468 Report of the Department op Horticulture of the 



grains, the possibility of successful pollination is still further 

 lessened. 



Dampness is favorable to the growth of most fungi — which 

 cause our leading leaf and fruit diseases — and such fungi fre- 

 quently attack and ruin flowers during May storms. 



Winds, alone, do comparatively slight, harm to fruits early in 

 the season, but occasionally are strong enough to whip blossoms 

 from the trees and to prevent the flight or active work of insects. 

 If they are drying and long continued they may evaporate the 

 secretion from the stigmas and thereby prevent the retention and 

 germination of the pollen ; while cold, dry winds from the north 

 at. blooming time chill vegetation and retard all plant activities. 

 On the other hand, light breezes on nights when frosts would other- 

 wise occur may sweep away the settling chill and prevent damage; 

 or, in favorable localities beside large bodies of water, may bring- 

 in clouds or fogs to check heat radiation and prevent freezing. 



Unfortunately, at least in a narrow sense, man cannot control 

 the weather to any great extent. Orchard heaters are now used 

 to warm the temperature of an orchard and prevent frosts. By 

 small fires, especially of damp, smouldering, smoke-producing 

 materials, orchards and vineyards may occasionally be protected 

 from light frosts. By proper placing of windbreaks — not so 

 simple a matter as it may at first appear — some advantage may 

 be given tender fruits. By whitewashing the trees in early 

 spring, blossoming may be retarded a few days. A definite 

 amount of heat is necessarv to bring buds to maturity, and since 

 white objects absorb less heat than dark ones, such whitening of 

 the trees may occasionally carry the buds unopened safely through 

 a frost that would destroy the flowers. 



Aside from these comparatively unimportant exceptions, we 

 can do nothing, after the orchard is established, to protect fruit 

 trees from weather stresses. But we can do much to protect 

 future fruit crops by careful study, before we locate the planta- 

 tion, of weather conditions and crop adaptations. It would be 

 most unwise to set apricots, plums and peaches, which are rela- 

 tively tender at blossoming, in any locality where the average date 

 for the last killing frost is as late as May 1" ; vet some late bloom- 

 ing or cold resistant varieties of even these fruits, on some hill- 

 side rightly located or beside a favoring lake, might escape frosts 

 often enough to make their culture highly profitable since they 

 could be sold in near markets never glutted with such fruits be- 

 cause of o-eneral unfavorable conditions. 



