present in a deeply shaded site, particularly with a northern exposure. Note that seedhead/flower 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.