Peanut Update, Velvetbean Caterpillars

Here is another peanut update from Clemson Peanut Specialist Jay Chapin.

The 1.5 -2” of rain most areas got on 7 Aug. put us back in the ball game at least temporarily on dryland peanuts, but most of our southern peanut belt missed out on getting any follow up this week.  Some fields that had 1.5” on Friday were pretty dry in the pegging zone by Monday.  We need more to avoid going right back into stress.

I looked at a good many runners pods early this week and most had held up pretty well.  Not a surprise that the runners look better than Virginias under the same conditions.

How to Check Crop Potential

Pull up a clump of plants and pinch the pods with about the force you would use to crack a boiled peanut.  There’s no give in sound pods; they’re firm no matter whether they are full-sized or not.  Even a half-grown young white pod without the seed fully formed is firm to pressure.

If the pods were stressed, they give in.  Stressed full sized pods will either pop altogether or just give a little.  If they just give some, they might make an SMK, but they’re not full of meat, which affects both yield and grade.  Small stressed pods give in and often have a rubbery look and feel to them.

Mites

All of the mite calls I had last week were in fields that had been sprayed previously with pyrethroids. It can happen anywhere if it stays dry long enough, but pyrethroids raise the risk.

Start Checking  for Velvetbean Caterpillar Below the Lakes

Worm populations have been generally very light this year.  Velvetbean caterpillars might end up being the exception.  Velvetbean caterpillar moths showed up a bit early this year in our southern counties.  I was surprised to see moths last month even in Calhoun Co.  VBCs are almost an annual September / Oct. problem in Jasper, Hampton, Allendale, Colleton Co. soybeans.   It looks like they’ll get an earlier start this year which makes them more of a potential threat to peanuts.

IMG_20140924_152605_540

So far it is really spotty.  Nearly all the fields I have looked at have only 0-1 per row ft; it can change in a hurry though.  James Thomas found one small field with 6/ft as far north as Govan.  Everything else in the area had <1/ft.

We don’t play around with velvetbean caterpillars when we still have 40-50 days until digging.  It’s best to use a drop cloth to make sure you are not missing small “threads”.  We stick to the 4/ft threshold for velvetbean caterpillar even on rank growing fully closed canopies.  Even two med. – large VBC larvae/ft plus another two very small VBC/ft justifies treatment when a fungicide application is being made.

Pyrethroids still provide economical control of VBC, but make sure there is a significant risk of defoliation before increasing spider mite risk.

Click here for the Clemson Peanut Production Guide.

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