Yellow garden spiders are large, orb-weaving arachnids, meaning they spin a circular web. Most spiders have two claws on each foot, but orb weavers have an additional claw to help them spin their complex webs. In females, the top side of the abdomen is black with symmetrical patches of bright yellow. The legs are reddish brown at the base and black toward the tips. Males are less striking in appearance—they are smaller with brownish legs and less yellow coloration on their abdomens. Females average 0.75 to 1.1 inches (19 to 28 millimeters) in body length, which is up to three times larger than the males 😊 
Size: Adult female is about 1/2 inch long. Color: Adult females are glossy black with a variable number of red markings on the top and bottom of abdomen. Adults males are similar, but with a few white markings. Juveniles are highly variable.Features: Abdomen is nearly spherical on adult females and juveniles. Male is slimmer with longer legs (pictured here). Notes: Bites are very serious and require immediate medical attention, but the spider is timid and unlikely to bite unless handled. Black widows are common all over Kentucky. They tend to occur in concealed outdoor locations: piles of rocks, piles of firewood, and dark corners of garages and out-buildings. Females are common; males are very rarely encountered. 
Argiope aurantia is a showy spider usually noticed in late summer. It has several common names: black-and-yellow argiope, black and yellow garden spider, corn spider, golden garden spider; golden orb-weaver, writing spider, yellow garden argiope, yellow garden orb-weaver, and zipper spider. The bodies of females grow to a little more than one inch long; males are much smaller. The third pair of legs is about half as long as the other legs. Males often hold the front pairs of legs close and the hind pairs of legs close together so that the silhouette resembles a St. Andrew’s cross. The segment to which the legs and mouthparts attach is covered with very short, shiny, white scales. The abdomen is egg-shaped and conspicuously marked with black and yellow. Females spin orb webs (spiral sticky threads suspended on non-sticky spokes) with a conspicuous white zigzag structure in the middle called the stablementum. Spider experts disagree about why these spiders spin stablementa. Earlier the stablementum was thought to give stability to the web. Now the thinking is that the stablementum attracts insects or keeps birds from flying through the web. All spiders are carnivores that prey primarily on insects. Black and yellow garden spiders find their prey by sensing vibrations in the web. They eat anything that doesn’t tear itself loose from the web. At night, females consume the sticky strands of the web and spin new ones. It had is thought they gain some nutrition from minute insects and even miscellaneous organic matter caught in the web. After mating in late summer or early fall, females lay several hundred to a thousand or more eggs inside a brown, silk, spherical cocoon about an inch in diameter. The spiderlings hatch but do not emerge from the cocoon until the following spring. Unfortunately for them, parasites and predators, including birds, prey upon these hapless spiderlings so that only a few survive the winter and even fewer survive to become adults the following season. There is one generation per year. (nice one to Morena Robb for telling us). 
Yellow garden spiders are crepuscular (active during the morning and at nightfall) (Harwood 1974). Juveniles construct webs at night similar to adults, but second and third instars are slow to complete their webs, requiring two nights, rather than a typical single night (Enders 1977). Webs are typically attached to trees, shrubs, and herbaceous weeds; however, Lespedeza spp., or bush clover are a preferred attachment site (Enders 1997). Webs are primarily placed facing away from dense vegetation and angled downhill. Adults prefer to place their webs at high points on vegetation and in areas new to the spider, they exhibit questing behaviourr where they climb to the top of the vegetation and waving their front legs to survey the area. (credit goes to Celina Elmore for their recent revisions).