Activities of Insect Pollinators and Orchard Planning

A large number of insect species belonging to insect orders Hymenoptera, Diptera, Coleoptera, Lepidoptera, Thysanoptera, Hemiptera, Hpmoptera, Orhtoptera, Derma-ptera and Neuroptera visit blossoms and effect pollination of a large number of fruit, vegetable, oilseed and fodder crops. The relative importance of the insects as pollinators is discussed and it is concluded that flower flies, solitary and social bees are the more important pollinatois among these. The habits and behaviour of the various insects while visiting the blossoms are outlined and the problems facing the orchardist for making airangements for sufficient insect pollinators in an orchard at "fruit bloom" are pointed out.

As many varieties of apples, pears, plums, peaches and cherries are self-unfruitful, it is necessary to provide cross-fruitful varieties in their plantings. The numbers and most suitable location of such cross-fruitful variety trees in some planting plans is examined and it is suggested that a row of the crossf-ruitful variety trees should intervene after every row of the main variety tree or a branch of each main variety tree should be grafted with the cross-fruitful variety. Such arrangements are necessary because of the localisation of flower flies, bumble bees and honey bees to small-areas during their visits to blossoms.