Rates of O3 uptake by 4 seed-source progenies of red maple from an atmosphere containing 0.2 ppm 03.*
| Seed Source | O3 uptake | |
|---|---|---|
| mg O3/hr/dm2 | mg O3/hr/g | |
| State College, PA | 0.315a | 0.634a |
| Opelika, AL | 0.217b | 0.490b |
| Alfred, ME | 0.266bc | 0.557ab |
| Ely, MN | 0.231c | 0.545b |
↵*Mean separation in columns by Duncan’s multiple range test, 5% level. Values represent the means of 20, 26, 22 and 20 seedlings, respectively. (From: Townsend,A.M. 1974. Sorption of ozone by nine shade tree species. J. Amer. Soc. Hort. Sci. 99: 206-208).