The phone calls have picked up over the past week. Plant bugs have picked back up in some spots and in some areas of south Alabama they are still heavy. I spoke with one person in south Alabama yesterday about the insect situation in his area. He told me most folks are saying vigilant but getting frustrated with the number of plant bug applications going out. When asked about stink bugs, his response was “I think they all just morphed into plant bugs.” While that was a joke, it does bring up a point about stink bugs. We still just haven’t found many and still don’t understand why.
Plant Bugs
Plant bugs continue to dominate the situation, and a lot of
calls have revolved around Diamond. This insect growth regulator helps to keep
immature plant bug populations suppressed with good residual and rainfastness.
Diamond is best used when applied at the first appearance of nymphs, but that
doesn’t mean its ineffective at other times in the season. Right now, Diamond
can still be a big help in keeping populations in check. We have received
several calls this week about finding threshold populations of plant bugs 5 or
6 days after an application. Once we get embedded populations of plant bug
nymphs, it can take up to 10 days to really see the effects of Diamond. That
does not mean that I would not make a follow-up application in less than 10 days,
but I would not reapply Diamond in less than 14 (6 oz) or 21 (9 oz) days.
Stink Bugs
Populations are still low, but we have reached thresholds of
internal boll injury on the research farm in Prattville this week. Keep
scouting and monitoring fields. If possible, try to get a stink bug material in
the tank (Bidrin, Acephate, pyrethroids) when making plant bug sprays.
Spider Mites
We have received reports of spider mites requiring
treatments in SE and Central Alabama this week. Reports from NE Alabama are
that populations have held steady from last week and are bordering treatment
levels in some fields. At this point in the season we have a few options (Portal,
Zeal, Oberon) but abamectin (Agri-Mek and others) is the most economical
option. There are two formulations of abamectin sold (0.15 and 0.7), regardless
of the formulation, we should be on the higher end of the rate form this point
forward. As cotton gets more growth, higher rates tend to provide better
control.
Bollworm Flight
Our bollworm moth traps have picked up statewide in the past
week. We have heard some reports of heavy egg lay and a few fields with escape
worms requiring treatments in two-gene cotton. With the amount of VIP (3-gene)
cotton we have now, we shouldn’t be too concerned with bollworms but we should
be alert in the 2-gene varieties.
Soybeans and Peanuts
Calls for beans and peanuts are still far and few between.
We have been alerted of soybean field at threshold for soybean loopers in the
FL panhandle, but overall populations are just starting to build. Stink bugs
have still not been high in most fields. Hopefully the early beans will get away
without needing treatments. Later soybeans tend to be at higher risk so
continue scouting and monitoring.
As always, if we can ever be of any help, or if you would like to
provide input on the situation in your area, please don’t hesitate to reach out
(Scott Graham: 662-809-3368; Ron Smith: 334-332-9501). For more information on
thresholds and insecticide recommendations, visit the Alabama Cotton IPM Guide
(IPM-0415). To
stay up-to-date on the Alabama cotton insect situation, subscribe to the
Alabama Cotton Shorts Newsletter, Alabama
Crops Report Newsletter, and the
Syngenta Pest Patrol Hotline.
