Weeds are one of the main limiting factors in crop production, causing billions of dollars in annual global losses through degraded agricultural and silvicultural productivity. Weeds also reduce access to land and water, impair aesthetics, and disrupt human activities and well-being. The number of positions devoted to weed science teaching, research, and extension at 76 land-grant institutions across the United States and its territories was determined and compared with that for plant pathology and entomology. The number of classes and graduate students in these disciplines at those institutions was also determined. There are more than four times as many entomologists and more than three times as many plant pathologists as weed scientists at land-grant institutions. There are approximately five times as many graduate students currently in entomology and almost three times as many in plant pathology compared with weed science. There are approximately five times as many entomology and two and a half times as many plant pathology undergraduate classes compared with weed science classes. These differences increase when graduate courses are considered. Most land-grant universities have either none or few graduate classes in weed science. There are more than six times as many graduate entomology courses and more than five times as many plant pathology courses compared with weed science graduate classes. There are no departments devoted solely to weed science, whereas entomology and plant pathology departments are both common. Most universities have little to no faculty assigned to ornamental, fruit, aquatic, or forestry weed control. Number of faculty assigned to vegetable, turf, non-crop, ecology, and basic/laboratory studies in weed science are also limited. Additional university resources are needed if weed science research, teaching, and extension efforts are to meet the priority needs for the management of weeds in the agricultural, natural resources, and urban ecosystems.