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When the local scrub jays and pinion jays find the seeds from a pinion pine, they often hide them for later. The birds have excellent memories for finding the seeds, but sometimes the seed will fall far enough down into a crack in the rocks that the birds cannot get to it. In the spring, the seed sprouts and begins to grow. The crack in the rock traps rain water and bits of debris that provide the growing tree with water and nutrients. The tree will not grow very large, but can live for a very long time, becoming a natural bonsai.