Nocturnal Activity and Movement of Black Cutworms (Lepidoptera: Noctuidae) and Response to Cultural Manipulations on Golf Course Putting Greens

Abstract

Nocturnal activity, feeding behavior, and movement of black cutworms, Agrotis ipsilon (Hufnagel), and responses of larvae to cultural manipulations were evaluated on creeping bentgrass, Agrostis palustris Hudson, golf putting greens. Larvae were active throughout most of the night with the greatest activity between midnight and ≈1 h before sunrise. Small larvae (3rd and 4th instars) were active on the surface of putting greens, whereas large larvae (5th and 6th instars) fed mainly from burrows or tunnels in the putting green surface. Larval tracks in the dew averaged 8.8 ± 0.7 m, indicating that A. ipsilon can move considerable distances on putting greens in a single night. Many larval tracks originated from the peripheral area, suggesting that some larvae found on putting greens originate from higher-mowed turf surrounding the green. Contrary to the common belief of golf course superintendents, A. ipsilon larvae were not attracted to aerified over nonaerified turf. However, most larvae occupied aerification holes as burrows when such holes were available. Topdressing with 100% silicas and or a silica sand/peat moss mix did not affect survival of cutworms in creeping bentgrass turf cores. Nevertheless, larvae tended to avoid putting green surfaces topdressed with sand. Manipulating the timing of topdressing may be one method of reducing cutworm populations on putting greens.