Trap Catches Identified to August 10th
Greetings!
We recovered a total of 301 aphids, 263 of which were vector species. In terms of aphid species, we are continuing to see a high diversity among those captured. This week, we recovered total of 15 different aphid species from 14 of the 16 sites reporting. We are seeing our heaviest flights in Grenora (80), Crookston (37), and Perham (36).
Last week, we recovered 130 total aphids, with the week before that topping off at 55 total aphids. Based on this trend, each week we are doubling the number of captured aphids. We saw this same trend occurring last summer towards the end of July to mid August, including a spike in cereal aphids. This does make sense, however, due to the maturing of grain which will lead to aphids seeking out better suited host plants.
We also recovered 2 Green Peach Aphids, one from Nebraska and one from Tappen. Other aphid species captured included English Grain, Potato, Bird Cherry Oat, Pea, Buckthorn, Corn Leaf, Turnip, Greenbug, Thistle, Cowpea, Blackbean, Sunflower and Foxglove aphids. Soybean aphids were captured at Crookston (1), Nebraska (1), Perham (7), Sabin (1) and Staples (2) - so we're continuing to see movement across a broad area.
Josie noticed more winged aphids landing on her in the field, so had an idea that this week we'd see an increase in aphid numbers. This time of the year, there can be large flights coming into a field in search of better host plants, so population numbers can greatly increase in a matter of days. Some of our vector species, like Soybean aphids, don't colonize potatoes (deposit daughters on plants), so actually finding an aphid on a plant is rare compared to often a winged aphid may actually be visiting plants in the field (an advantage of suction traps, sucks 'em up as they're passing!) Finding non-colonizing winged aphids on plants generally indicates there's a lot of movement going on.
As always, keep on scouting!
Cumulative PVY Vector Risk Index Map to August 10th, 2018
Cumulative PVY Vector Risk Index Map for 2017
(included for comparison)
Aphid Species Capture + PVY Risk - Week of August 5th, 2018
Total PVY Risk and Species Capture to August 10th, 2018
