Table 1. Effect of systemic insecticides on birch leafminers

	Means^¹
Treatment	% Damaged leaves	Number of reared adults/100g fresh leaves	N^²
1.5% NSE	14.0b	11b	5
3.0% NSE	7.8c	3b	6
Injecticide-Bidrin	1.6d	4b	5
Injecticide-Meta-Systox-R	16.7b	25b	6
Soil-Injected Meta-Systo×R	3.8cd	2b	5
Water	40.8a	160a	6

↵1. Means within column followed by the same letter do not differ significantly (P=0.05; Duncan’s (4) multiple range test).
↵2. N equals the number of trees treated and sampled, five branches per tree.