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ANDREW G I R L I N G a n d A L A N W I L K I N S O N

IN January, 1970, "winter b u d s " were being studied by a first year group of boys and girls. For this, winter twigs were obtained from local trees including the Salix babylonica (weeping willow) growing in the school garden. T h e s e willow buds were kept in school for Observation; they were dissected and it was found that many contained catkins. It was noticed after careful Observation with lenses that the catkins bore flowers of both sexes. According to the reference books which were available only male plants are known in Britain but many female flower structures were found in the catkins. T h i s aroused a great interest in the school. T h e findings of these observations were then sent to the firm from which the tree was purchased. They replied stating that they had no knowledge of this condition, and it was decided to consult a higher authority about it. T o this end, a letter was sent to the Royal Horticultural Society at Wisley who replied almost immediately and asked for some samples. It was then obvious that the tree was very unusual in having both male and female flowers on one plant, and so some of the catkins were sent for Observation. Very soon after this a letter was received asking for some cuttings from the tree to be sent to them for propagation. Statistics were then gathered of the distribution of pistillate and staminate flowers on the tree in the school grounds by a fourth year group under the following headings: number of male catkins on a branch, number of female catkins on a branch, number of mixed flower catkins, and the direction in which the branch faced.

Results Total number of branches examined N u m b e r of all male catkins N u m b e r of more male then female catkins N u m b e r of equally male and female catkins N u m b e r of more female than male catkins N u m b e r of all female catkins Total number of catkins examined

171 1,576 462 449 494 907 4,001

T h i s analysis was also to find out whether the aspect of the branches of the tree had any effect on the distribution of male and female flowers on catkins. T h e aspect of the branches and the distribution of male and female flowers bore no relationship to each other.



The actual counting was achieved by markingeachbranchwitha piece of wool (to prevent counting more than once) and examining each catkin on that branch. Just as a matter of interest the pupils were asked to look around their villages and see if they could find any more of these peculiar trees. In fact three more were found within a few miles of the school. Whether they all came from the same source is yet to be found out. Another interesting characteristic of these trees was that none of the seeds produced by the tree appeared fertile. Whether this tree suffered from a genetic mutation some years back is not known and until it is we shall never know how this occurrence took place. It is hoped that this article will interest other groups to look around for other moncecious weeping willows to find how widely they are distributed. Andrew Girling and Alan Wilkinson, pupils of East Bergholt Modern School.

A Monoecious Salix babyonensis at East Bergholt  
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