A basic problem in the decentralized control of a multiple access channel is to resolve the conflicts that arise when several stations transmit simultaneously to the channel. Capetanakis, Hayes, and Tsybakov and Mikhailov found a deterministic {em tree algorithm} that resolves conflicts among

stations from an ensemble of

in time

in the worst case. In this algorithm, at each step, the choice of which stations to enable to transmit depends crucially on feedback information provided by the channel. We show that if

is given {em a priori} then such conflicts can be resolved in time

using an algorithm in which the corresponding choices do not depend on feedback.