Abstract

KNODEL, J.J., H.G. LAREW, & D.F. MARION. 1987. Exotic neem seed extract battles birch leafminers. Am. Nurseryman 166(4): 149, 152, 154.

Chances are good that you have never heard of neem. It has recently come to the US from India, where it has been used in a variety of ways: as an insecticide and medicine and in religious rituals for centuries. Neem, (Azadirachta indica) grows in India, Africa, the Caribbean and Florid. It requires a frost-free climate, but it is surprisingly fast grower under a variety of conditions. Why all the interest in neem? In large part, it is because of the public’s cry for effective insecticides with low mammalian toxicity. Neem, although no panacea or cure-all, does kill and repel a wide variety of insects. And, as far as we know, it does so without the disruptive side effects and hazards of some synthetic pesticides. Most experiments with the extract have been conducted in laboratories under controlled conditions. We conducted the trial using paper birches in an infested commercial nursery in upstate New York. We found that, regardless of spraying time, the solution of 1 percent neem seed extract caused about as much leafminer death as did Metasystox-R. The test confirms that neem seed extract may have a place in future insect control programs in commercial nurseries.

• © 1988, International Society of Arboriculture. All rights reserved.