Esta pesquisa teve por objetivo avaliar os efeitos das faixas de controle das plantas daninhas e seus reflexos no crescimento de plantas do clone do híbrido Eucalyptus grandis W. Hill ex Maiden x Eucalyptus urophylla S.T. Blake. Os experimentos foram conduzidos nos municípios de Três Lagoas, MS e de Brotas, SP. Os tratamentos experimentais constaram de dois grupos: no primeiro, foram mantidas faixas fixas de controle durante os 12 meses iniciais: 0, 25, 50, 100, 125 e 150 cm de cada lado da linha de plantio do eucalipto; e, no segundo, foram adotadas faixas crescentes de controle: 25 a 150, 25-50-150, 50-125-150, 100-125-150, 100 a 150 e 125 a 150 cm durante os 12 meses iniciais. Aos 49 meses após o plantio foi constatado que as plantas de eucalipto que cresceram nas parcelas com faixas de controle fixas iguais a 100 cm e crescentes superiores a 50 cm nos três primeiros meses mostraram-se superiores em diâmetro medido à altura do peito (DAP), altura, volume e incremento médio anual de madeira (IMA).
Two field trial were conducted in Eucalyptus grandis W. Hill ex Maiden x Eucalyptus urophylla S.T. Blake crops at Três Lagoas, Mato Grosso do Sul State and Brotas, São Paulo State, Brazil, to evaluate the effects of weed control in strip of different width on the Eucalyptus plant growth. The experiments consisted of two groups treatments: group 1 - with constant width control strips being kept during the first 12 months, i.e., at 0, 25, 50, 100, 125 and 150 cm on each side of the Eucalyptus row and, group 2: with increasing width control strips being adopted along the experimental period, i.e., at 25 to 150, 25-50-150, 50 to 150, 50-125-150, 100-125-150, 100 tot 150 and 125 to 150 cm on each side of the Eucalyptus row during the first 12 months. At 49 moths after planting it was verified that the Eucalyptus plants that had grown both in the constant and increasing width control strips, equal to or higher than 100 and 50 cm, respectively, showed higher steam diameter, plant height, volume and annual increment average of wood. These results led to the conclusion that the minimum control strip width should be 100 cm on each side of the Eucalyptus row in order to keep the crop free of weed interference.
