For a pollinizer variety to work, both varieties of pear trees must blossom at the same time or within days of each other. Marine pear trees are good pollinizers for many varieties of pear trees including the Bartlett pear tree.
Plant pear trees 100 feet or less from each other to ensure proper pollination takes place. This distance increases the chance of the pollinator moving from tree to tree to pollinate the blossoms.
Honeybees pollinate pear trees. The small amount of nectar from a pear tree blossom, which has low sugar content, makes it necessary to have many pollinizers (trees) and pollinators (bees) than what other fruit trees such as the apple and plum trees need. One honeybee can pollinate as many as 5,000 flowers a day.