–by Jeff Whitworth — Field Crops, Entomology
Grasshopper eggs, deposited last fall, have been producing small nymphs for about the past 2 weeks. Thus, if field borders, weedy ditches, or any non-disturbed areas adjacent to crop fields are infested with these small nymphs- it is an ideal time to treat these areas to get good control (see fig 3).
Figure 3. Grasshopper nymphs
–by Jeff Whitworth — Field Crops, Entomology
The 1st potato leafhoppers were detected in northcentral Kansas on 10 June, but probably started immigrating in a few days prior to that. They will continue this immigration for about another month. As of 14 June, however, only adults were active (see fig 1) but they are depositing eggs which hatch into very tiny nymphs in approximately 4-7 days. Much alfalfa, however, has just been swathed, or soon will be, and this will help mitigate potato leafhopper damage by removing eggs/nymphs before they cause any damage (see fig 2-often called “hopper burn”). However, adults will continue to migrate into these fields- so monitoring should continue as the new growth emerges.
Figure 1. Adult potato leafhoppers
Figure 2. Hopper burn
–by Sharon Schroll
–by Jeff Whitworth — Field Crops, Entomology
Just FYI: Kansas State University and the Department of Entomology are super proud to announce that starting with this fall semester there is a new undergraduate degree available in Entomology. Thus, KSU and Entomology are now offering a Bachelor’s Degree in Entomology. Previously, only Master’s and Doctor of Philosophy degrees were offered by KSU’s Entomology Department, which historically has been one of the top rated departments for research and academics. If interested in Entomology’s Bachelor degree program please contact Dr. Brian McCormack, Department Head, or Dr. Jeremy Marshall, Undergraduate Coordinator.
–by Raymond Cloyd, Horticultural Entomologist
We have received numerous inquiries associated with insects feeding on the leaves of rose plants. The insects are sawflies and there are at least two species that attack roses this time of year: the rose slug, Endelomyia aethiops, and the bristly rose slug, Cladius difformis. Rose slugs are the immature or larval stage that eventually becomes a black to yellow-colored adult, which resembles a wasp.
Rose sawfly females create openings or slits along the edges of rose leaves with their saw-like egg laying device (ovipositor) and insert eggs. Larvae emerge from the eggs and resemble small slugs. Larvae are approximately 1/2 of an inch long when full-grown and yellow-green, with an orange head (Figure 1).
Figure 1. Rose Sawfly Larvae Feeding on Rose Leaf (Raymond Cloyd, Kansas State University)
The larvae fall onto the soil surface and pupate. Rose slugs overwinter as pupae in earthen cells that are created by the larvae. Bristly rose slug larvae are pale-green and approximately 1/2 to 3/4 of an inch in length. The body is covered with bristle-like hairs (Figure 2). Both species typically have one generation per year in Kansas.
Figure 2. Bristly Rose Slug Larva Feeding On Leaf Underside of Rose (Raymond Cloyd, Kansas State University)
Rose slug larvae feed on the underside of rose leaves causing the leaves to appear skeletonized (Figures 3 and 4). The larvae create notches or holes on the leaf margins. Bristly rose slug larvae feed on the underside of rose leaves causing leaves to appear skeletonized. However, the larvae create larger holes than the rose slug.
Figure 3. Damage on Rose Plant Caused By Rose Slug Larvae Feeding (Raymond Cloyd, Kansas State University
Figure 4. Damage on Rose Leaf Caused By Rose Slug Larvae Feeding (Author-Raymond Cloyd, Kansas State University)
Small infestations of either the rose sawfly or bristly rose slug can be dealt with by removing the larvae by hand and placing into a container of soapy water. A high pressure water spray will quickly dislodge sawfly larvae from rose plants and they will not crawl back onto rose plants. There are a number of contact insecticides containing various active ingredients that are effective in managing populations of both sawflies. Sawflies are not caterpillars. Consequently, the bacterium, Bacillus thuringiensis subsp. kurstaki, which is the active ingredient in various products (e.g. Dipel®) has no activity on sawflies because the insecticide is only effective against caterpillars.
–by Sharon Schroll
It turned over a new leaf.
–by Frannie Miller, Pesticide Safety & IPM Coordinator
The Kansas State Pesticide Safety and Integrated Pest Management program is excited to announce the availability of our “Wacky Entomologist” card game. The cards feature art created by Kansas youth selected from the 2020 Insect Art Contest winners. We truly have some talented artists in the state of Kansas, and this is a unique way to highlight their art. The game is like “Old Maid,” but the objective is to help the “Wacky Entomologist” match all the insects and not get stuck holding the spider. This resource would be great for summer camps, preschool teachers, art lovers and anyone who has insect-loving youth. The cards can be purchased for $10.00 at: commerce.cashnet.com/IPMKSU.
–by Jeff Whitworth, Field Crops – Entomology
I have received a few calls within the last 10 days about “Miller moths” flying around lights at night and flying/running into the house when an outside door is opened the 1st thing in the morning. Those, at least from my experience and the specimens I have seen, are adult army cutworms (see pictures by Cayden Wyckoff). Like most adult cutworms, the army cutworm is a relatively thick bodied but otherwise nondescript moth. These moths are even more nondescript after losing wing scales while flying and/or hiding under objects during the day. They are a relatively agile, quick moving moth, and in Kansas always seem to be present just before and/or during Memorial weekend. As far as crops go, the army cutworm feeds on wheat or alfalfa since those were the crops growing last fall when the female moth was depositing eggs. Thus, since last fall the larvae have fed all winter and spring, pupated, emerged as adults, and are/or have headed for over- summering sites, usually somewhere in the Rocky Mountains. These same moths then, at least the ones that survive the summer, will be heading back this way in late summer or early fall and depositing eggs in wheat and alfalfa fields along the way. After depositing their eggs, these adult moths expire, but have started the next generation.
Adult army cutworm
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