Trees give your certain gags bonuses. So if I were to plant a throw tree, my Birthday Cake would do 110 instead of only 100. So if you have maxed a track, then I would go with that, as it is a good boost. If you have all your gags maxed, pick your favorite. By the way, if you have a level 7 gag, you can pick your tree once a day. (That means one level 7 gag at least a day!
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