This work was carried out in order to evaluate the behavior of spontaneous vegetation regarding the decomposition rates of different soil covers submitted to variable irrigation depths. The vegetable residues utilized were from gliricidia (Gliricidia sepium), pigeon pea (Cajanus cajan), elephant grass (Pennisetum purpureum) and bamboo (Bambusa vulgaris'vitata'). The irrigated depths were characterized as T5, T4, T3, T2 and T1, corresponding to approximately 117, 100, 72, 59 and 38% of the ETo. The decomposition of the vegetable residues was analyzed through covered litter, at 2, 4, 7, 15, 30, 60, 90, 120 and 150 days after installation (DAI) and samples of the spontaneous vegetation were collected at 26, 64, 92, 124 and 152 DAI, in a 0.0625 m² area. It was possible to conclude that the behavior of the spontaneous vegetation is directly related to the kinetics of decomposition of the vegetable residues.
straw; irrigation management; weed management