Eggs overwinter in stems of iris and other debris. After eggs hatch they must crawl to the base of the iris to bore into stems. Infested leaves are yellow from the tip back, have notches on the edge; plants lose vigor; many fail to bloom.
Nema-Ject™ Nematodes are the only effective control. During the migration of larva from base of plant into stems, they are susceptible to Nema-Ject Nematodes. Soak the bottom portion of stem and soil. Keep soil moist for first week.
"My iris plants have come back to life and look healthy after using nematodes for borers. I'll need more for other uses next spring!" -B. Thumler, Huntingdon Valley, PA