Objective  Changes and classification on leaf color of various varieties of ornamental crabapple were studied to facilitate the germplasm collection and utilization.

  Method   Color values and pigment content of leaves on 42 specimens of ornamental crabapple (Malus spp.) were determined using chromometer and spectrometer.

  Result   ① The distributions of the CIELCH color space measurements on luminance (L*), color saturation (C*), and hue (h*) of the leaves from July to September showed it to be relatively scattered in July, stratified in August, and shifting to the left on the values in September. ② The leaf color in July clustered the 42 crabapple varieties into Group A with the ranges of L*=28.95−32.63 and C*=12.32−14.60; Group B, L*=26.98−32.11 and C*=9.09−13.39; and, Group C, L*=32.10−35.22 and C*=14.33−18.01. L* and C* of these 3 groups differed significantly in the order of C＞A＞B. Trees in Group C appeared bright and full in color and were classified as bright green varieties. ③ The relative pigment (chlorophyll) content in leaves of Group B was 4.285%, which was significantly higher than that of Group A at 3.786% and Group C at 3.785%. With the deep green color and low L* and C*, Group B was named the dark green varieties, while Group A was simply termed green varieties.

  Conclusion   The 9 ornamental crabapple varieties in Group C were judged to have the highest potential commercial value among all in the season.