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Department of Agronomy

Kansas State University

1712 Claflin Rd.

2004 Throckmorton PSC

Manhatan, KS 66506

785-532-6101

agronomy@ksu.edu

Extension Agronomy

Late-fall insect pest update

Wheat pests

Fall armyworms and armyworms are still active in wheat and can be for another month, depending upon the weather. If growing conditions are good, the wheat should be able to outgrow feeding damage caused by small worms. Large worms have probably caused most of their feeding damage already, and hopefully won’t be able to pupate, emerge as adults, lay eggs, and have those eggs hatch again this fall.

Winter grain mites may cause some concern in the next month or so, especially under dry conditions. However, insecticide applications are rarely warranted and these mites seldom impact wheat yields. As with worms, good growing conditions for wheat will mitigate winter grain mite feeding damage.

Sugarcane aphids

Sugarcane aphids were still active in north central Kansas based on our observations on October 23 and 27, as were the beneficial insects (see photos below). Fields were being harvested and growers were getting acceptable yields. Growers reported yields of 80 to 160 bu/acre -- which they said was usual for the fields involved -- without much interference caused by the stickiness of the honeydew (and it is sticky).

Figure 1. Photo by Holly Schwarting, K-State Research and Extension.

Figure 2. Photo by Holly Schwarting, K-State Research and Extension.

 

Figure 3. Photos by Holly Schwarting, K-State Research and Extension.

 

Below are the results of 2015 sugarcane aphid efficacy trials conducted in Saline Co. Aphid populations were, in our opinion, ideal for conducting trials of this nature because there were enough aphids to show any differences caused by the treatments, but not so many that the plants were overwhelmed or that the grower had to spray the entire field (thereby over-spraying these plots).

 

Means within a column followed by the same letter are not significantly different (P>0.05; PROC ANOVA; Mean comparison by LSD [SAS Institute 2003]).

 

Means within a column followed by the same letter are not significantly different (P>0.05; PROC ANOVA; Mean comparison by LSD [SAS Institute 2003]).

 

Jeff Whitworth, Extension Entomology
jwhitwor@ksu.edu                                                         

Holly Schwarting, Research Associate, Entomology
holly3@ksu.edu

J.R. Ewing, Graduate Student, Entomology
jrewing@ksu.edu