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Northern red oak (Q. rubra L.) seeds were dormant and required 10 weeks of moist, cold stratification before a large percentage of the seeds would germinate. White oak (Q. alba L.) seeds were not dormant and germinated immediately upon falling from the mother tree. A transfer of mass from the cotyledons to the embryos occurred during germination of red and white oak seeds. No detectable transfer of mass occurred during stratification of the red oak seeds. The longer the red oak seeds were kept under stratification conditions, the shorter the period of time required for seeds at 26°C to begin germination. A significant decrease in GA-like activity occurred during the first 5 weeks of stratification of red oak seeds. No transfer of activity from one pH-dependent ethyl acetate-soluble fraction to another occurred. A slight increase in GA-like activity occurred between 5 'and 7-1/2 weeks of stratification. Red oak seeds stratified for 18 weeks contained significantly more GA-like activity than those receiving lesser periods of stratification. When l8-week stratified red oak seeds were warmed to 26°C, germination commenced within 2 days and the levels of GA-like activity decreased. White oak seeds contained substantially less GA-like activity than red oak seeds and amounts of activity in white oak seeds changed little during cold storage of the seeds. Radicle extension growth of white oak seeds began even at 5°C and complete seed germination began within 2 days of warming to 26°C, independent of the time in cold storage. Cytokinin activity was measured in the ethyl acetate and n-butanol fractions of red oak seeds. Concentrations did not change between 0 and 5 weeks of stratification. / Ph. D.

Newspaper article: "A good tree is worth saving”

Newspaper article: "Planted 100 years ago”. At the bottom of the article, a typed addition reads: "In January 1960 the old tree which stood just inside the gates of the Botanical Garden's Grey Street entrance was partially blown down in a gale, and ordered to be removed in toto. It had been planted by Col. Grahams, the founder of Grahamstown."

Newspaper article: "Century of growth”. Article reads: "Lovely 20-year old Denise Baker reads a plaque on an almost forgotten oak in St. George's Park. The tree was planted 100 years ago today. The inscription reads, "This tree was planted by Nathaniel Adler, Esq. on the occasion of the visit of H.R.H. Prince Alfred, August 6, 1860."

Newspaper article: "Ancient oak owes longevity to plaque it stoutly bears”. Plaque reads: "This tree was planted by Nathaniel Adler, Esq. on the occasion of the visit of His Royal Highness Prince Alfred, August 6th 1860".

Newspaper article: "Sit under oak and think of our ancestors”.

Typed note: "Oak Tree. As at 1977.11.19. In the northwestern part of St. George's Park, Port Elizabeth against the fence of the granstand at the Union Cricket Ground is an oak tree bearing a plate: 'This tree was planted by Nathaniel Adler, Esq. on the occasion of the visit of H.R.H. Prince Alfred, August 6th 1860'. This tree has therefore been there fro 117 years, but it is a very poor specimen of oak with a weak spread of branches, certainly not a good example for its age. It is typical oak".