Find It Here
Twitter update
Subscribe

Subscribe to Post Updates from Arkansas Row Crops


 

RSS AgNews
Quick Links
Agricultural Programs
08
May
2012
High insect numbers are cause for concern
Author: Gus Lorenz, Extension Entomologist

Insects numbers are extremely high for this time of year.  We started running moth traps 3 weeks ago for bollworm in Lonoke County. The first week, the numbers were high for this time of year but not alarming, averaging about 20 moths per trap. The second week numbers increased to about 30 moths per trap for the week. Again, high but not alarming. Last week the traps jumped to over 300 moths per trap. That is an increase of over 10X from the previous week. These kind of numbers usually aren’t seen until the end of May or first of June confirming the fact that like our crop the insects are about a month ahead of schedule. Those moths are laying eggs somewhere.  We advise to start scouting corn, particularly refuge corn, seedling soybeans, milo, tomatoes, etc. for developing populations.

Soybeans

Along with the bollworms, we are also getting reports of fall armyworm, yellowstriped armyworm and garden webworm beginning to show up in seedling soybeans. With all of this caterpillar activity, what do you do if you see developing populations in your field?  I would be really hesitant to spray a pyrethroid for fear of wiping out the beneficial insect population. Certainly the pyrethroids are cheaper, and they should be effective, particularly on the armyworms and webworms, but the impact on the beneficials may end up costing more in the long run. That’s what happened last year with the Yellowstriped Armyworm outbreak.  Growers who sprayed with a pyrethroid ended up having more of a problem with bollworm later on. Alternatives include Intrepid or Tracer. Both of these products may cost a little more but are much easier on beneficial insects, which we are going to need before the year is over. Food for thought.

Also, we are getting a lot of calls about grasshoppers on field edges beginning to build. One of the most effective treatments we have seen this time of year while the grasshoppers are still small is 2 oz of Dimilin per acre plus crop oil.  It can be sprayed on the crop or on the field edges. It is extremely safe, cost effective and it is soft on beneficials.  Just remember the bigger the grasshopper, the harder it is to control, so now is the time to take action.

Cotton

Thrips numbers appear to be high this year, and some of the early planted cotton that has been planted a while is beginning to show some wear and tear from thrips. Like Louisiana, we are seeing a lot of western flower thrips out there and as you would expect, control with orthene and bidrin has not been real good. I have had several reports of thrips behind both treatments. Probably one of the better options is a new product called Radiant. It goes out at 1.5 oz/ A + crop oil. The crop oil is critical to achieve control. We have already received feedback on this product without crop oil not achieving control, so if you plan to use the product , be advised the crop oil is essential in getting the desired control.

Rice

There is not a lot going on in rice at the moment.  The armyworm plague seems to be winding up for Arkansas. We are seeing chinch bugs in some areas, so I would advise scouting field edges closely for this pest. They are out and about as we were picking them up around Pine Tree last week, landing on the side of the pick-up truck, so I know they are moving around looking for hosts right now. Also, the fall armyworms are around, so keep an eye out for them.

Summary

I don’t know what to think about the bollworm moths and where they might end up, but I would be checking corn and small soybeans right now to see if they will end up in those crops.  We should know by the end of the week or first of next week. This is building up to be a bad year. Hang on, this one may be a doozy.


Save pagePDF pageEmail pagePrint page
«
»