. Deciduous orchards in California winters. Fruit-culture; Plants. mk .-.~- l. ~^^msm Left: Fig. 9. Winter Banana apple tree on April 1, 1937, showing results of spray of 2 per cent oil containing 3 per cent dinitro-o-cyclohexylphenol, given February 11, 1937, to right side only. Right: Fig. 10. Tilton apricot tree at Davis, March 30, 1930, after exceptionally warm winter. Blos- soms barely open and leaf buds just breaking on long twigs in upper part of tree. Blossoms fallen and leaves nearly full grown on shorter, weaker twigs in lower part of tree. varieties as Rome Beauty receive chilling e
. Deciduous orchards in California winters. Fruit-culture; Plants. mk .-.~- l. ~^^msm Left: Fig. 9. Winter Banana apple tree on April 1, 1937, showing results of spray of 2 per cent oil containing 3 per cent dinitro-o-cyclohexylphenol, given February 11, 1937, to right side only. Right: Fig. 10. Tilton apricot tree at Davis, March 30, 1930, after exceptionally warm winter. Blos- soms barely open and leaf buds just breaking on long twigs in upper part of tree. Blossoms fallen and leaves nearly full grown on shorter, weaker twigs in lower part of tree. varieties as Rome Beauty receive chilling enough to enable them to open and fruit to set well except after unusual winters. Since at such elevations there is likely to be a spring frost hazard, any delay—no matter how slight—in opening of the buds caused by inadequate chilling may be highly beneficial except after a rare winter that is warm enough to cause in- jurious delay, or dying of flower initials in the buds. In South Africa, emphasis is placed on the use of rest-breaking sprays to induce uniform blossoming of the tree so that the calyx spray for codling moth will be more effective. In districts such as Sebas- topol and Watsonville, where apples yield well but where some of the flowers are delayed in opening by rest influence still remaining in spring, possibly such spray- ing might shorten the blooming period after some of the warmest winters and make the calyx spray more effective. We do not have convincing evidence that the benefit would be great enough to repay the cost, even though the DN spray would be given in February only in years when December and January were exception- ally warm and sunny. In southern Cali- fornia, a DN spray may cause more of the buds to open at the beginning of the blossoming season but not nearly all. The blossoming period is long despite the spray. Apricots. Leaf buds of most apricot varieties and fruit buds remaining on the tree do not require as much chilling to enable them t
Size: 1795px × 1393px
Photo credit: © Central Historic Books / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., book, bookcentury1900, booksubjectfruitculture, booksubjectplants
