Table 3.

The injury index scores for ozone symptoms on the Gleditsia triacanthos inermis ‘imperial’ and the Platanus acerifolia ‘Bloodgood’ at each site and for each year are shown below. Although there was considerable variation in the numerical scores, these two cultivars were consistently the most ozone sensitive at all four sites and for all three years.

Cultivar	Location	Injury index score¹
Cultivar	Location	1977	1978		1979	Average
‘Imperial’	Rikers Island	19	182		152	118
	New York Botanical Garden	—	215		52	134
	Cary Arboretum	180	175		160	172
	Rutgers	—	66	89	112	89
		Cultivar Average:				131
‘Bloodgood’	Rikers Island	195	132		75	134
	New York Botanical Garden	—	65		40	53
	Cary Arboretum	90	53		100	81
	Rutgers	—	114		120	117
		Cultivar Average:				98

↵1 Based on the four trees of each cultivar at each location and using the maximum injury scores for that growing season.