FERTILISATION OF FRUIT TREES.

Taranaki Daily News, Volume XXXXII, Issue 204, 2 October 1900, Page 4

FERTILISATION OF FRUIT TREES.

Many of the common varieties of pears require cross-pollination, being partially or wholly' inoapable of setting fruit when limited to their own pollen. Soma varieties are L 6apable of selffertilisation, Self - pollination takes place no matter whether foreign pollen is present or not. The failare to fruit with self-pollination is doe to sterility of the- pollen and not to meohanical causes, the impotency being dae to lack of Affinity between the pollen and ovnleß of the same variety. Varieties that are absolutely selfsterile may ba perfectly cross-fertile, The normal typical fruits, and in most ' cftseß the' largest and finest specimens from both the so-called self-sterile and self-fertile varietiesj are crosses. Self-fecundated pears are deficient in seed, and the seeds produced are usually abortive. The cresses are well supplied with sound seeds. Abeut three-fifths of the varieties of pears experimented upon appear to have been wholly self-Bterile, or were greatly benefited by cross-pollination, E«n with those varieties capable of 8< If fecundation the pollen of at other variety is prepotent (more powerful); and unless the entrance of foreign pollen is preuenten, the greater number of fruits will be aflected with it. As rfgarde apples, crossing give decidedly better results in all cases than self-pollination. Ih? Baldwin, which wes experimented upon freely, may be cited as a variety that comes as near being s« If fertile as any, and yet even this is far fr< m being entirely eo; for in the best trees the percentage of fruit resulting frcm Belf-po'.lir ation was not more than a fourth of that which resulted from crossing. Seme of the Baldwin trees in faot seemed to be self-sterile, and all the varities occasionally set self-pollinated fruit. Too much confidence should hot be placed in a strict classification even of pears, as a variety may be quite selfsterile in one district and yet be quite self sterile in another, or in Bome other season. A mong the sorts of pears found more or hS3 completaly celf-sterile are the Bart'elt, Anjou. Boussock, Clairgeau, Gapp's F. vorite, Sheldon, Louiia Boone de Jersey, and otber common varieties. Still lees would it be possible to classify apples. A variety may bo le'f-fertile one year and quite the reverse another, The weather at blooming time is important. At this period it exerts both a direct and indirect influence on the setting of fruit, Even when not injured by froets the 1 blossoms are often chilled by the cold to such an extent as to interfere wiih fecundation. Moderate cold renders the self-fertile trees self sterile, and severe oold renders from sterile to I cnrs-pollinition as well. Warm and , sunny weather at this time indireotly aids the ferti'iz vtion by favoring insects in. their work of crose-pollination. , The results of set-pollination in apples are very interesting. Apples resulting from Eotne experiments were collected and Btu 'ied and the results were found to be parallel with those obtained in the experiments with pears, the crosfi s being larger, more highly oloured, i nd better supplied with seed. Fcr ix&mple the hand crossed Baldwin apples were highly coloured, well matured, and dontaiced abrnfantseeds, while the sdf-feitilizd were oily slight'y colored, were but one forth to f two-thirds the regular e r z3 and seedless. The crosses wer9 in other words like the better specimens ef apples not bagged from the same tree, and the self-fertilized fruits correspond with the undersized, poorly colored specin ens frcm the same trees. The number of inßect visitors in any ordhard determines to a great extent the amount of cross pollination carried 1 on. The pollen of the pear and apple is not prodnced in sufficient quantity ' nor is it of the right censistency to be carried by the wind; and the pollinal tion ef these is therefore dependent on the activit yof insects. If there is no apiary in the neighborhood, therefore each large orchardist should keep a number of hives of bees. Honey bees and other members of the bee family are the best workers in cross pollina tion.—Exchange.