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News, events, and happenings in Colquitt County agriculture.

I’ve been getting more and more reports of damage from Bermudagrass Stem Maggot (BSM). I recently spoke with our forage specialist, Dr. Dennis Hancock, who says that damage in south GA has been heavy this year.

BSM is a recently introduced pest that was noticed in our area in the summer of 2010. The damage caused by BSM causes the field to have a frosted appearance.


The larval stage (maggot) of a fly is responsible for the damage. As you can see, both are really small.



The larva feeds just above the last node at the top of the plant causing the top 2-3 leaves to die which could mean loss in yield.


Damage is worse when growth is limited by poor soil and moisture conditions, especially in coarse varieties like Tifton-85 even though all varieties are attacked. Grazed pastures are not usually affected by BSM because the animals eat the eggs and larva while grazing, reducing populations. However, significant damage can be observed in sparsely grazed pastures.

Harvest management is one of the most effective ways to reduce losses. If damage occurs within 1 week of harvest, proceed as planned. Yield loss at this point will be minimal. If damage occurs within 1-3 weeks after the previous harvest, the crop is not likely to produce more tonnage. Go ahead and cut and harvest if economical. Removing the cut hay is important in promoting rapid regrowth. Hay left in the field will only reduce the rate of growth for the subsequent crop, potentially resulting in more yield loss should BSM infestations reoccur. In heavy infestations, spraying the lowest rate of a labeled pyrethroid within a few days after harvest and once more 5-7 days later will provide acceptable control.

Contact me for more information or a customized recommendation for your situation.



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