HISTORY IN PEAT.

Auckland Star, Volume LXVII, Issue 115, 16 May 1936, Page 10

HISTORY IN PEAT.

THE WORLD'S CLIMATE MISS CRANWELL'S STUDY. J FASCINATING RESEARCH. A fascinating field of research has been opened to Miss Lucy M. .Cranwell, botanist at the Auckland War Memorial Museum, as the result of a visit overseas extending over a year. Working in company with distinguished European botanists, Miss Cranwell will study the peat deposits of Xew Zealand, and, from their contents, she hopes to be able to throw some interesting light on the history of Xew Zealand—extracting at the same time information which may be of importance, economical!}*, to Xew Zealand. Miss Cranwell returned this week, from a trip which was intended originally merely for the purpose of attending the Imperial Botanical Conference in London, and the International Botanical Congress in Amsterdam —but which became an intensive period of study, and research. In England she tramped and climbed, studied the field of botany there, and met many interesting scientific personalities. She also went to Sweden at the pressing invitation of botanists there who are keenly interested in the botany of Xew- Zealand. It was there, under the tutelage of Professor Lennart von Post, and Professor du Keitz, that she was introduced to the new field of investigation.

Forest Changes. Miss Cranwell has always been interested in the study of peats, and she discovered there that a technique had been developed whereby from the fosselised tree pollen held in the various strata of peat, the changes in forcstation, and the weather conditions indicated, since the glaeiation of the world could be tabulated. Considerable progress had already been made in the 'jseience from the study of European ypeats, but a research worker was { required to tap the knowledge held in I the peat bogs of the southern half of ■the world. : A fine collection of New Zealand peats ■ lad been made by Professor Carl when on a visit to New '-. Zealand some years ago, but their ;. resources had not been tapped because f-of a lack of complete knowledge of the ■i.New Zealand varieties of trees. Miss 1 Cranwell's assistance was sought, and Rafter a period of study and research at ■ ifche University of Stockholm, during I which she made many botanical expediI tions in the boglands of Sweden, she the professor produced a preliminary Ijjbaper on the subject. It has not yet ijjlien published but Miss Cranwell states the results obtained from the work are interesting in that were not quite what was expected. Since the Ice Age. ; ' -Now Miss Cranwell has returned-and Kher real work is to begin. The general trend of world weather from the Ice Age, as : it is generally called, has been towards a peak of heat. That period, itMs believed, has passed and the world is again cooling off. With each successive period different types of tree -were dominant, and it is from this/fact that yihe source of knowledge has conje. Blown viii&m th'e tree in each' successive period : pollen lodged in the peat where it held, and so the weather .history il&d the tree- history of the world';: in ..-,th# various ages was kept for the botanist. liSThe. technique of the research work tan arduous process involving', the ection. of the various strata of peat, i their examination under the rnicroThe various pollens have to be identified, an 4 counted so that' the .(dominance of trees in the various period be determined. Geological research ■>sßttd the finding of relics of past .ages the strata and so the information >0* compiled. In Europe the study is easier by the knowledge already •Jield of successive stages of civilisation ypind the Ice Age has been fixed .with •yig3egree of accuracy at about 8000 years i|j|jjb. Lack of knowledgeof New Zealand's |pi|ly history makes the work much jttfcSre difficult here, but it is hoped J as a of the research ■to make some discoveries in this direction. Interesting 'Discoveries. The , tendencies of,- climatic changes, the uncovering of early history in many fields, and the possibilities that, discoveries will be made of assistance in forestry work, opens an interesting field of,study, and Miss Cranwell is looking forward eagerly to her study of New Zealand peats. Ak she points out, there 4s an element of thrill even in ,, the knowpledge that relies of the Ice Age He but 'ji :R few feet below the surface of our

world. ■ For instance, it has discovered that in parts of Sweden, f ildw subject to a severe climate, grapes «rice grew in the open. Then, too, the 'Study of tree pollen has added to medical '■Knowledge in the treatment of hay '•fe'yer. •K! From her early investigations Miss eays that the indications are •towards colder and drier climates, the dominance of trees indicating that the 'Kauri, oake, alders, limes, and other 'trees of warm climes, are becoming more 'aid more dominated by spruces and "Tnrch. Mostly it is a gradual change, Tjiit research has shown that there have Tjfeen very sudden changes. "./Miss Cranwell is also interested in seaweeds, and while in Europe she was able to obtain duplicates of a valuable / collection made in New Zealand in 1874, and named by the authority, J. C. Agardh. This collection will be of great interest to New Zealand botaniste. Referring to university life in Sweden, Mis.s Cranwell paid a tribute to the interest of the Swedish Eoyal Family in scientific work and the good it had dofie there. Professors and students met on a much more equal footing in the Swedish universities than in the British ones, and their expeditions together and the community life of the institutions was refreshingly valuable to the student. I