Lateral roots are essential to young cotton plants for acquisition of water and nutrients. Lateral root development in the surface soil could be critical for survival of young cotton [Gossypium hirsutum (L.)] plants in semi-arid environmental conditions. On the Texas High Plains, where evaporative demand is fairly high, the more root surface area a seedling has, the greater its water absorbing capability and the less chance for growth-reducing tissue water stress to occur. Herbicides, such as trifluralin(Treflan),2,6-dinitro-N,N-dipropyl 4(trifluoromethyl)benzen-amine and pendimethalin(Prowl),N-(1-ethylpropyl)-3,4-dimethyl-2,6 dinitrobezeneamine are commonly used to control the weeds in cotton fields. The objectives of this research were to determine if herbicide source and /or rate will effect lateral root depth and cotton plant growth and development. Four rates of each herbicide were used, and treatments were replicated four times. Overall, application of trifluralin increased depth to first lateral. However, there were no significant adverse effects on cotton growth and development or nutrient acquisition.