Summary Cutworm damaging is still showing up in some fields. A few fields have had foliar insecticide applications to manage flea beetles, but overall populations are not high this year. Recent Insects of Concern Cutworms Recent Observations: Cutworms were reported to be causing substantial damage to some fields in the Elgin area. A canola field in the area is being reseeded due to cutworm damage, and a corn field in the area also has had substantial damage. Heavy cutworm populations have also been reported around Grosse Isle, Oak Bluff, Brunkild and Arnaud. Scouting Tips: If you are seeing leaf feeding but very little stem cutting, this could still be cutworms. Some of the species of cutworms, such as the redbacked and dingy cutworms that seem to be quite numerous this year, will spend a lot of time aboveground on the plants feeding in the evening. During the day you will see the feeding they have done, but not the cutworms. Dig around the damaged plants to determine if cutworms are the cause. Management Tips: Some of the damage that was reported this week was patches of cutworm damage within a field. A reminder that controlling cutworms in infested patches is sometimes an option, and spraying whole fields is not always the most economical method of control. When deciding whether cutworm control would be economical, consider the stage of the cutworms. Some species that overwinter as larvae, such as dingy or army cutworms, may be fully grown larvae or starting to pupate already. If this is the case, control is not likely to prevent enough yield loss to make it economical. In most species of cutworms, the larvae will get to about 3.5 to 4.0 cm (about 1.5 inches) before they turn into pupae and are finished as the potentially damaging stage. Flea Beetles on Canola Recent Reports and Observations: Some foliar spraying to manage flea beetle populations occurred near Miami and Lowe Farm. Observations from traps we have out for flea beetles in 6 fields are that overall populations are light, and crucifer flea beetle is the dominant species in canola fields.

Seedcorn Maggot in Soybeans Recent Reports and Observations: Seedcorn maggot caused significant damage to about 80 acres of a 160 acre soybean field near Elie. The damaged area will be reseeded. Management Tip: Seedcorn maggot is another early season insect that can not be controlled with foliar insecticides, although seed treatments are available that will provide control.	Seedcorn maggot in beans
Aphids on Cereals Recent Reports and Observations: English grain aphids were found recently in a winter wheat field near Brunkild. They were not in very high numbers, but it may be good to start looking for aphids when scouting cereal fields. English grain aphid is not known to overwinter here, but gets moved into Manitoba on winds from the south.	English grain aphids on winter wheat

Cereal Disease Risk

The risk of infection from Fusarium head blight (FHB) in winter wheat that is heading and soon to flower, based on gut feel, is . . . HIGH. Recent rains in southern Manitoba have ensured that most soil are at field capacity or saturated. Coupled with a sudden increase in both daytime high and nighttime low temperatures means we are experiencing prolonged periods of high humidity. The ideal conditions for FHB infection to occur are temperatures between 15 and 30C and humidity above 85%. These are the factors we use in the model to predict risk of infection. Our intention is to have color maps posted by the end of this week and to continue daily through July.

Leaf rust has now been seen on spring wheat and powdery mildew is beginning to appear on winter wheat east of the Red River.

Surveys and Forecasts

Bertha Armyworm Forecasting: For those involved in setting up traps to monitor adults of the bertha armyworm, this week would be an appropriate time to get the traps set up. Counts from these traps will forecast the risk from larvae later in the season. Protocols for setting up the traps can be found at:

• http://www.gov.mb.ca/agriculture/crops/insects/fad59s00.html

Diamondback Moth: Traps counts have been coming in since the week of May 20 – 26, and so far counts have been low; the highest count so far is 13 from a trap near Altona.

Wireworm Survey: A reminder that a survey of the species of wireworms is being conducted across western Canada. The purpose is to determine the dominant species of wireworms in different regions. Wireworms is a term that refers to the larvae of a family of beetles known as click beetles, of which there are many species. Knowing the dominant species of wireworms in a region could have implication for how they are managed.

How to Send Wireworm Samples: When you send wireworms, you can send them live, in a small container with soil. An ideal container is a film roll canister (if you still have some of these) although any container will do as long as it will not break or open in transit. You can put a few wireworms in a container filled with soil, but some species do eat each other, so I wouldn’t put more than 5 in a container. There is no need to put holes in the lids for air, or to moisten the soil; just send them in whatever soil they were found in, as it provides an idea of what soils they prefer.

Where to Send Samples: The entomologists doing the identification are based in Agassiz, B.C. Samples can be sent to Dr. Bob Vernon, Pacific Agri-Food Research Centre, P.O. Box 1000, 6947-#7 Highway, Agassiz, BC V0M 1A0. If it is more convenient, samples can be dropped off at the nearest MAFRI office or to me, and I can send them in with samples I will be submitting. If you are aware of fields with high levels but have not collected any, please let me know and I can try to have some collected.

Insect Identification Quiz

Question: While field scouting last week, I took some water samples from a ditch where stagnant water seems to sit for quite awhile after a rain, to see what may be living there. The insect in both of these photos was very abundant in this water. What are they?

Hints: The insects seen in photo A were generally anywhere from a couple of millimeters to about a 7-8 mm long. The insect in photo B may be somewhat tadpole-like in shape, but are much smaller.

Answer: The picture on the left is mosquito larvae, the picture on the right is a mosquito pupa. These can only live in water; our most abundant species like water that is not moving. In the ditch I was sampling I was finding about 20 or 30 every time I dipped my sampling container in; i.e. the ditch was full of them. Although there was still more larvae then pupae, there will likely be a lot of adults coming out of that ditch soon.