There are many different forms of ladybugs, from solid black to solid yellow or orange, from those with no spots on their wings to those with a couple dozen black spots, from very small species to some nearly 1/2 inch long. The larvae are often misunderstood and misidentified by people who believe they must be a plant feeding bug, but the larvae too are voracious predators that can clear a patch of aphids very quickly. They are usually a patchwork of red and gray spots and are described as "those tiny alligators". When they pupate they attach to the trunk of the tree, side of a building, or any other convenient hard surface. 

There is one species that is a concern to plant health, and that is a yellowish species called the Mexican Bean Beetle. It is widespread in the eastern U.S. and in Mexico, generally occurring east of the Rocky Mountains, so it's possible this could occur in your area in Oklahoma. True to its name it feeds almost exclusively on legumes of many kinds, so if this vegetable garden is growing beans or peas then this beetle might be a problem. If so, a contact insecticide labeled for use on vegetables would be effective in killing them when the larvae first appear. 

But, given that this family of hundreds of species has only a couple of plant damaging species in it, and the rest are highly beneficial as predators, the likelihood is that the ones you are seeing are some of the good guys and should be encouraged rather than killed.