Is it possible that a doomed eucalyptus tree will become a decisive factor in the Burlingame City Council election? It’s not out of the question. All three challengers for two seats on that august body _ Peter Comaroto, Gene Condon and Jerry Deal _ have indicated that the current council’s inability to reach a timely decision on the tree’s fate indicates, in their view, an inability to handle the responsibilities of public office expeditiously. Two incumbents, Terry Nagel and Russ Cohen, are seeking re-election Nov. 6. Nagel, as mayor, has been a key figure in stretching out the process that decided the Easton Drive euc’s fate. In the end, it took more than three years to come to a conclusion on the matter. After a great deal of agonizing and what seemed like interminable studies, analyses and delays, she wound up casting the decisive vote to bring in the chainsaws. Cohen has opposed the tree’s removal. But he has not been in the forefront of hastening the process. Far from it. The challengers have expressed the opinion that the council’s behavior is symptomatic of an emphasis on micro-management and the trivial. They may be correct. But it remains to be seen whether all of this will swing the election in the direction of the challengers. The three of them are running against two entrenched incumbents and it is likely that Comaroto, Condon and Deal will wind up fighting each other for the same crucial votes from those unhappy with the performances of Cohen and Nagel.