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These plants which grow in this way on other plants, do not, as a rule, greatly injure them, but many have not stopped at this stage. Take, for instance, the Gooseberry growing in the fork of an old tree. Some bird has been eating gooseberries and dropped the seed there. The roots of the gooseberry will grow down into the rotten part of the trunk. Earth and leaf-mould will accumulate there, and it is quite probable that the whole inside of the tree will decay away. The roots of the gooseberry will, if only indirectly, help in this decay.