–by Frannie Miller
Colorado potato beetle – The pictured insect is identified as a Colorado potato beetle. Both the larval and adult stages feed on potato (sometimes tomato, eggplant and pepper) causing extensive foliage loss, which can lead to decreased yields.
–by Frannie Miller
–by Dr. Jeff Whitworth
How do fleas travel?
They “itch” hike.
–by Dr. Jeff Whitworth
We have received several calls relative to false chinch bugs (fig. 5) damage to soybeans. In most cases false chinch bugs may appear in large numbers in a patch or two in a field, and usually after the soybean field was treated with a herbicide. The most common natural host of false chinch bugs are plants in the mustard family. So when these are killed by a herbicide, the false chinch bugs congregate and may feed for a few days before dispersing. This feeding, by removal of plant juices, usually has little to no effect upon the plants, but occasionally can be very detrimental to soybeans (fig. 6) and sometimes sorghum.
Figure 5: False Chinchbug
Figure 6: Soybeans affected by False Chinchbugs (photos provided by Rod Schaub)
–by Dr. Jeff Whitworth
The first adult western corn rootworms (WCRW) (fig. 1) were detected on 5 July, 2020, in north central Kansas. Since this first emergence there has been considerably more emergence, to the point that there are several areas of north central Kansas that are now concerned about silk clippings by these adults. WCRW adults spend much of their time in the early morning, and then again toward evening, feeding on silks (fig. 2)—thus, shown here in a position that they are commonly found in while feeding on silks. They may spend much of the middle, warmer, part of the day in more shaded areas, i.e., behind leaf collars, etc. Figure 3 shows typical “goosenecking”, from the previous root feeding, which is now completed, by the larval stage of the WCRW.
Figure 1: Adult Western Corn Rootworm (WCRW) ( Cody Wyckoff)
Figure 2: WCRW in position that they are commonly found while feeding on silk (Cody Wyckoff)
Figure 3: Goosenecked corn (Cody Wyckoff)
There is also much corn earworm and fall armyworm activity in corn fields that are just now, and have just recently, started silking. The larvae (fig. 4) observed around north central Kansas will probably feed for about another 2 weeks, then, pupate in the soil, emerge as adults which mate, and start depositing eggs. These eggs will most likely be deposited in late planted corn, or sorghum (between flowering and soft dough) and/ or soybeans.
Figure 4: Larva feeding on corn (Cody Wyckoff)
–by Frannie Miller
Rough stink Bug – As you can see from the image, Rough stink bugs resemble the color and texture of a tree’s bark providing them with camouflage. These insects feed on caterpillars, planting eating beetle larvae, aphids and other soft-bodied insects that may harm plants.
–by Dr. Raymond Cloyd
Squash vine borer, Melitta curcurbitae, feeds on squash, pumpkin, cucumber, and muskmelon. At this time of year, larvae are feeding inside plants. Adults are moths that are 5/8 inches long, orange-red, with gray bands and three to four black markings along with orange-red hairs on the abdomen (Figure 1).
Figure 1. Squash Vine Borer Adult
). Adults are active during the day with females depositing eggs on the stem near the soil level or on stems or petioles when plants begin to flower. The eggs are red-brown, flattened, 1/30 inches in diameter, and are located at the base of plants (Figure 2).
Figure 2. Squash Vine Borer Eggs At Base Of Plant
A single female can lay up to 200 eggs during her lifetime. Larvae that emerge (eclose) from eggs are white, with a dark head capsule. Young larvae are 1/4 to 3/4 inches in length and taper toward the end of the abdomen. Mature or fully-grown larvae are 1 to 1-1/2 inches long (Figure 3).
Figure 3. Mature Squash Vine Borer Larva (Raymond Cloyd, KS)
Larvae that emerge (eclose) from eggs immediately tunnel into the base of plants; feeding for 30 days in the plant stem. The larvae increase in size as they mature. There is usually only one larva per stem; however, multiple larvae may be present in a single stem. In fact, one year we found seven larvae in one stem (it was awesome J). Mature larvae emerge from plant stems and burrow into the soil. The larvae construct brown, silken cocoons where they overwinter. Squash vine borer overwinters as a mature larva in the cocoon located 1.0 to 2.0 inches deep in the soil. In early spring, adults emerge from the soil. Squash vine borer has one generation in Kansas.
During this time of year, squash vine borer larvae are feeding within the internal vascular tissues, which inhibits the plant’s ability to take-up water and nutrients. Consequently, larval feeding causes the sudden wilting of vines and plant collapse (Figure 4).
Figure 4. Plant Wilting Due To Feeding By Squash Vine Borer Larvae (Raymond Cloyd, KSU)
Once the larvae are inside the plant, not much can be done to manage squash vine borer and prevent damage. The tunnels inside infested plants are filled with moistened frass (fecal matter) (Figure 5).
Figure 5. Frass Associated With Squash Vine Borer Larva In Plant Stem (Raymond Cloyd, KSU)
Yellow-green sawdust-like frass can also be found around feeding sites at the base of vines or plants, which will be a direct indication that larvae have entered the plant.
Since the larvae are feeding inside the plant there is not much that can be done to kill the larvae; however, there are plant protection strategies that can be implemented during the remainder of the growing season such as; sanitation and physical control.
Sanitation: remove and dispose of all wilted plants before the larvae leave and enter the soil. Discard all plant debris such as vines and fruits after harvest.
Physical control: rototilling in fall will directly kill squash vine borer pupae or bring the pupae to the soil surface where they are exposed to cold weather or predation by birds. In addition, the process of deep plowing will bury the pupae deeper in the soil profile, which may inhibit adult emergence from the soil. Another technique that may have limited use in large plantings but may be feasible for smaller plantings is to locate infested stems and vines, and create slits at the base of the plant. Tweezers can then be used to remove larvae from inside the plant. Larvae should be killed and the plant base covered with moist soil and mulch, which will stimulate the production of secondary vines and/or root growth; thus helping the plant to re-establish.
For more information on how to manage the squash vine borer, refer to the following extension publication:
Squash Vine Borer (MF3309 July 2016)
http://www.bookstore.ksre.ksu.edu/pubs/MF3309.pdf
–by Frannie Miller
–by Frannie Miller
Picture-winged fly – Picture-winged flies get their name from the distinct ornate color patterns on their wings. It is almost like they are painted. Their body shape kind of reminds you of an ant. Larvae feed on rotten, decomposing vegetation and rotten fruit. These insects can be confused with fruit flies, but do not feed on living plant matter like fruit flies.
–by Frannie Miller
This week as I have been out in my own yard and garden I have noticed an abundance of different types of caterpillars. Identification of caterpillars can be difficult because so many of them look really similar, but often if you know what plant they feed upon it will give you a clue.
The first image is of a caterpillar sent to me by a friend asking what it was. She found it feeding on her pansies, which were a hold over plants from spring. These caterpillars are known as pansyworms. They usually grow to be 1 ¼ inches long with a characteristic deep-orange color with black striped sides which feature spines. These caterpillars will take bites out of the leaves, but the resulting variegated fritillary butterfly will add color to the garden.
Panysworm image: Courtesy of Cheryl Boyer
Then I found a few yellowstriped armyworm caterpillars feeding on some of my flowers. I picked them off as I did not want them to feed on those particular plants, but allowed them to feed elsewhere. These caterpillars turn into a somewhat drab grayish-brown moth.
Yellow Striped Armyworm
Finally I spotted a mass of small caterpillars feeding on sunflowers in the garden. The sunflowers were not ones I plants and had come up as volunteer so I have decided to let the caterpillars eat on these plants. It is difficult to for me to identify the exact species from a picture, but they will turn into some sort of checkerspot butterfly.
I have chosen to not use any insecticides to control these particular caterpillars, but options such as Bacillus thuringiensis subsp. kurstaki (Btk) and spinosad can be used when caterpillars are small. If you are going to use these products, remember to read and follow the label.
Checkerspot Caterpillar
Sometimes we don’t notice the caterpillars until they are larger and hand picking may become the best control option.
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