NEWSLETTERS OF THE TREE SOCIETY OF RHODESIA FOR 1969
The following is a summary of the news, events and happenings of the Tree Society of Rhodesia from the records we have available for 1969
Tree Society of Rhodesia Newsletter March 1969 (no letters for January or February)
Dear Member,
16th March. Audley End, Darwendale. 1000 hours.
Outings have been arranged for the third Sunday in the month except for October and December when there will be an evening show on the third Monday of the month.
The Minutes of the Annual General Meeting will have to be held over until next month. The account of our visit to the Arcturus Swamp forest will appear in the April Science News. The current issue contains a shortened version of my paper on the Makabusi and I trust this will encourage even more support. Several pledges of active support were received last week, and I was also interviewed by Press and Radio. In every case I was asked a number of questions as to why the veld is in poor state. It seems that the degradation of the veld is attracting some interest and it is therefore the subject of this Newsletter. Moreover it will supply me with the answers to the questions in a handy form. Our interest may lie primarily in preventing the loss of relic forests and uncommon species, but as we have seen on outings the loss is due to general denudation and soil erosion, which also threatens the economic well being of the country.
THE ONSET OF THE DEGRADATION OF THE VELD
There is scarcely need to say that those who have had the opportunity to observe and study the veld are seriously worried. Most of our ranches are in a poor state, most of the grazing in the Tribal Trust Lands is in a bad state and on farms, National Parks and other land the veld is in various stages of decline. The effect on the national economy and water supplies, is already serious and could become grave.
The degradation has occurred unnoticed except by a few because it is a slow insidious process even less apparent than the first stages of soil erosion. When changes are noticed they are blamed on the vagaries of seasonal rainfall but our rainfall has always been erratic.
The first mistake made was the “taming” of natural pasture by heavy grazing and fire. Both may be necessary and if used with discrimination can do good but misapplied or overused they eventually cause great harm. Real or apparent benefits from over grazing and fire were immediate but the signs of damage did not attract attention when they first appeared.
Official advise then went to the other extreme, no burning of the veld and light grazing. Adoption of this advice did not prove successful for various reasons. With light grazing the stock eats down repeatedly and thus reduced the better kinds of grass giving the poorer grasses and scrub the opportunity to increase. An important factor in the evolution of our veld was the infrequent fire which raged through a mass of dry fuel and had sufficient heat to destroy the scrub, therefore an occasional hot fire was necessary. Lastly a process of change once commenced is apt to continue..
The stock man was in a quandary. Whatever he did caused deterioration of the veld. Scrub and worthless grasses increased and the better grasses became less. He was then advised to destroy the scrub, reduce the number of trees, to fence off the grazing paddocks and to take the mower round the veld. This was at a time when prices for agricultural products were sub economic not all properties were fenced round the boundaries and mowers were uncommon. Then followed the last war when, for some years afterwards, fencing wire and implements were in extremely short supply.
The only solution appears to be the “high density short period system” of grazing management, that is each paddock is grazed for a fortnight or less and the rested for 6 months. A paddock to be burnt is out of use for 18 months, and there should also be a few paddocks in reserve in case of drought. Water must be supplied to each paddock, usually necessitating miles of piping. The capital required is large and the return no more than could be expected by other forms of investment. Because of the cost and uncertainty of the results the system has only recently received qualified and hesitant approval. The uncertainty is due to the failure, until quite recently, to commence controlled experiments, and one cannot expect conclusive results of the effect on the veld of any grazing experiment for many years.
The Tribal Trust Lands
In the communal areas the position is far worse. Everywhere except in places difficult of access or where tsetse fly is present the land has been seriously over grazed for a great many years. Over a large area the soil has been so damaged that full recovery is impossible and damaged to the extent that grass of any use as grazing can never be restored.
There is a natural reluctance to deprive the African of his stock. It is difficult to explain to Africans and officials with no basic knowledge of pedology and ecology that the soils and grazing are on the down grade, irreversibly so unless most stringent measures are taken, when the cattle are still in good condition and field staff and funds are hopelessly inadequate, and the terrain, water supplies or siting of villages and arable lands impose difficulties to the introduction of grazing management.
Attempts to overcome some of the difficulties were made first by the introduction of Centralization, an expedient which involved the consolidation of arable plots and the re-siting of villages. This was followed by the Land Husbandry Act of which the object was soil conservation, better farming and grazing management. It achieved temporary success in places where staff was adequate but these reverted when staff was moved to new areas. In turn both measures were withdrawn. Great faith is placed in Community Development but this has not yet brought any marked improvement to the soil or the grazing. Greater success might have been achieved to date if more emphasis had been placed on raising the standard of living of the people by improving their incomes increased production or alternative sources of income such as home industries. Remarkable results in the improvement of crop yield have been achieved in the very limited areas where it has been possible to provide adequate advice and assistance.
A two camp system, whereby half the grazing was rested during the growing season, was introduced with some success in a few Tribal Trust lands but it appears was ignored in many cases after the staff were moved. It is now hoped to start demonstrations of grazing management and that the subject will be included in the conservation training courses for Chiefs and Headman.
After 40 years of agricultural demonstration most African cultivators have scarcely changed their methods.
After 30 years of attempts to control erosion in arable lands it is now hoped by a supreme effort to complete the task in three years. Grazing management has always been equally essential but except for limited periods in limited areas it has been neglected. With few exceptions all grazing was in a poor to bad state, and small areas had gone beyond the stage where recovery is possible when I inspected, the majority of Tribal Trust Lands in the nineteen fifties. The few I have seen since show no improvement.
Farms and National Parks
These are dealt with together solely because it is still possible to affect a good recovery in both classes of land as with few exceptions permanent damage has not been done to the soil. In the Parks interrelated changes are taking place in the composition of the Flora and Fauna due mainly to development of facilities for tourists, and measures to minimize the changes must be taken. On the farms it is much less difficult and costly to introduce grazing management. It was seen, however, on our last outing that mere rest and light use of grazing does not halt an already commenced process of degradation. Positive measures are required.
The process of degradation of the veld
The association of plants present on any site is in a state of balance with the conditions which prevail there. Any changes in the conditions leads to a chain reaction, for example the creation or elimination of a drinking place for game results in changes in the species and numbers of wild animals present and this will lead to changes in the amounts of different plants present which in turn leads to changes in the kinds of birds and insects and so perhaps to further changes.
Our veld was conditioned by and to fire. Before Man knew how to make fire occasional fires were caused by lightning. When Man later used fire to drive game and to attract game to places where the animals could be more easily hunted, the population was small and nomadic so the fires were probably infrequent.
The cultivation of crops reached the southern two thirds of Africa much later than the rest of the world. The population remained small until the advent of the European and shifting cultivation was satisfactory as fertility was restored by reversion to woodland or forest. The numbers of cattle were small and the numbers of game were large with the result that the entire variety of grasses, herbs and bushes was grazed or browsed. The fires would not occur annually over the whole countryside and because of the light use of the veld they were hot enough to reduce the trees and bush and thus increase the area of grass.
Over the period of hundreds of years of iron age man, planting and annual community suited to the conditions became established, but the conditions were artificial and therefore the balance was delicate. Any change in the conditions would produce changes out of all proportion to the previous ones in the vegetation, animals and soil. This was realized only after much damage had occurred. We also overlooked that 2 000 years ago most of Europe consisted of forests and infertile soils and by a very long hard effort had been converted into fertile farm land, under climatic conditions very different from ours.
In Rhodesia we learnt by bitter experience and though today the standard of European farming is high progress on veld management has been slow, in fact experiments on the high density short duration method were commenced only recently.
From almost the beginning the criterion of the results of grazing management was the number of pounds of meat that could be produced per acre, even the official experiments on grazing management were directed to that end. To the African numbers not weight is still the criterion.
At first annual fires and heavy grazing did little readily apparent harm, and though it may be desirable to reduce rank growth, the grass is being weakened and the better species may be dying out when a pasture is given a good return measured in pounds of meat.
Perennial grass is also to sprout leaves soon after rain has fallen because of the plant food stored in the roots. If the young leaves are not permitted, eventually to mature the reserve of food is not restored to the roots and the grass plant is steadily weakened and may die. Grass, particularly annuals, must be permitted to seed, and conditions must be favourable for the germination of that seed, i.e. presence of moisture and a protective cover. The grasses which contain the most nutrients in their leaves are not only selected by the cattle, but also put the biggest demands on their roots and therefore are the most easily damaged. They are replaced by the grasses with less leaf and less food in the leaf.
When this stage is reached there is an inducement to burn to force the now poorer grasses to produce new leaves. These grasses sooner or later are no longer able to produce sufficient material for a burn. This stage was reached in much of the Tribal Trust Lands about 20 years ago. The stock then by repeated clipping forced the production of a succession of new shoots. Even at this stage the hardy indigenous cattle may be healthy. This misleading condition of the veld and cattle is general, and some Trust Lands have already reached the next stage, the almost complete disappearance of all but the smallest of the poorer grasses.
Generally the majority of the ranches have reached a stage where the better grasses have been much reduced and there has been a big increase in scrub bush. There are areas though where the grass has all but disappeared.
Even more important than the damage to the grass, which it is possible to remedy at a cost, is the permanent damage done to the soil. The Rhodesian climate and topography are not favourable to the production of deep rich soil, and what we have is more easily damaged or eroded away than in most countries. Under natural conditions the soil is covered by a litter of dead plant material which protects it from the heat of the sun which would otherwise destroy the humus near the surface, and also from the battering effect of the raindrops. If litter is absent the surface of the soil becomes less impervious, also the raindrops stirrup mud which is carried away by the increased run off, sheet erosion commences.
The shallow roots of grass and plants give the soil the ability to spring back after being trodden on. Their decayed roots provide channels for the ingress of air and water, both equally necessary for growth. The soil is full of microorganism which has many important functions to perform.
The humus and the clay are almost the sole source of available plant food, but are extremely important as together they form elastic cement which binds loosely together the smaller grains of sand into crumbs. These crumbs absorb and retain water for later use by plants, and also hold the soil as an open and loose mass, but resistant to erosion. If the humus is destroyed the clay is freed and can erode away or leached down below the depths of shallow roots. The soil then becomes compacted and hard, less able to retain water, and air is unable to circulate in it. It ceases to be live and becomes a sterile mass with none of the virtues of soil..
The lack of oxygen and water in the soil does further harm to the shallow rooted plants and grasses. Less water is able to penetrate the soil and the amount that runs off will be increased, and as there is by now no litter and only a sparse cover to restrict the flow of water the speed of runoff will be increased. This will cause sheet erosion, and in the depressions and valleys flash floods which will cause gully erosion.
The supplies of water deeper in the ground are reduced, and the first effect of this is the failure of perennial streams, but wells and boreholes may go dry, and dead branches will appear on bushes or trees, and in places trees may even be killed.
On our last outing we could see that this process was continuing on veld which was not greatly damaged in the past, and has only been lightly used for many years. The woodlands on the upper slopes lacked topsoil and litter, on the lower slopes the soil was hard and impervious and the grass cover was changing to poorer species, at the bottom a swamp forest was becoming dry and its less common trees were suffering gully erosion was still active. This was on an area with good rainfall and inherently fertile soils. From this one can imagine what has happened where soils are less fertile, rainfall erratic and misuse has occurred over a far longer period. Recently in the Low Veld baobabs died by the hundreds in places that do not appear to have been badly misused at any time. These ancient trees must have survived previous drought cycles. The only answer is that during heavy rain less water penetrates the soil.
Yours sincerely,
Douglas Aylen, President
Tree Society of Rhodesia Newsletter April 1969
Dear Member,
Slide Lecture on “Improving Trees” at the AGM. It is understood that the issue of Rhodesia Science News for May will feature afforestation and will include an articles on the subject of Mr. Barret’s most interesting and enjoyable lectures.
Degradation of the Veld. It is believed that some members do not appreciate the reason for the Society’s interest in this matter. I have written comments for the general readers of Science News and hesitate to repeat in the Newsletters, for a more specialized reader, what is written elsewhere, I gave a brief explanation at the Annual General Meeting, the minutes of which will be posted. Those who came on outings during the last few months will also have heard discussions.
I trust readers of this Newsletter will see my difficulties but will anyone who has missed some of the points please write to me and I will deal with any matters that I have overlooked in the next one.
One comment that was passed on to me is that I gave no answers to the problem. The last Newsletter gave my views on the history and causes of the degradation of the veld. It is for Research to give the answers. I did suggest that a possible solution is the “high density short duration” system of grazing, and in my next notes in Science News I have suggested the multipurpose use of fodder trees. However, any research on either subject is so recent that firm results cannot be expected for years.
We were in the same position as regards soil conservation in 1937 but so many farmers had tried out variations of the limited official recommendations that the answer was there for the seeking. We are not in such a happy position as regards veld management. More advice has been put out for a longer time but it has had far less effect. It has always been known that grass should be permitted to produce enough mature leaves to replenish the roots between periods of being eaten down, and that daily trekking of cattle from kraal to pasture, to water, and back to kraal is a bad practice worsened by herding while grazing.
Already parts of our veld are becoming desert and to continue ignoring these simple principles will result in up to half our veld becoming desert. We will lose not only grass, but trees, soil and water in those areas. Irrigation of a small percentage of the land within those areas is no answer, in fact flash floods and silt will destroy the storage works.
The answer is to adopt now what we know and not wait for the impossible miracle.
The Sunday Mail of 23rd April carried items on the Makabusi Scheme and the Hunyani Settlement near St. Mary’s Mission, with a photograph of the latter. What it did not report was that a few years ago the area of the settlement was comparable to the woodland we are seeking to preserve. I recommend readers to look at the Settlement; it can be seen from the bridge just below Prince Edward dam.
A number of members who have not seen the woodland and the upper half of the Makabusi River have asked for another outing there. It is planned to make a joint visit with the Natural Resources Society on Sunday 25th May, I would like to know numbers who would come to an extra outing, so please let me know.
Commission of Inquiry into National Parks: The decision to appoint a Commission is welcome news. I am sure all will regret that Fraser Darling is unable to serve on it. I have a copy of a recent paper by him with the rather imposing title of “Man’s Impact on the Biosphere” but I can assure you it is as readable as any of his popular books on nature subjects, some of which at least are known to most people.
The paper is well illustrated but I believe all the pictures could be replaced by photographs taken in Rhodesia. I would then like it to be printed and made available to all schools as well as adults interested in their country or the countryside.
Outing to Audley End: A brief report of the day will appear in the April Notes. An account of the naturally growing and planned indigenous trees was in the April – June 1967 issue of “Trees of South Africa”. No item that could be put in a Newsletter would do justice to Audley End so instead, we will circulate copies of the journal to members on request.
Yours sincerely,
Douglas Aylen, President
Tree Society of Rhodesia Newsletter May 1969
Dear Member,
April outing, Botanic Garden. Some forty members and guests were taken on a most interesting tour by the Curator, Tom Muller. Most of us had read descriptions of the Garden and the Herbarium, the objects and work being done there. The tour gave us a good idea of the layout into ecological zones, families and other regions of Africa, and the future development. Enough work has been done to enable us to appreciate the excellence of the plan and that there is every chance of it becoming a place of great interest and beauty provided funds and facilities on an adequate scale are forthcoming.
Future Outings: During the last twelve months attendances have been good at places both near and distant, and they are increasing. Our activities are, therefore, being increased to more than twelve a year.
May outing to Poti Valley, 18th May – all day: The venue of this outing has been changed by a few miles as on the “Fern Spruit” on Ceres Farm there is a wonderful riverine forest in which we recently discovered not only the trees which are the main object of our visit, but also others not so far recorded in Mashonaland. On the return journey we will stop about 200 yards past Woodlands homestead to a large Zanha golungensis, also present in the forest, and a new discovery, and again about 2 miles further on at a bend near the top of the hill where there are trees we have not seen on our recent outings. Bring tea, lunch and cold drinks.
Makabusi Woodland, 26th May (Whit-Monday). This is an extra activity, as a result of requests, to which other societies have been invited. Although many of us have seen the area I hope the tree Society will be there in force. There will be the opportunity to discuss the scheme with others and also to ask questions of experts. After the proceedings have finished, which should be by 11.30 it is hoped that members will wander round with the many guests they have brought and perhaps have a drink or a picnic lunch. Please come in force and let the public know that we mean business. A lot of work has been put into this effort. The City Council has had to take notice. It remains to make a convincing demonstration.
Without doubt we will receive requests to take more parties round the Makabusi, and if any members who miss the Whit-Monday Outing would like to join a party later will they please write to me giving phone number as notice may be short. The City Council and Departments are taking a big interest in the woodland and will want to go over the ground. There could by any of four decisions the Council could make. A) cut up all but the riverbanks into plots b) cut up most of it and make the rest into formal parks c) reserve the land and do nothing and d) adopt our recommendations. Please take as many friends as you can to see the woodland.
Do not forget to hammer home that the Makabusi Woodland must be a natural park. It must have an educational purpose, it is essential to interest children in natural science as this leads to an interest in other sciences, which is becoming increasingly important. Then, too, the public must be able to appreciate what is happening to our veld, which it certainly appears very few are able to do. Also there must be facilities for quiet relaxation for the less active.
This week’s issue of the Sunday Mail had an article on the Tribal rust Lands which we through our knowledge of what can happen on some European land can appreciate fully, but I wonder how many purely town dwellers get a true understanding of the story. One of the points was trees, or the lack of them. Farmers who live next to a TTL without trees are raided for poles and fuel. After being approached by some of them I enquired of the Lands Inspectorate as to the position and was informed that trees are not a natural resource and that they are not interested unless the destruction of trees was causing erosion. I wish to say that to the African trees are essential for fuel roof poles, cattle kraals, garden fences etc. Also that bad methods of cutting trees have converted much open woodland into dense grassless and worthless scrub, and this leads to overgrazing and thus erosion of the rest of the area.
Add to this the view expressed by a man with some influence that clearance of trees in the Makabusi Woodland can be made good by planting more street trees, also that an association formed to arrange public lectures and debates was not aware of the Makabusi, the Scientific Societies and much of the various objects and aims and you can realize that we all have a long row to hoe.
Yours sincerely,
Douglas Aylen, President
Tree Society of Rhodesia Newsletter June 1969
Dear Member,
Outing to Hunyani Falls, all day. 10.30 am.
Outing to Cleveland Dam Reservation. Morning only, but picnic lunch if you wish. Main object to give members a chance to ask questions but there will be trees and some game to see.
TREE SOCIETY OUTING TO CERES FARM, notes by Trevor Gordon
The outing to Mr. Morkel’s farm Ceres was very well attended and proved to be of great interest to us all. Approximately 30 people attended and was most heartening to see some new faces. A vote of regret at the absence of our President was expressed and also a wish that he make a speedy recovery.
The farm is situated about 46 miles from Salisbury on the main Shamva road. Although we took a dirt road from the 30 mile peg it can be approached from the main tar at approximately the 46 mile peg which leaves only .5 mile of dirt road. The area is an extremely rich pocket of soil with a lovely stream flowing through it. Because of these ideal conditions the growth of everything is luxuriant. Being very sheltered it is not prone to severe frosts as no evidence of last year’s winter could be seen. Some extremely interesting trees and shrub species were in evidence and it was quite a change to find the unusual rather than the commonplace. We were fortunate to find some Cordia abyssinica still in flower and very heartening to find this area richly endowed with them Some of the other striking trees seen were Zanha golungensis, Albizia versicolor, Rauvolfia caffra, Ficus sycamores, Oncoba spinosa and the sausage tree, Kigelia pinata. Several beautiful specimens of Acacia species, Diospyros mespiliformis and a large Ekebergia capensis were also seen.
The creeper Pterolobium stellatum added colour to the area as it was found creeping right to the top of some acacias making a lovely show with its yellow flowers and bright red fruits One aspect of the area that was very encouraging was the presence of large numbers of seedlings of most of the uncommon varieties ensuring their survival. However there was another aspect which, if not checked, could be detrimental to this beautiful spot. A fairly large avenue of Toona ciliata has been planted close by and young seedlings and saplings of all sizes could be seen over most of the area. There is no doubt that this prolific tree is making inroads and in time will oust the others. It was unfortunate that we did not get time to label some of the more striking trees and prepare a list for Mr Morkel. However, this pleasant task can be undertaken sometime in the near future. We had lunch in the most pleasant setting under the dense canopy of the trees and creepers and beside the gurgling stream. After lunch a general discussion took place on the ways and means of identifying trees and shrubs from their leaf structure flowers and fruit. The reasons for these isolated pockets of forests all over the country was also given some thought.
It was encouraging to see the Society’s field card being used freely, let us hope that this will continue and be a means of really improving our knowledge of our Flora. We all dispersed at 4.00 after a really wonderful day.
NOTES ON MURAHWA’S HILL by Trevor Gordon
Murahwa’s Hill is situated on the main road to Umtali approximately half way between Christmas Pass and the Town. It has been declared a protected Nature Reserve and is being looked after by Mr. N. Chase, one of our Naturalists and dedicated men to our Flora. Mr. Chase has cut paths through this area so that the whole reserve can be examined in comfort. I say this because the area though rich in trees and shrubs is also blessed with two of the most soul destroying creepers to be encountered in the veld, namely Acacia schweinfurthii and Pterolobium stellatum. Archaeologically it is extremely interesting as from excavations and findings of numerous artifacts, it is evident that the area supported a large population. There are numerous rock paintings but unfortunately the area has been visited by vandals and some of these paintings have been scraped off the rocks. There is a rock that was used as a mortar for crushing gold bearing ore, a rock gong and various caves. The views one gets from various points along the paths of Umtali and its surrounding countryside are superb.
There are some 132 trees and shrubs which Mr. Chase has identified so far and he feels sure there are some more to be found. Some very beautiful specimens of trees not very common can be seen such as Cordia abyssinica, Craibia brevicaudata, Euphorbia ingens up to 35 feet tall with boles 2’6” diameter. Ficus subcalcarata, Heteropyxis natalensis, Homalium dentatum Muriea discolor, Terminalia gazensis and Zanha golungensis. This, I feel, is an area that all efforts should be made to visit. Mr. Chase did suggest to me that sometime in March or April would be the best. This would have to be a week end trip.
WHIT MONDAY TOUR OF THE MAKABUSI WOODLAND
The other societies did not take advantage of the invitation and it appears we must rely on our own efforts. Flu hampered the distribution of notices to some schools. The modern trend of science education is “Go and find out”. Members might mention to teachers they meet that here is a potential valuable facility.
The deterioration of the veld is news today and the area could also be used to explain some of the basics to towns people. Why not take your friends to see the process of degradation?
MAINTENANCE OF FERTILITY IN THE VELD
Some of our readers may have heard in the last NRB broadcast, extracts from Allan Savory’s address to the recent Veld Conference in Bulawayo. Of interest to us was his stressing of the importance of trees as builders of the soil. In our climate they perform the essential functions of a) bringing up minerals from depth, b) providing litter; c) encouraging termites to bring clay to the surface and d) providing food for animals during the dry season and droughts.
We have alluded to these functions of trees in previous notes and hinted that they merit study, but the suggestion drew no comment from Agricultural Research, so we make no apology for raising the subject again. In brief we would like a scientific explanation for the phobia of trees. No one disputes that the removal of excess bush and trees, particularly the aggressive species, rapidly increases the amount of grass, but what is the long term effect? The other question to which there is as yet no complete answer is what are the reasons for the change over much of our veld from open savannah of mainly useful browse an fodder species to a dense almost worthless scrub woodland. Is this Nature’s attempt to restore soil fertility?
Those who favour the elimination of trees should study those down lands of the Eastern Border on which there is good evidence of a fairly recent evergreen forest. Animal life of all kinds is at an absolute minimum, the grass cover is thin and poor, everywhere sheet erosion is evident, and the streams are almost sterile. It would seem to provide the answer to the first question.
SALISBURY’S VANISHING STREET TREES
In the Avenues the absurd pruning of trees into grotesque top heavy shapes continues. Trees which were over pruned in recent years have made long straight shoots where large branches were removed and the combination of contorted boles surmounted by their poles has a place only in a witches garden.
It is all being done in the name of improvements to street lighting. Granted far too few species were planted and after 40 years almost without exception, they have grown too large and have several defects as street trees. The replacement of single dwellings by blocks of flats has brought other problems. Most of these mutilated trees will soon die so why has no interplanting with replacements been commenced?
Yours sincerely,
Douglas Aylen, President
Tree Society of Rhodesia Newsletter July 1969
Dear Member,
SALISBURY’S STREET TREES
The Manager of the City’s Amenities Department, Mr. Colin Knaggs, disagrees with me that Salisbury stands in danger of losing its reputation as the City of Trees. Before going further I must state that I admire his loyalty and the of his staff. I have had to get my information from other sources and by inspection.
Mr. Knaggs inherited a legacy of a small number of species of over street trees whose pruning had been neglected when young, that is in the older parts of Salisbury. When the trees were planted the present volume of traffic and the increasingly dense population in what were then quiet streets could not be foreseen, but now these trees, usually with multiple boles or low large branches, interfere with street lighting and parking or shadow the lower floors of buildings erected close to the road, these have to be pruned. Others which stand in the way of widening the tarmac and easing off corners have to be removed. The Toonas are all dying, and also have to be removed. The old Flamboyant have extended too widely at a low level. After the pruning we will scarcely be able to see the flowers on the tops of the tallest Jacarandas. The Spathodeas have done well where conditions are favourable but it seems that in places these eventually will be pruned to a top canopy.
Examination of many trees from which thick branches were removed some years ago shows that rotting has commenced in some of the wounds. There could well be a buildup of disease and borers. In time infected trees will become dangerous or die.
Over the last few years many trees have had to be removed, a few more are due for removal. Some will die or become dangerous. Most of those that remain will carry their flowers high above our heads. There are new streets to be planted now and in the future. The main highways through the commonages and the Civic Centre ideally need many thousands of trees, and for replacements and new streets several thousand will be needed. All these trees will require raising to a larger size than the usual transplant, and more protection and aftercare than is needed in a private garden. I need scarcely add that the shaping of a young tree in an exposed place is a far more exacting job than the pruning needed, if any, of a tree growing in a sheltered place. As far as I can tell Amenities has about one tenth of the facilities and funds needed to make Salisbury really a City of Trees.
PRUNING INDIGENOUS TRANSPLANTS: FROST REGROWTH
Recently several members have asked for advice on these subjects. There has been advice in the Press and on the Radio recently, and there are instructions in books on gardening. I will restrict myself, therefore, to some unorthodox suggestions based on my observation.
1.Young trees cut down by fire or frost: The many shoots which spring from the ground should be reduced in number over a period of several years. Remove the extreme tip from any competitive shoot.
- Bifurcated trees: Remove about one third of one “leg”, prune it lightly the following year. The unpruned leg will straighten and become the bole and the pruned one a branch.
- Transplants making a vigorous growth: Never prune to a single stem. Take off only the tips of low branches, waiting several years until the tree has a bole before removing them
- Transplants which form a protective thicket. This is often the habit e.g. Acacias. Tip only the longest branches, do not try to convert one of them to a future bole.
- Removal of lower branches for a tree. If possible prepare for this in advance by very light pruning of the branch in order to reduce its growth. This avoids a sudden stimulation of other branches and shoots from where the branch was cut off and also ensures a small wound which will heal quickly.
- Removal of larger branches: Do not cut flush with the trunk but allow a little for the increased in girth around the wound while it is healing. This avoids a hollow which slows down the rate of healing, also the small pit which sometimes appears at the centre is favoured as a means of entry by borers.
- Trees not growing vigorously. If the branches of any size must be removed recognize that you may be hastening the death of an aged or diseased tree.
- Scrub re-growth: this progressively over a period of up to 10 years, but first get advice from an authority on indigenous trees as to which saplings or what may appear to be scruffy bushes, to be the final trees to be kept, and place a marker by each of them.
Yours sincerely,
Douglas Aylen, President
Tree Society of Rhodesia Newsletter August 1969
Dear Member.
August 17th: Sinoia Caves National Park. Leaving from Reps Car Park at 0830. Full cars can proceed direct, sign post from entrance gate.
FORUM: “THE ROLE OF TREES IN NATURE, IN TOWNS AND IN INTRODUCING SCIENCE”
October 20th at 2000 hours in the Lecture Theatre of Ranch House. This is an airy cool building well suited for October, ideal for the purpose and with plenty of parking.
The title of the Theme and the three talks is tentative as I am leaving the final choice to the speakers. Subjects and speakers are:
- “Man’s impact on the veld with special reference to Trees, Grass and Erosion” by Dr. Brian Walker, Lecturer in Ecology, Department of Biological Sciences.
- “The Aesthetic Use of Trees in Towns” by Lynn Driver Jowitt, a Salisbury architect
- “The Educational Value of Urban Nature Parks and Sanctuaries” Keith Coates Palgrave is keen to give this talk but may be on leave, in which case a confrere will take his place.
Natural History Course for “Housewives”. I have agreed to assist in planning this course, one of a series. There will be nine sessions on Wednesdays, commencing on the 24th September at 1000 hours at Ranche House College. It is hoped the series will appeal to Garden Club and W.I. members.
The programme includes the evolution of trees, benefits of trees and grass, birds, wild flowers, degradation of the veld, origin of weeds and the food-chain (micro-organisms to birds and animals). The 2nd and 6th sessions will be excursions.
Extra Excursions: For the benefit of those attending either the Course or the Forum there will be two Sunday morning excursions, one will be to demonstrate the use of trees in relation to buildings and also the street trees, while the other will be to the Makabusi proposed Nature Park and Bird Sanctuary. Dates to be announced later.
An Introduction to Natural Science: One of the main objects of our present projects is to supply parents not necessarily members, with the means of interesting young children in Natural Science. We hope this will induce the parents to join us or a similar society now, and the children will later become Student members, 5/- a year. So please talk about these events to your friends. Have you passed on “Holidays in the Veld” to a child or a parent? Could I please have some written comments to follow the verbal praise for this type of publication.
BULAWAYO’S RIVERSIDE SCHEME:
Bulawayo is lucky that its river is not a handy place into which to discharge treated sewerage water and so create the usual problems caused by this practice. Instead use is made of this water, some of it being pumped via redundant water mains to playing fields and parks. Added to the benefit of economy of water is the advantage that the water is a weak fertilizer.
This has made possible amongst other improvements the development of the land along the Matsheumhlope River and the Bulawayo Spruit. A Bulawayo correspondent has informed us that there is increasing local pride in this wonderful effort and that from the number of inquiries made by Salisbury visitors, it is attracting considerable interest. A competent observer who knows well both cities has written “how much could be done there (Makabusi) with remarkable little expense if the job were to be tackled in a similar fashion.
There has been a tendency to belittle suggestions of impending problems of flood water in the Makabusi so an item in the Salisbury Times of the 27th June is of interest. The Old Gatooma Road between the Yellow Orchid and Sherwood Drive is at times impassable by cars due to flooding. Extracts read “as the area develops on the catchment side, so run off is tremendously increased…” A spokesman for the City Engineers Department said they were well aware of the problem. I can remember the culvert being made adequate once before! In the Sunday Mail of the 6th July, Stella Day discussed the Makabusi under the heading “A beautiful dream while it lasted”. Let us hope the dream comes true. Here is an account of Bulawayo’s effort.
“Initial water course improvements through industrial areas consisted of canals with concrete inverts and granite pitched sides. Alongside these canals suitable riverine trees have been planted. Away from the industrial areas lengths of watercourse have been re-aligned, re-cut to a trapezoidal cross section and planted with kikuyu grass which is kept permanently short. The effect of this protected cross section during the rainy season is that the velocity of the water is reduced and stream bank damage has been eliminated Two small dams one of 1 million gallons and one of 5 million gallons, have been built at suitable points to aid river control. Further upstream two old dams, the Hillside Dams, which were built around the turn of the century, have been discreetly developed. These are situated amongst granite kopje country and whilst keeping the natural flora, planting grass and introducing additional indigenous flora have turned this into a natural area which caters for anglers, climbers, walkers and those of more mature age who merely wish to sit and contemplate.
The development so far carried out along the river valleys may be catalogued as follows:
- Recreational area at headwaters of Matshumhlope in adjoining Town Council jurisdiction
- 300 acre reserve of Hillside Dams, a basically wild park with controlled improvements
- Riverside walk, with bowling green adjacent
- Sports Club, TTC playing field and two schools
- Golf club
- Boulevard in Industrial Area
- Park strip consisting of dam at head riverside walk, four schools playing fields, swimming bath caravan ark, two parks theatre and museum grounds, child welfare centre, 2 bowling clubs, 3 young people’s clubs, 6 sport clubs, second dam.
- On another tributary, one school and one golf club
- On another tributary, beer garden and open space in front of hostels, open space through house and flat development in African townships, sports field, allotments, parks nursery, cemetery.
These valleys are frost prone; clearing of undesirable vegetation has taken place, grass planting in areas under municipal control has been almost entirely with kikuyu and tree planting in supplementation or in replacement of existing specimens has been done in an informal manner.
Other urban centres are now beginning to adopt this method of urban riverine development to the conditions in their own areas.”
Pruning and Care of Trees: I forgot one matter last month, which is, the need to prevent termites working on pruned tree as they are apt to take off a layer of wood from an unhealed wound, even working a coat of protective “paint”.
Arboretum: The brilliant red Combretum microphyllum and a Cassia singueana along side it were both in full flower. Within 50 yards of this spot on the road I found nearly 50 different indigenous trees. Some thinning and ample labels are needed here. Don’t leave it all to the very few please!
Yours sincerely,
Douglas Aylen President
Tree Society of Rhodesia Newsletter September 1969
Dear Member,
We have two means of communication with our members, this Newsletter and the Rhodesia Science News. Before writing this letter I like to see what is in the News so that I can comment on topics and avoid possible repetition. However, at the time of writing, September 2nd, I have not seen the August News.
Another difficulty is the irregular arrival of “Trees in South Africa” which we post on to members who subscribe 10/- a year. This excellent quarterly is available only to members of the South African Society and, by courtesy, to our members. In this case not only is publication usually late but gremlins get into the dispatch department and our bulk order arrives in portions at intervals. We have even had back numbers instead of the current issue. At last we have received the full number fairly promptly and subscribers should receive their current copy shortly.
September 21st. McBeans’ Plot. Trees. Water Conservation and Ground water replenishment. Under unfavourable soil and rock formation conditions the McBeans have restored their bore hole water supply. A short talk by an expert on the subject. Mrs. McBean will provide tea from 1030 onwards. Bring your lunch and spend the afternoon if you wish.
Please note. Visitors are welcome at all activities. Are we giving you what you want? If not, please say so. Does the 3rd Sunday of the month suit you?
The outing to the Sinoia Caves: There was a good turn out of local members but very few from Salisbury. The trees around the sink holes are most interesting, in fact, a remnant of another era. I and several other members were disturbed to see that the picnic and camping sites had been made right alongside the holes and already some rather unusual trees are showing the effect of trampling of the soil and the lack of a mulch of grass and tree leaves.
As a result I submitted further written evidence to the Commission of Enquiry on Wild Life and received a reply which indicated interest. Much of my previous evidence had been on the need to make a decision in each case on the function and purpose of a Park. An area of land can serve only one form of use. Obviously one cannot have a Lido in a sanctuary, but equally an imbalance of game harms the vegetation. Tourist wish to see only large game really with the maximum of comfort and the minimum of effort and so tarred roads are made, strips burnt, artificial waterholes established and chalets and hotels built.
At the Caves the trees in the camping area have been thinned for size, not selected for species and where trees of a suitable size were lacking only exotics have been planted. The camping and picnic site should have been made 200 yards away and the vicinity of the sink holes treated as we did the Arboretum. If such use is made of the place the trees, except those within the holes, will suffer from the results of the trampling and moving and, as always the most interesting specimens will die.
Lecture by Professor Petrides of the Commission of Enquiry: “Conservation of Wildlife”. This most informative lecture included Plant Life mainly trees and I was sorry that so few of our members took the opportunity. The clinical symptoms of starvation of animals may not have been of direct concern to us but everything else, including the questions and answers was.
At the conclusion of the evening Mr. Aitken Cade, Chairman of the Wildlife Society who arranged the lecture, said that he proposed to hold a Forum soon on “Tourists and Conservation”.
Important Announcement: The major scientific societies of South Africa, with the Rhodesian Branch of the Geological Society of South Africa acting as hosts, have invited our Society to the 11th Alex L. Du Toit Memorial Lecture which will be delivered by Dr. Edna Plumstead on “Three million years of plant life in Southern Africa.” Southern Africa has the longest record of plant life found anywhere in the world. The character of the fossil floras is unique. The plant sequence will be traced with illustrations and the environmental conditions and contemporary faunas will be discussed.
Dr. Plumstead is renowned for her work in this field and is one of South Africa’s leading authorities on coal.
The lecture will be held in the Lecture Theater Geological Department University College of Rhodesia on Wednesday 17th September at 8.15 p.m.
Yours sincerely,
Douglas Aylen President
Tree Society of Rhodesia Newsletter October 1969
Dear Member,
October 20th 8 p.m. Ranche House, Rotten Row. FORUM “The Role of Trees”. I am pleased to be able to inform you that the Chair will be taken by Dr. Iain McDonald, President of the Association of Scientific Societies in Rhodesia.
Past Events: The Geological Society was very pleased at the good attendance at the Lecture by Dr. Enid Plumstead “Three thousand million years of plant life”. Not only did we have the biggest number of any other Society present but it was much appreciated that we gave advance notice of numbers. This lecture will appear in print in some months time.
The outing to Tomatin, Col. and Mrs. McBean. This was a very enjoyable morning. Dr. Peter Worzel gave a most interesting talk on the various forms of occurrence of underground water and its plotting by Geophysical Survey and an electric current machine. He also described the use of dissolved radioactive elements from hydrogen bomb tests for the tracing of the movement of inflow.
We then inspected the very complete measures which the McBeans have undertaken to ensure that all rainfall is trapped and caused to infiltrate. This work and the talk certainly merit a complete account, with diagrams; for public distribution. I am hoping this will be done as both subjects are quite beyond the scope and facilities of one of these Newsletters. A device for rapidly measuring the depth of water in a borehole was also of great interest and deserving as a subject for a Bulletin.
After which the party wandered around to look at a considerable selection of interesting planted and naturally present indigenous trees. Col. And Mrs. McBean must be congratulated and thanked for a great deal of preparation for easy viewing of the water conservation measures and for flagging aces of interest and labeling the trees.
The Ranch House Course: Nearly thirty people attended the first of the nine sessions and a few more will be joining later. This makes the effort worthwhile. The Course is part of the general scheme to waken interest, particularly amongst parents. It is becoming ever more necessary in this age of science that the children commence school, even nursery school, with a desire to observe, deduct and learn matters scientific. Our attempts are supported by lecturers at the university, one of whom told me he was shocked to find that the youth of Rhodesia knows no more of natural science than those living in large dense urban areas in Britain. The Forum, the Makabusi Scheme etc. are all complementary to this effort to improve matters.
What we can do is no more than a sample of what should be done. The number of subjects with which we can deal is limited. We have stretched “Trees” to include some aspects of Plant Ecology. I would like to suggest that there is scope for the other Societies and that with their help the Ministry of Education might well run a series of vacation courses for teachers, as the few who I know have expressed disappointment at not being able to attend during the school term.
Yours sincerely,
Douglas Aylen President
Tree Society of Rhodesia Newsletter November 1969
Dear Member,
November 16th. Dr. and Mrs. Murray’s Plot, Goromonzi. “Veld deterioration and Recovery”
6th December 0900 to 1700, Open Day at Botanic Garden. Address 0930. Tea at 1030 and 1530. Let us demonstrate our support.
FORUM ‘THE ROLE OF TREES’ I expected that the hall would be packed and I think it would have been if people had realized how interesting the evening would be. Instead it was hardly half full. Not only did we think it would be of great interest to all our members but we also sent invitations to quite a number of other Societies. Can I emphasize that the Committee endeavours to arrange activities that will be of considerable interest to the greater number. So if in doubt, trust us.
One of the objects was to let the public and the other Societies know how wide are our interests and the need for parents to interest children in natural science at an early age. It was, in fact, a miniature symposium at a general public level and in his opening remarks the chairman, Dr. Iain McDonald, congratulated the Society on its initiative. Myself, I hope it provided a sample or example of what the other Societies might do.
MAN’S IMPACT ON THE VELD: Dr. Brian Walker commenced by saying he prefers this title to the stated one of the Role of Trees in the Veld as though he would deal to some extent with the latter subject, trees cannot be divorced from the ecology of the veld.
The advantages of trees are they produce a) a micro climate, a more equitable local climate and b) a great bulk of plant matter, c) under trees there is a definite and large community of plants and a great diversity of animal life d) to some extent they replenish the soil with minerals from depth e) they provide shelter for stock and game.
The big disadvantage of trees is the competition, mainly water, with grass. This had influenced the desire to destroy trees. Except for a very few small “relics” all our veld has at some time or other, been manipulated by Man. In discussing what the original veld was like one had to decide whether the time meant is prior to white occupation or far back in the early Stone Age. Man’s stock and cultivation had already wrought big changes before the white man’s arrival. The combined impact had caused profound changes.
In virile veld the four important factors are: the consumers, the predators, the decomposers, bacteria etc. and the “a-biotic”, mineral plant nutrients, energy. If any of these is not present, did not function, a severe restriction or bottleneck occurred. Production is dependent on the rate of the nutrient cycle. In a woodland all “tropic levels”, canopy, mid-stories, surface plants, must be used. For example, absence of light stopped metabolism, failure to be decomposed locked up nutrients.
On open ground lack of utilization of plants and grass results in a thick cover of dead matter which stifles all growth. This senescence could be prevented by the introduction of a new force i.e. intensive use or fire. Firing of a long accumulated dense mass of dead vegetation is harmful, as the soil is left bare and exposed to sun, rain and erosion. There is a paucity of plants, perhaps ill suited to the violently changed conditions.
In nature there is a numerous and diverse population of animals which utilizes all plants which prevent senescence. Fires had always occurred and we had fire-climax vegetation, but evidence of the previous extent of woodlands and forest appears to indicate that in the past fire was infrequent. Fire is a useful tool in veld management if used with care. Grazing by cattle had prevented senescence but it also had encouraged bush and to overcome this problem Man had introduced more frequent fires, it then appeared necessary to fire regularly. Annual burning resulted in low productivity and absence of a protective cover to the soil. Then there was not enough material for a fire which would reduce the bush. With correct management a fire every three years is sufficient to control bush. The ecotones, zone between woodland and open grassland, with their variety of plants, and therefore importance, depend on fire. Too frequent fire reduces their area.
The biggest impact on our veld has been made by over use, i.e. overgrazing but not necessarily overstocking, in the lower rainfall veld areas. The veld here is brittle and the condition of most of it is now serious. The high veld has undoubtedly changed but in comparison generally has not been degraded.
Grazing by cattle causes changes in the veld because Man has converted multi species use to single species use. In nature everything is eaten by something but cattle eat almost solely grass. Not only do cattle favour a limited number of grasses, but they tend to favour certain patches and will return to re-graze new shoots. Small antelope are more inclined to nip of a piece here and there as they move. As a rule game graze the grass fairly high, that is above the lower growth buds which rapidly form new leaves soon able to restore food reserves to the roots. Cattle graze low, removing the buds, and thus there is a delay in the formation of leaves. They may return several times at short intervals and eat the new leaves as they appear, in which case the roots are deprived of food. This is believed to be the reason why that most nutritious grass, Themeda triandra has been eliminated from many areas in Southern Africa.
Buffalo graze only knee high, provided there is sufficient grass, and the grasses they favour have become adapted to this, but cannot tolerate low grazing by cattle. After grazing grass must be permitted to recover but the interval of rest should not be beyond the period when the rate of growth is falling off, otherwise it becomes moribund. It must not be regrazed until the leaves have been able to restore food to the roots. The period of grazing should be limited because of the tendency of cattle to return to favoured grasses or patches. Damage to grass is not limited to the grass, but affects everything else in the ecosystem.
Damage can be done to the veld, by overgrazing, by half the number of stock that could be carried successfully by correct management. Poor management means less virile grass, less bio mass less cover and litter on the soil and thus the creation of a hardened surface which reduces infiltration of rainwater which further reduced productivity. The veld is then on the down grade.
Man has confined a single species to a restricted area for a period of time of his choice. In places he has physically removed or reduced the trees or unwittingly increased the bush. There is still much to learn on grazing management and we have scarcely looked into the advantages of running game and cattle together. Elsewhere some experiments had resulted in big increases in the yield of meat while maintaining the virility of the veld. However much more experimentation and study are needed.
Discussion followed on the effects of the removal of trees. Dr. Walker said it had no general effect on rainfall but there might be changes in the effectiveness of the rainfall. It was suggested that trees reduced frost and also wind and thus evaporation. Dr. Walker said that there is really no information on the evapo-transpiration of the indigenous trees. He added that nothing is clear cut in nature.
However, the removal of trees on skeleton soils, shallow, lacking definite top soil on the basalts and parageiss where rainfall is low is deleterious. Grass is there sparse and in drought years insufficient to give any protection to the soil and animals must rely on browse. Under such conditions if trees are removed there is a lack of food and also erosion occurs. Mixed cattle and game appears to be the solution for these areas.
During the course of the lecture Dr. Walker showed colour slides which demonstrated the improvement in grass cover which resulted from the removal of trees in areas of moderate rainfall and fair soils. Others showed the result of burning and mowing frequency experiments, and the result of overstocking.
Summaries of the other two papers will be given in the next newsletter.
Yours sincerely,
Douglas Aylen President
Tree Society of Rhodesia Newsletter December 1969
Dear Member,
December 6th. Open Day Botanic Garden. Opening address 0930. Tea will be served at 1030 and 1500 hours. Please advise numbers attending.
December 15th 2030 hours. Ranch House. Film of the Haroni Lusitu Schools Expedition and a lecture on dwarfing trees by Mr. W. Bollman. You are particularly asked to bring guests to the above two activities.
THE OUTING TO DR. AND MRS. MURRAY’S, GOROMONZI. This outing could be said to have been a follow up to Dr. Brian Walker’s lecture at the Forum, and to others at the Ranche House Course on Natural History. The weather was perfect so it was disappointing that more people did not come. After an excellent tea provided by our hosts the President gave a short account of factors which cause degradation of the veld and measures that should be taken to assist recovery.
The property of some 300 acres of granite sand veld consists largely of kopje and steeply sloping land. Most of the flat land is paddocks for horses, while pockets of soil carry small plantations of patula pine or are being planted to this tree. Over a long period there must have been sporadic patch cultivation and more recently heavy over grazing. The veld is now enjoying a rest and the moderate sheet erosion from which it suffered has almost ceased.
The veld was examined on a short walk lead by Mr. Lightfoot who interpreted the signs on the ground. One can only guess at the composition of the original savannah woodland but possibly it consisted of mountain acacia, mnondo, mukwa, Albizia antunesiana and Monotes glaber. On land free from rocks these had been replaced by Muzhanje, which this year has suffered from a double plague of caterpillars which has completely destroyed the foliage on this and a few other trees in the vicinity.
Evidence of past erosion and measures for restoring grass to bare areas was discussed. It was considered that incipient gullies would heal if run off could be reduced by restoring the rate of infiltration, and capacity for holding water in the soil. Natural mulch would effect this and improve the resent thin covering of grass. The superior grazing grasses were restricted to slopes protected by boulders but possibly will spread slowly.
Of great interest was an old iron smelting furnace of most unusual design and in extremely good condition. It was sited beside a pit which we presumed contained a deposit of refractory clay. An examination might be rewarding.
Mr. Trevor Gordon then led a tour of the relatively undisturbed areas to see the trees, ending by scaling a low kopje of large granite boulders by way of easy paths. The kopje is notable for the views, we could see gum trees at Marandellas and the granite domes of Shamva, Mrewa and Chinamora, while almost at our feet was a glorious view of the Nora valley Some of the trees on the kopje are Ficus natalensis, Allopylus africanus, Canthium lactescens Euclea natalensis, Maytenus heterophylla and Maytenus undatus and Tricalysia angolensis.
THE FORUM (contd) ‘TREES IN TOWNS’ L. DRIVER-JOWITT
This most interesting lecture was an artist’s approach to the composition of the picture of trees and structure. The essentials could be summed up as ‘viewing points’, ‘the focal point’, ‘frugality’ ‘variety of form and colour’, ‘balance’ and ‘the third dimension’.
In a painting the view is constant but in actuality it is seen from changing angles within the picture, with changing light and cloud, seasonal changes of colour and, in time, the increasing size of the trees. A photographer can obtain effects and take his picture from normally inaccessible points thus achieving a picture not available in reality to the public. Planning must take account of the various stand points from the vista will be seen.
Trees must be tied to a focal point. This was demonstrated by adding trees to outline sketches ranging from a farm gate to road bridges, houses and public buildings. The effect was obtained by an economy in the use of trees. Positioning and for are important, for example a curved line of trees of equal height has an ugly hollow back when seen from the centre. Provision for seasonal changes, a variety of form and colour and an outline which harmonizes with the building are cardinal.
Solid screening is ugly and frustrating as one wants to know what is beyond and to see into the trees. A back-drop must have a balanced outline or balance the outline of the buildings. In either case a few trees must be brought forward to give a third dimension.
In parks and open spaces the maximum number of vista points is obtained by irregular placing of ‘random’ groups of several species, designed to lead the eye to features of interest. Riverbanks and the verges of lakes are major attractions in many towns. Long sweeping views across lawns can be obtained by using trees with tall boles and bordering the area with a somewhat open screen of trees of different shapes.
The grid plan of streets, Mumford’s ”every street a carriage way leading nowhere” gave no opportunity for focal points except perhaps by marking large circles some of the cross roads, though, for example, the “hanging tree” could be a focal point. Such breaks overcome the monotony of long avenues, but if not possible short lengths of different trees or mixed plantings obviate monotony, season bareness or lack of colour, as well as the otherwise inevitable wholesale replacement. Different shades of green can be most effective.
Salisbury has the opportunity for dramatic planning at the Civic Centre, but unfortunately it is not the centre of gravity which is Cecil Square. The idea of a mall along Baker Avenue is a good one provided a bold scheme of tying the Square to first Street with some feature there was undertaken. Other cities have their famous views and picturesque squares which they exploit for advertising purposes.
Designers should give the same consideration to trees as to their other materials consulting the relevant experts as well as the town planners and engineers.
In reply to questions, Mr. Driver Jowitt said there is a wide variety of indigenous trees of different beautiful shades and colour of leaves and flowers. When clearing sites a sufficiency of trees should be left, the effect being achieved by removing unhealthy and surplus trees.
SCIENCE EDUCATION AND THE ROLE OF NATURE PARKS Keith Coates Palgrave
Mr. Palgrave commenced with a concise but very comprehensive account of the origin of modern science teaching and then described the method of setting pupils to find out. One of the projects was to cross breed fruit flies. At the end of the experiment and having reached a conclusion the pupils were told that they had re-proved Mendel’s Law, in contrast to the old method where they would have been given the Law and told to check it. Whereas Mendel’s experiments with peas took years those with fruit flies took only weeks.
Mr. Palgrave was always looking for facilities for projects and woodland such as the Makabusi would provide many opportunities. If there was a need by senior schools for nature parks, it was tenfold for junior schools.
NGESI NATIONAL PARK: 35 miles west of Featherstone, Salisbury Enkeldoorn Road. Access also from Umvuma, Que Que, Battlefields, Gatooma and Hartley. We are indebted to Mrs. McBean for the following account.
“At the end of October we spent five nights in a delightful reasonably priced Swiss chalet type cottage on the banks of the Ngesi Dam. We watched cormorants on the rocks, witnessed the brooding of a pair of paradise flycatchers, an excellent example of shared parental responsibilities, and enjoyed a mocking chat tapping at the window in answer to our whistles.
The Warden provided us with a check list of the trees in the Park which we found most useful and instructive. There are interesting and beautiful walks along the edge of the water as well as in the well wooded veld, where we caught sight of a few buck and many guinea fowl.
The roads are well maintained so that it is a pleasure driving in the Park. We have never seen so many large Monotes glaber or Burkea africana, then dripping with their catkin like flowers. We thoroughly enjoyed our holiday in the peaceful wooded surroundings. Besides the four pleasantly sighted guest cottages there are camping facilities and excellent fishing.
Yours sincerely,
Douglas Aylen President