Secondary stress. A secondary stress is any stress in the structure which is not a primary stress or peak stress. Source: API SPEC 16R, Specification for Marine Drilling Riser Couplings, Exploration and Production Department, First Edition, January 1997. Global Standards.
Two groups of ground nesting bees commonly. found in Michigan are bumble bees and. burrower (andrenid) bees. Bumble bees are. easily recognized by their large, robust, hairy, black and yellow (sometimes orange) bodies. Bumble bees live in colonies of several. hundred individuals, but only the queens.
Variances in Appearance. Carpenter bees, species in the genus Xylocopa, and bumblebees, members of the genus Bombus, are both large, fuzzy bees, and they are often mistaken for one another in a garden. The easiest way to tell the difference between a carpenter bee and a bumblebee is to look at the bee's abdomen. The carpenter bee's abdomen is shiny, black and devoid of hairs on its upper surface. A bumblebee's abdomen is hairy and usually has yellow markings.