Because there are few trees in temperate forests, it is safer to transport pollen by insects or birds. | Wind pollination is a safe reproductive strategy for trees in temperate forests where there are only a few dominant species and, therefore, many individuals of the same species. | Wind pollination requires production of large amount of pollen, which must be released at the right time and under the right conditions to extend its range. | Most wind-pollinated trees are deciduous because evergreen needles compete with the stigma for pollen, making wind pollination uncertain. | Wind-pollinated plants usually have small petalless flowers which often grow in catkins that produce a very fine-grained pollen. | Wind-pollinated trees must grow in regions that are only moderately windy because strong winds will blow the tiny pollen grains past the stigma. |
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