Flour Beetles are the most significant pest of tree nuts, post-harvest.
There are two similar species we call Flour Beetles, the Red Flour Beetle and the confused Flour Beetle. These tiny beetles are about 1/8 inch long and are found all around the world. For the most part, the beetles are so similar that we don't differentiate them. However, there is one significant difference: RFB can fly, CFB cannot. In my long career, I never observed one fly (that I know of) until last year while working at a facility where I experienced swarms of flight all warm season.
Flour Beetles prefer eating the fine materials of the nuts. We typically find them more in the processing equipment and structure of facilities rather than in stored foods. If the facility piles hulls outside, they typically become infested near the end of the year before it gets cold. If the piles remain on the property when Spring comes, they will be a main source of beetle infestation in the facility. In addition, the huller/sheller if not cleaned at the end of season will provide plenty of beetles to the rest of the facility.
Controlling Flour Beetles is a major challenge. It takes a thorough strategic plan utilizing data analytics, a great service team and a dedication by the facility management to do what's necessary.
Battling these and other pests on the front line is what we do every day to protect the world's tree nut supply, and we are proud to do it.