Influence of Date of Flushing on Flowering in Pinus banksiana
NUMEROUS attempts have been made to relate the year-to-year variability in flowering of forest trees to seasonal fluctuations in weather conditions which, in turn, are believed to influence the internal physiological processes regulating flower initiation1. The pronounced effect of photoperiod on flowering, noted in many herbaceous species, appears to be lacking in forest trees, and observations indicate that most trees are photoperiodically day-neutral2,3. However, until more definitive experiments have been undertaken, photoperiod cannot be ruled out as a factor influencing flower formation.
REPRODUCTIVE DEVELOPMENT IN LOBLOLLY PINE. II. THE EFFECT OF AGE, GIBBERELLIN PLUS WATER STRESS AND OUT‐OF‐PHASE DORMANCY ON LONG SHOOT GROWTH BEHAVIOR
The effects of age from seed, out-of-phase dormancy, and gibberellin treatment with water stress on the reproductive and vegetative development of the long shoot terminal bud were observed. Scions of different ages were grafted onto 1-yr-old rootstocks, and the younger scions grew more and produced fewer strobili than older ones. Out-of-phase dormancy promoted both male and female flowering at all ages, but the older scions responded better. Gibberellin4,7 plus water stress promoted development of female strobili only. Treatments that promote flowering also increase the size of the resting bud. It is proposed that treatment effects promoting flowering appear to fall into two categories: 1) Those which promote the formation of a resting bud, and 2) those which affect the subsequent development of resting buds which have the potential to
BOTANICAL DERIVATIVES CONTRIBUTING TO THE STRUCTURE OF MAJOR PEAT TYPES
Samples of peat from the Fort Churchill area in Manitoba have been investigatedin the hope that a quantitative system would be found to explain peatstructure. 'This entailed the developnlent of a method which would allow detailedstudy of the peat with the organic elements in their in situ position. Thequantitative results, categorized according to botanical relationships, were usedto indicate the structural differences in the samples studied, and also to elucidatethe vegetational succession of the samples. Relationships between subsurfacedetails and surface vegetation are discussed.