Cotton fruiting forms change in their likelihood of falling off as they age. A study looked at the levels of two plant hormones, ABA and IAA, before and after the flowers bloomed. ABA decreased slightly at blooming and then increased gradually. IAA was high before blooming, dropped at blooming, stayed low for a few days, and then shot up. The high IAA before blooming helps buds stay on the plant, while the low IAA after blooming may cause young fruits to fall off.