TREE LIFE

July 1983

 

MASHONALAND CALENDAR

Saturday July 2nd  : Botanic Garden Walk.  Meet at 1045 for 1100 hours.

Saturday July 9th : Binga Swamp Forest, Arcutus Road.  We plan to weed from 0900 to 1230 hours, see article inside for further details.  Turn left off Arcturus Road at about 26 km peg and then travel for about 1 km on a gravel road to the forest.

Sunday July 17thRaphia Palm Botanical Reserve at Palm Block beyond Mvurwi  (Umvukwes).  The Harare and Ayrshire Branches will be joining up to visit this unique area of Raffia palms on the slopes of the Great Dyke.  This is a protected area where permanent water creates a “soak” or “sponge” which supports this relict population.  The atmosphere felt as one walks amongst these giant palms is unreal.  One leaf can measure over 50 feet, so this plant has the largest leaves of all plants.  Please see also Benedicta Graves’ write up on the Dyke which appears later in this issue.  We will also have a look at some of the other vegetation in the area, probably on a farm on the Western side of the Dyke.

A bus has been booked which will leave from Monomatapa at 0800 hours sharp.  Fare $15.00.

 

BOTANIC GARDEN WALK, 4TH JUNE 1983

Bequaertiodendron magalismontanum. Photo: Bart Wursten. Source: Flora of Zimbabwe

Bequaertiodendron magalismontanum. Photo: Bart Wursten. Source: Flora of Zimbabwe

With the approach of Winter, Tom Muller wisely decided to show us an interesting evergreen family, the SAPOTACEAE, and how rewarding it was to see some well known trees in the context of the family to which they belong.  Perhaps we should examine the family features while visualizing the well known stem fruit, Bequaertiodendron magalismontanum.  Like all SAPOTACEAE this plant has simple, alternate leaves with an entire margin.  They also have a milky juice.  A further feature we saw repeatedly amongst the SAPOTACEAE was the distinctively elongated young leaves coated in reddish brown hairs and characteristically angled downward from the growing point during early development.  B.magalismontanum often has an emarginated tip to its leathery leaf.  The common name, stem fruit, refers to the fruit that is attached to the old stems.  Generally the SAPOTACEAE have brightly coloured succulent berries which are decidedly edible to people and animals alike and B.magalismontanum is no exception.  This species is frequently found on granite kopjes but enormous specimens up to 35m occur alongside Garcinia in the forests above the eastern tea estates.  In low altitude forests it is often a 10 m under storey tree.

The first plant we examined, Afrosersalisia kassneri (Tulestea kassneri) is a rare under storey tree beneath Newtonia in the quartzite hills of the Makarubeni-Haroni valley.  Together with all the SAPOTACEAE features, especially the brown hairy growing tip, A.kassneri has attenuate leaves where the veins arch near the margin but neither loop nor run parallel.

Moving further into the forest section we came across Bequaertiodendron natalense, a very similar tree to B.magalismontanum but having a pointed or attenuate leaf tip.  Although originally collected in this country by Swinnerton near Mt. Selinda, it was long thought he had muddled it with his Mozambique collection until it was rediscovered and found to be quite common in some areas, especially in the valley burial grounds around Chipinga and in the Vumba behind White Horse Inn and Mermaid’s Grotto.  Besides the drooping of the juvenile leaflets it illustrated a further SATOTACEAE feature where the leaves are crowded at the ends of the branches.  The orange fruit were still too green to sample.

We were able to examine the solid trunk of a Chrysophyllum viridifolium that disappeared into the forest canopy, with characteristic silver grey snake patterning on the bark which corresponds to an equivalent red and white slash pattern (which we refrained from testing).  Apparently the stem in this and other SAPOTACEAE can become tightly fluted.  Later we examined leaves of a smaller specimen in a more exposed habitat and noticed the close lateral veining with a characteristic sub-marginal vein.  This tree occurs as a 30 – 35m sub-canopy tree in mature forest at 1000 m near Mt. Selinda and in the Vumba.

Syzygium guineense subsp. gerrardii. Photo: Bart Wursten. Source: Flora of Zimbabwe

Syzygium guineense subsp. gerrardii. Photo: Bart Wursten. Source: Flora of Zimbabwe

The other Crysophyllum, C.gorgungosanum, initially resembles Bequaertiodondron with the brown furry under surface to the leaf that is thought to help the tree withstand drought.  We noted the tight fluting of the trunk and large elliptic leaf.  C.gorungosanum appears to take over from Syzygium guineense subsp. gerrardii at altitudes above 1500 m in the mature forest near the tea estates in the Vumba.  Excellent tightly fluted trunks can be seen on the path to Mt. Selinda’s big tree amongst the Craibia.

The large leathery leaves of Aningeria adolfi-fredericii are very quilted by the veins which are prominent on the under surface but the SAPOTACEAE features are still present; the brown hairs and milky latex.  The leaf is entire but some margins have a sinuous quality.

Despite extensive hunting on both specimens in the gardens we were not able to find any pallucid dots mentioned in Coates Palgrave’s “Trees of Southern Africa”.

Manilkara is an interesting genus, strongly illustrating the crowding of the leaves on the end of the branches.  The first species we examined, M.discolor, is a silver grey underneath (hence the discolor), although we found a few brownish hairs on the white growing tip.  This sub canopy tree is difficult to cultivate but occurs naturally in dry rain forests in the Haroni-Rusitu Valley and at Marahwa’s hill in Mutare.  The indigenous species, M.mochisa has a distinctive horizontal branching pattern somewhat like Gardenia with leaves to match.  The terminal rosettes of leaves had few hairs on this small specimen.  Apparently this can grow into a large tree in the dry lowveld particularly among the streams at Sengwa and other valleys to the north.

Inhambanella henriquesii. Photo: Bart Wursten. Source: Flora of Zimbabwe

Inhambanella henriquesii. Photo: Bart Wursten. Source: Flora of Zimbabwe

Cultivating plants in the Botanic Gardens has its problems and growing Inhambanella henriquesii has not been helped by local lovers who succeeded in flattening the small seedlings soon after Tom had planted them in their secluded forest habitat.  This spreading forest edge tree becomes an attractive red-flush colour in spring at which time half a dozen specimens can be detected on Mt Selinda.  The SAPOTACEAE feature of bunched leaves is extended in Inhambanella where the branches are also crowded together giving the tree a layered look.  Once again we noted the furry growing tip.

In contrast to the long petioles (up to 5 cm) of Inhambanella, those in Pachystela brevipes are short.  Yet again a reinforcement of the SAPOTACEAE features;  the flowers on old wood, milky latex, brown tip and bunched leaves and branches.  The leaf’s drip tip indicates the wet under storey closed canopy forest habitat in the Chipinga-Haroni-Rusitu valleys.

A frequently encountered member of the family, Mimusops zeyheri, illustrated the superior ovary of the developing fruit, which together with the free petals helps put the family alongside the EBENACEAE, Ebony family, the similarity between the fruits of M.zeyheri and the star-apple, Diospyros lycioides, is very significant in the order EBENACEAE.  Long petioles held the shiny dark green leaves onto this riverine and dry rain forest tree.  The most well known specimen being the lare tree within the walls of Great Zimbabwe, but also common at Victoria Falls.

We saw another species, M.obtusifolia which has a long petiole with much larger leaves, but very similar morphologically.  This species has been found in the Sabi Valley.

It is always comforting for me to see another Cape Peninsula tree and to learn that the white milkwood, Sideroxylon inerme occurs on anthills in the Triassic sands of Gona-Re-Zhou.  A different habitat to its usual  sand dune situation along the southern and eastern South African coast.  We noted the developing blue berries as well as most of the SAPOTACEAE features.

All in all a rewarding and stimulating morning, although we are really eating into Tom’s weekend being so long overtime, but thank you very much for the lesson, it will not all be forgotten.

-Kim ST.J.Damstra

 

VISIT TO GARAMWE  FARM,CHEGUTU, 19TH JUNE 1983

The trip to Garamwe Farm began plagued by gremlins.  There was no security guard, the bus was parked outside the Monomatapa, and, when we finally did get going, one member’s keys were left behind in the car park.

This jerky start was however merely a false start to one of the most enjoyable trips we have had for some time.  The drive down to Chegutu took about an hour and a alf, but we arrived at Garamwe refreshed by the sight of Cassia singueana (sinter flowering Cassia, along the way.  The dots of bright yellow made welcome relief from the otherwise dry  bush, now rapidly losing leaf.  At the farm house we were enthusiastically met by Olive and David Reoch and their daughter Lynette, and were led to the verandah of their thatched house for tea.  A number of enthusiasts from Chegutu area had laid on a tea which was not to be missed.  While pondering the wonders of farm house baking we wandered down the garden to see a most notable specimen of Hexalobus monopetalus, baboon’s breakfast.  We immediately missed our tree friend Dr. Ken Davey, now retired to the Cape, who would have been in paroxysms of delight at this specimen, certainly the largest that any of us have seen.  However, Meg’s exclamations were almost as overjoyed as those of Ken and she proceeded to point out to us the hard leaves in one plane, and the distinctively angled growing tip.  Only the remains of old fruit were present, and most of us have only second hand accounts of the delicious nature of the fruit, as monkeys and birds generally have it all long before any human arrives. Nearby was a large Gardenia ternifolia, formerly G.jovis tonantis, and a Ficus thonningii grown from a truncheon.  We could not agree on the reasons for the development of aerial roots from the trunk of the latter.

Ziziphus mucronata. Photo: Bart Wursten. Source: Flora of Zimbabwe

Ziziphus mucronata. Photo: Bart Wursten. Source: Flora of Zimbabwe

We then re-boarded the bus and soon began the mornings walk.  What a reward it is to sometimes arrange trips a god distance from Harare.  The area had a decidedly lowveld feel to it.  Bauhinia petersiana was everywhere in heavy fruit; its flowering season must have been spectacular.  Just across the dried water course we followed was a termite mound, adorned with a thorny Ziziphus mucronata and a large Albizia amara.  Having ascertained for certain that this was no Acacia we examined the minute leaflets to ensure that this was not  A.harveyi.  The leaflets, practically invisible to those a little long in the tooth and therefore long of sight, were definitely not the sickle shape of those of A.harveyi.  Most excising was the discovery of Berchemia discolor, last seen at Watkin’s farm, Chegutu.  We noted the pale cream veins on the smooth green leaf with its characteristic quilted appearance and the sulcate, grooved or guttered, petiole.

Crossopteryx febrifuga. Photo: Bart Wursten. Source: Flora of Zimbabwe

Crossopteryx febrifuga. Photo: Bart Wursten. Source: Flora of Zimbabwe

Wandering on, we were excited to find Crossopteryx febrifuga, the ‘crystal bark’, in considerable numbers.  An examination of the dried bark pulled from a tree, showed the reputed crystals glinting in the sun.  The bark is said to be poisonous and this species is one of the ordeal trees.

The area was rich in Combretum species.  Combretum apiculatum was common and responded correctly to the ‘slash’ test by displaying a yellow under bark.  Combretum colinum and Combretum zeyheri are difficult to separate by having a pink and orange red slash respectively, but the former was in unmistakable liver red fruit, so confirmation was unnecessary.  C.hereroense ‘mouse eared combretum’ was a special bonus with its small velvety leaves, and C.fragrans was in its best winter colours, and there were some good sized trees unlike the coppice we so often see.

There were Acacias a-plenty, something we do not have often in our part of the world.  Acacia amythethophylla was in heavy fruit and quite common.  A.rehmanniana with its velvety soft leaves and rusty red young branches gave way as we walked to A.gerrardii with its rather stark appearance and curved pods.  The stark appearance is caused by the leaves tending to come off close to the main branches, unlike A.karroo which we also saw and whose pods were of similar shape.  There were a good number of A.goetzii, many in pod.  I am certain that I saw examples of both the subspecies, goetzii and microphylla, but unfortunately I did not collect specimens at the time.

Adjacent to and blending with this mixed woodland of combretums, acacias and Brachystegia boehmii, was what we always look forward to – the mopane.  And what a stand of Colophospermum mopane this was.  The trees were still in almost full leaf and were loaded with fruit.  We were able to examine the vestigial third leaflet in between the two large ones and to open the pods to reveal the crinkled seed dotted with translucent dots of resin.

Commiphoras were well represented, although a little problematic with no leaf.  We certainly saw C.marlothii, the peeling bark, and C.africana with its finely peeling bark as well as C.mollis.

Cassia singueana was everywhere in flower, so one did not really need to see the ‘bee sting’ between each pair of leaflets.  Completing the first half of the circuit from the bus we came to a distinct patch of Dalbergia melanoxylon, black wood, dozens of trees growing close together.  On the far side of an almost leafless tree was almost dismissed by us as Lannea discolor.  However a few leaves bunched at the end of the branch gave it away as Sclerocarya birrea, formerly S.caffra, the marula, a tree we seldom see.  The thick branchlets ending in a blunt lump is reminiscent of Lannea branches, generally known a “dead man’s fingers”, but recently being called “E.T.fingers” for those who saw the film.  On the way back to the bus, hurrying under the impetus of the thought of lunch we passed a huge Pseudolachnostylis maproneifolia, duiker berry, and Pterocarpus rotundifolius, and, right at the road a super Cassia abbreviata, covered in pods 60cm long.

After being served a huge pot of hot farm soup by Olive, we packed into two vehicles to go to see a big fig tree.  This fig, Ficus thonningii was well worth a special visit.  It was enormous and had completely obliterated its original host, a mufuti, Brachystegia boehmii.  Whilst in the process it appears to have poured out on itself much as one layer of hot candle wax runs down over the previous layer.  The whole thing was a mass of sinuous roots, apparently splitting only to rejoin later.  Once the wonder at the fig had died down, we turned our attention to nearby trees.  In the shadow of the fig was a small tree which caused much discussion. After arguments in favour of Dovyalis zeyheri it was realized that it was Flacourtia indica in one of its many confusing shapes.  Some large Monotes glaber were heavy with their flower like fruit.  We heard them termed “helicopter trees” which is quite accurate as the seed does spin to ground supported by the hardened sepals.  Dick Petheram found an exciting specimen also in the shade of the fig.  It turned out to be Vangueria randii, another unusual find.  The most distinctive feature to myself was the petioles of the under surface which were very white against the green of the leaf.  I have seen no other species with such distinct white petioles.

Nearby was Psorospermum febrifugum.  It was Lola Irvine to pointed out the row of tiny black dots, resembling stitching, about the entire margin of the leaf.  Even where a specimen lacked the russet colour so characteristic of the Zimbabwean holly, these dots were obvious.

We returned to the house from whence we took one last short walk.  Some went behind the calf paddock to look at the Kigelia africana, which has somehow established itself down there, miles from the nearest river.

The rest of party climbed the kopje at the back of the house where they found Afzelia quanzensis, the pod mahogany, and Kirkia acuminata, the white syringa.  Gardenia volkensii, formerly G.spatulifolia, grew on the kopje.

After another quick cup of tea or glass of milk fresh from the herd, we boarded the bus and took leave.  Our sincere thanks to Olive, David and Lunette for giving us a truly wonderful day.  Thanks for all the hospitality, hot tea and soup and endless fresh chilled milk.  Also to Ann Bianci who brought so many delicious edibles and to all the other people from Chegutu who came to meet us and showed such interest.

-C.Haxen

 

BINGA SWAMP FOREST : A CALL TO ACTION

A NEGLECTED Princess Carabosse could not have found a more suitable plant to surround Sleeping Beauty’s castle than Mauritius Thorn, Caesalpinia decapetala.  The thick scrambling trailers climb and drape everything, forming a thick veil that only a decade ago mantled Binga Swamp Forest only 30 km from Harare on the Arcturus Road.  The large plant has small insidious thorns that get under the skin pulling one’s flesh into little tents.  Hearing from Dick Petheram how active the Tree Society was in playing the role of handsome prince hacking and burning away at the inestimable mass, I must confess the thought of the mammoth task deflates my libido towards any Princes Aurora.

Now the major job has been completed the princess, in the form of a magnificent gallery forest has emerged in all her splendor.  But not all that was sleeping has been quite awakened, a great multitude of seeds still lie dormant within the soil, and from this stock numerous seedlings take root and follicle forth each month.  A regular depilation of these seedlings that sprout up beneath the brachial boughs is required.  This gentle electrolysis can be a relaxing occupation for the very young and old, and so rewarding to sit back and see the roots of a few thousand young Mauritius Thorn.  Unlike the adult plant, juveniles have few thorns and are easy to handle and simple to remove but they grow rapidly and can flower and fruit within a few months if allowed to get away.  For the active who wish to play handsome prince, a few larger plants may still be found in selected patches.

Such a lot has been done by so many private people and weed control bodies that it would be a pity to allow this task to slip.  In May re received a poor response, so please try to come along.  We plan to work hard at it from 0800 hours to 1230 hours on Saturday 9th July.  If we come armed with flasks of coffee and tea we can provide a valuable contribution to this magnificent forest.

 

AYRSHIRE BRANCH : “THE GREAT DYKE FROM RAFFINGORA”

In the sitting room at Katawa there is an oil painting by Elizabeth Richardson entitled “The Great Dyke from Raffingora”.  It is this view, our view, which has prompted me to write.

Bundu Book 3 describes the Great Dyke as a “basin-shaped mass of igneous rocks … its course is indicated by a chain of hills which stretches from Sipolilo (Guruve) in the north to Belingwe (Mberengwa) in the south” it is a unique geological phenomenon.  From about the Mukwadzi river it is called the Umvukwe (Mvurwi) Range and this is our part of the Dyke.  It means many things to many people and possibly very little to a few.  Even if it is taken for granted it does affect our lives here in Raffingora, quite apart from the fact that it contains vast mineral deposits which provide wealth.

A glance at the hills prompts the first decisions of the day, what to wear – hat/jersey/raincoat?  “Maybe we should take the umbrella with us to town?”.  In springtime when haze and smoke hides the horizon : “It is going o be another scorcher today” and later in the year “They get all the rain, we could do with some”, a big sigh follows.  Attitudes to “The pass” vary, some of us may regard it as an obstacle on our route; a landmark time wise; and interesting place with climate and scenery all of its own, providing a welcome contrast to that back home.

There is evidence that Bush people inhabited the vicinity of the Dyke about 40,000 years ago –a sharp edged cutting tools struck from quartz impregnated serpentinite pebbles were found recently near Darwendale, other Stone Age artifacts occur at Zombepata in the Guruve area.  During the first 1000 years A.D. the negroid Bantu arrived and stayed.  Pottery found at Zombepata is called Musengezi ware, so called from the river which cuts through the northern Dyke, lots more of this kind has been found at Mutorashanga, it was used more than 800 years ago.  During the 16th Century Swahili, Muslim and Portuguese traders in metals, ivory and slaves, entered the kingdom of the Mutapa of the north, the land between the Hunyani and Mazowe rives.  Remains of a small dzimbabwe have been found at Zvongombe near Centenary (D.N. Neach).  Recent records show that commercial farming began close to the Dyke in 1918 and the first mining claims were made in 1926.

There is much to motivate inquiry into the Dyke; kloofs with palms, aloes, sponges, the huge “pool” at Ethel Mine, mtorolite, pig-rooting, how can crisp juicy apples be grown so close to the Dyke at Rhimbick, and where can information be found about the Mutoroshanga Protected Area?

On Sunday 17th April 1983 the Ayrshire Branch of the Tree Society met at Mutorashanga Club in order to have a look at the hill vegetation on Lone Cow Estate.  The poster advertising this event informed us that we would be going up Mt. Umvukwe. This was an error, this 5702 ft peak is in the northern heel of the Dyke enclosing the Horseshoe Black, a well known farming area.  On the Raphia palm excursion we should see Mt. Umvukwe on our return via the western side of the hills.

The Fraser Mackenzies, our hosts for the day, sent us off on wheels, on the Kildonan road along the west of the Range, then east through a pass to join the Caesar Mine road, here we turned north along the east of the Range, finally a rough track led us in a westerly direction up to the very top.  Quite quickly said but it took at least two hours.  We parked beside the geodetic beacon which is 5748 ft above sea level and more than 1400 ft above the countryside to the West.  AT this altitude the climate in cooler, wetter and more windy than that of the granite jokje country below.  Opinions differ about “gutu” on the dyke, drizzle and low clouds are distinctly different.  Frequently clouds wreath the summits where exposed rocks bear lichens, and some of the sheltered ones are moss covered.  The fern, Pelleae, testifies to the humidity.

Small groups mounted the 15 ft high platform on the beacon.  What a panorama!  It was easy to pick out the landmarks in the Ayrshire district; Monk’s Kop, Chiwe, and the jagged line of hills in the direction of the Ayrshire Mine.  Further away we saw Doma, Hunyani Hills, Mt. Hampden, Bindura and on the misty horizon the last mountains where the northern end of the Dyke drops into the Zambezi Valley.

Our angular tour in the morning proved to be an exciting experience.  Part of our ascent where the road followed a watercourse was delightfully shaded.  Further up it was the exact opposite, a radiator boiled and there seemed to be no water around until one of the Hendersons, prepared for anything, supplied enough to get us all on the move again to join the others already sipping G and T and dipping into their picnic baskets.  Shade was sought beneath dwarf trees.  Three generations of the Francis family sat under a mature Msasa which bore its pods at shoulder height, quite in keeping with the altitude.  The tour was of ecological value as four types of scenery were observed; firstly there were streams narrowly fringed with a wide variety of trees, shrubs, lianes, flowering herbs, grasses, reeds and ferns.  Secondly we found sparsely grassed slopes dotted with an occasional aloe, succulent shrublet or stunted tree.  Then we saw some hill tops and crests of ridges covered with woodland.  Lastly we encountered wide shallow valleys and depressions where moisture enabled the growth of grasses, different to those on the dry slopes.  Here shapely proteas grew dispersed amongst the very limited number of tree species.

Of course we noticed the absence of agricultural crops, this is due to the steep terrain, infertility, exposure to the elements and to the chemical elements below the surface.  Strangely enough there is not the amount of erosion expected, this is because of the surface is very rough with stones which are porous so the rain soaks in and there is not much run-off, with the result that the steep hillsides remain remarkably dry.  These conditions account for the paucity of flora on the Great Dyke as compared with that of other regions in Zimbabwe. With the exception of the vleis, there is practically no soil, the depth is rarely more that the length of a match box except where fissures occur in the rocks, where some shrubs and trees manage to grow.

The chemical elements below the surface need some explanation so as to understand the distribution of the vegetation we saw.  A greenish coloured soft porous rock called serpentinite is exposed on about 70% of the Umvukwe Range.  Its name has nothing to do with the lake in London’s Hyde Park, serpentinite is so called because it is sometimes mottled or spotted like a snake’s skin.  When the serpentinite which contains thin seam of chrome ore, decomposes by weathering it releases a formidable concentration of ‘mineral salts’ consisting of the elements magnesium, calcium, iron, chromium, nicked and aluminium.  It is interesting that plants and soils from the riverine forest at Caesar’s Pass and from a serpentine woodland on a crest at Mutorashanga Pass have been analyzed.  The conclusions reported in “Kirkia” Vol. 2 Part 1, 1978, stated “In the case of the riverine species the availability of water seems to be the main determinant of distribution.  Either toxicity  has less effect in this type of situation or the trees concerned have some degree of tolerance.”  Then where the woodland dominated by Brachystegia spiciformis, Msasa, occurs on the crest of a ridge, a lower nickel level compared with soils on the slopes below seems the most likely factor allowing the growth of trees.  More experimental work was needed to confirm these deductions.

Trevor Gordon drew our attention to woodland which resembled that of the granite soils of the farming area adjoining the Dyke.  These trees indicated the presence of Pyroxenite rock, which is very hard, non porous and on decomposition forms soils less toxic than serpentine soil.  Roger Barclay Smith writes “Where pyroxenite forms the foot of the Dyke it is possible to grow satisfactory crops right up to it.”  Reference to a pedological map would show whether this is the reason for the successful orchards at Rhimbick.

Explanation of the sponges follows on from the non porous nature of pyroenite and other fine grained rocks which in deep regular trough shaped layers, underlie the porous serpentinite.  This acts as a reservoir, it is here that rainfall is absorbed and stored.  Sponges are the source of the perennial streams which flow out of the Dyke.  Not all vleis are sponges and not all sponges are vleis!  Theoretically the streams should never dry up and the waterside trees should thrive unaffected by droughts.  What will happen this year?

The Dyke means many things to many people, to miners digging out chrome and asbestos, flooding must be an ever present threat.  Years ago people talked about damming the Mukwadzi within the hills, for obvious reasons it never materialized.  To the children who came with us these hills meant a physical challenge.  Peter Fraser Mackenzie to them under his wing and set them off at times intervals to climb 1000 ft.  They were not allowed to run.  Nobody lost their way because there was a fence to guide them.  The winner was considered by is parents to be the least athletic member of their family.  Well done! Guess who?  To the adults the challenge was both mental and physical, we tried to learn about the vegetation and we had a difficult walk.  After lunch we began the long descent in our comfortable downhill footwear, we dodged rocks and cautiously negotiated scree so as not to glide down the Dyke.  Amongst the stones there were flat cakes of ferricrete, which might be of interest to a budding geologist.

Two paddock fences were encountered, Lone Cow Estate is a veritable “plateau de mille vaches” and beaucoup de heifers and steers which bravely climb every mountain, so long as it is not more than 500 feet from water.  They thrive on palatable grass.  Soil so rich in minerals has never caused grass poisoning.  Fire breaks ensure that the cattle do not become roast beef to soon.

Some botanists seem to think that the fires on the Dyke maintain the existing balance of ground cover and trees.  If the annual veld fires ceased would the vegetation respond.  Where short grass predominates, the burn is the most severe and prevents soil formation, as no decayed material accumulates.  Furthermore, the mountains catch the storms and prevailing winds so that the humus is unlikely to remain in situ except in fissures.  Absence of soil accounts for the thin cover o stunted trees especially on the northern and eastern aspects.  This fact influences the choice of a route for the Raphia palms visit.  After seeing the palms we should turn back through the wide fault called the Gurungwe Gap to the west side where the vegetation is more interesting so that comparisons can be made.

With the help of Trevor Gordon we were able to identify over 60 tree and shrub species.  Just in revision we will all remember three open hillside species.  Aloe ortholopha which we saw on the island at Mutorashanga crossroads.  The dyke raisin bush, Ozoroa longepetiolata with its “corned beef” slash.  These two species are endemic to the dyke (until someone finds them elsewhere).  The bunched sickle shaped leaves are characteristic of Protea petiolaris where the leafstalks and flowers are tinged with pink.  Four other proteas occur on the dyke.

We found two exciting riverine trees beneath the water berries, Syzygium cordatum, on our second morning stop.  The first was Maesa lanceolata with long, wide, serrated leaves and a ‘rain forest’ look about it.  We saw it again in the late afternoon and smelt its pale coloured clusters of flowers.  We were sorry we did not see more flowers or fruits on the other trees as they do help to fix the names in the memory.  Secondly, the Latin mouthful, Rapanea melanophloes, with bluish green waxy leaves which have purple leafstalks.  Both Maesa and Rapanea have finely gland-dotted foliage.

Ian Barron studiously noted the ‘running boards’ along the leaves of Schrebera alata which grew beside the rocky path down the kloof.  A cluster of wooden pears was gathered for the collection.  Lastly we all, and particularly Gill Henderson remember Faurea speciosa with its rough bark, beautiful red leaves for winter flower arrangements and fruits which resemble large, grey woolly caterpillars.

At one place in the kloof dark moist rocks and evergreen trees towered above us, it was a rain forest in miniature, a hallowed spot with ferns, stem fruit, Bequaertiodenron magalismontanum, Carissa edulis, Apodytes dimidiate and Ilex mitis, African holly.  We lingered here to absorb the serenity.  It was mixed feelings that we moved on to where the vehicles awaited us.

There was so much that was different from home so this Tree Day ‘up the airy mountain and down the rushy glen’ was really appreciated, a well chosen venue suggested my Mary Malan.  We had tea and rested in the garden at Elaine and Ian Fraser Mackenzie’s home, thank you both and big brother Peter FM for your hospitality and for arranging the programme.

Finally, a very special thank you to Trevor Gordon for coming to join us and make the day because he introduced us to the geology and the plant communities of party of the Great Dyke.  We were very touched by what he told us at the end of the day, that it as his first time out looking at trees since his illness.  We were very honoured and hope that he did not overdo things.  It was a long day, perhaps too ambitious, so much new to us.  Thanks to everyone who attended.  The Ayrshire Branch members were grateful to Ian Barron for checking up on the safe arrival at their respective destinations.

 

MATABELELAND BRANCH

Sunday July 3rd :   Matopos, to a kopje a short distance along the Fort Usher Road.  Meet at Dora Webb’s house, 6 Caithness Road, Hillside at 0830 hours where there is safe parking for cars.  Alternate meeting point, Retreat at 0840 hours.

Sunday August 7th : Mubukuweni at 0830 hours.

JUNE OUTING :  For our June outing we went to the Kalahari sand area which borders on the Municipal Farm at Aisleby/Good Hope.  Much of the natural vegetation has been cut out in the past to make way for agriculture, but enough remains to be of interest.

Baikiaea plurijuga were plentiful, from young saplings to very old trees.  There were some fine specimens of Pterocrpus angolensis, seeding profusely, which have escaped the ravages of the disease which has struck so many of this species in the Gwaai area.  We spent some time sorting out the Combretum species and eventually decided on Combretum collinum, C.psidioides and C. zeyheri.  Three species of Grewia were present, G.flavescens, G.monticola and G.retinervis, as well as two species of Ochna, namely O.pulchra and O.schweinfurthiana.  There was a Strychnos pungeus with its very sharp pointed leaves, and we identified Acacia fleckii with it peeling  bark.  On our return journey we stopped to look at a Boscia albitrunca which for some reason had been spared and was a long tree in a vast area.

-D.Webb

 

PAUL COATES PALGRAVE – SOME MEMORIES

It was with much regret that members of the Society heard of the sudden death of Paul Coates Palgrave on the 6th June.  Those of us who knew him will recall his tireless interest in trees and in so many other nature related topics, interests shared by his wife, Meg.  Reminiscing about Paul with Meg, at their home, ‘Craighall’ outside Harare, we were amazed at the energy and enthusiasm for learning which have been the basis of Paul’s life.

Born in Harare on 18th August 1929 Paul was the youngest of his family.  He was educated in Harare, completing his secondary education at Prince Edward School, from where he went dairy farming before settling on his future career in the field of medical technology.  Meg told us, however, that Paul’s over riding passion was always his photography.  Over the years he acquired a number of cameras and a mass of related equipment, much of it designed and made by himself.  At one time he even made his own slide projector.

His interest in trees was no doubt sparked by his mother, Olive, who was a most talented artist.  Although not a botanist in te formal sense, she produced the beautiful and accurate paintings of leaves, fruits and flowers which were used to illustrate “Trees of Central Africa” published in 1956.  Now considered a collector’s piece, this publication was a family affair; Paul did most of the photography, and is brother Keith wrote the text.

Although his art was generally that of creating images on film, Paul also inherited some talent from his mother, and over the years produced works in varying media, from paintings of scenery and birds and illustrations for newsletters, to a superb paint and mirror wildlife work which hangs in his home.  Meg described how they had actually made and poured the mirror, following a formula and directions in a book.

Meg and Paul were married in 1957 on London Farm, Juliasdale, the home of Meg’s parents.  Thus began a 25 year partnership of study, research and frequent camping trips to wild places in Zimbabwe.

Paul worked in Harare for 15 months after his marriage and then applied for a post in Mutare.  Accommodation was at that time desperately short in Mutare, and they stayed initially in the old Toronto Mine house, near the Penhalonga road.  It was there that Meg and Paul were introduced to the fascination of bird watching by an elderly neighbor who lent them a copy of ‘Roberts’.  The stage was set for a new photographic subject and in no time Paul was inventing devices to make bird photography possible on a shoe string, so to speak.  Meg recalls the setting u of a birdbath and the agonies of trying to induce birds to land on a particular twig so that the camera, concealed in the bushes and set off from a distance, would capture the subject.

Later they moved to a house close to town set on half an acre.  Meg recalls their excitement at finding Fagaropsis angolensis in the garden.  Here began 12 busy years for Paul and Meg, both at work and at home.  Paul was always on call, and made trips at weekends to the lab. To check cultures and do emergency tests.  However  the lab. was close enough to the house for him to rush home at lunch times and after work to work at his many interests.  It was here that Meg and Paul became fascinated with butterflies and moths, particularly with discovering which caterpillar gave rise to which adult.  They began work on a film on the topic and the house became a vast container for endless jars of muching caterpillars.  After numerous disasters and modifications of techniques and equipment, the film was at last run off on 8mm film, but later entirely re-filmed on 16mm.  During this time Paul would sometimes wait at work like an expectant father for the emergency call from home to tell him that the moth egg Meg had been watching for days was about to hatch.  Then would follow a frantic rush to capture on film the priceless moment of emergence of a minute caterpillar whose life history would complete itself in a jar on the dining room table.  During this time too, the two children, Shirley and Tony were born, in 1959 and 1962 respectively.  Such was their environment that Paul’s delicately set up photographic sets were inside the playpens to keep the children out!!

The Mutare years saw much activity in other fields.  Paul joined the Museum Society and was Chairman for several terms.  He and Meg were involved in organizing meetings and talks and Paul edited the newsletter, often contributing his sketches for articles.  He started and organized the camera club.

He also developed an interest in stone polishing and tumbling and built his own grindstone and buffs.  He enjoyed woodwork, particularly working on the lathe.  But photography was ever the most important, and he now branched out, under the guidance of Don Broadley, to include frogs and reptiles in his repertoire.

Paul began photographing snakes for the subsequent book “Snakes of Rhodesia” published in 1975.  There were some anxious moments caused by these photographic subjects.  On one occasion Paul was set up to photograph a live green mamba on the dining room table, when there was a power cut.  Many panic stricken minutes of searching for matches, candles and torches followed.  When enough light was finally produced to hunt for the errant snake, it was discovered that it was in the same position on the table, apparently asleep!

Paul began recording bird and animal calls in 1963 during a trip to the Umfuli and Umniati rivers.  The first recordings were made using a headlamp fixture from a V.W. as a reflector.

The family returned to Harare in 1971 where Paul was promoted to Chief Technologist at the Public Health Laboratory; a position he held for 8 years.  During this time he saw the move to the Andrew Fleming (now Parirenyatwa) Hospital, and was involved in planning the new laboratories.

Work had now started on several more books “Common Trees of the Highveld” by Bob Drummond and Keith Coates Palgrave was published in 1973.  Paul and his brother Deric took all the photographs.  Some of Olive Coates Palgrave’s paintings were also used in this book.  Paul was also invited to do the plates for “Butterflies of Rhodesia” Bundu Series by Richard Cooper also published in 1973.

But for Paul undoubtedly the main work of the 1971 – 1976 period was the photography and related work for our Tree Bible, “Trees of Southern Africa”.  He and Meg worked long hours at laying out and photographing the leaves for the book, and travelled widely, photographing fruit, leaves and flowers for the colour plates.  It was an exciting and exhausting time, and would no doubt make a story in itself.  Paul and Meg did much of the research as to the common names, and Paul and his daughter and son drew most of the fruits.

Finally, with the book published in 1977, the enormous research, photographic and artistic proof reading, correction and layout work complete Paul and Meg began devoting more time to the Tree Society which they had joined in 1971.  Since then they have been among our most active members.  Those of us who go on the bus will know the extent of effort which has gone into making our trips the pleasure they have been.  During Meg’s two terms as Chairman, Paul was undoubtedly an able “Chair’s leg” accompanying her on reccies and collecting lists of species we would see.  More sedentary members of the Society will remember the writings of the Coates Palgraves in “Tree Life” drawing on Paul’s experience with producing interesting newsletters.

They also wrote jointly for “Science News” giving interesting accounts of our trips.

On the committee Paul acted as minutes secretary, summarizing our sometimes verbose meetings accurately and punctually.

As a final illustration of his varied talents, Meg showed us a photograph of their daughter’s wedding cake, entirely iced by Paul himself.  He must have occupies himself for endless hours designing and executing the perfect flowers and edging of which a professional confectioner would have been proud.

So many of us in the Society knew Paul, for he and Meg traveled widely meeting members of the Ayrshire and Matabeleland and branches and we will have different memories.  To some it will be of him wandering through the bush with his straw hat, festooned with books and cameras.  Others will remember him endlessly stoking fires and brewing gallons of tea at Binga Swamp to keep us all fuelled for pulling the thorn.  Many too will remember the hospitality we have had at ‘Craighall’ during a Tree Society AGM and various other occasions, where we have toured the property to see the many beautiful trees which were planted.  Those who peruse the herbarium will come across many specimens of Paul’s, meticulously pressed (Meg tells us the fine press was achieved by the Coates Palgrave technique of placing the specimens under the caravan mattress).

Whatever Paul was to each of us, we would wish to pay tribute to a husband, father, colleague and friend who is sadly missed and acknowledge the ways in which he has enriched the lives of those about him.

-C.Haxen

 

ROOT NOTES  On our May weeding trip to Binga Swamp Forest certain Tree Society Committee members (no names please) very excitedly pulled out half a dozen 1 m high “Toona ciliate” (=cedrela) trees.  While happily filling our faces at luch time and discussing the one and only Ekebergia capensis specimen known from Binga, we glanced over the general direction of our gloating weed pile to notice the odd leaflet on the end of our ‘cedrelas’.  It was with progressively sinking hearts that we wracked our brains trying to decide on the paripinnate, even leaflet, or imparipinnate, odd leaflet, status of Toons and Ekebergia.  A few hours later with “Trees of Southern Africa” in our hands we saw the worst Toona ends in an even pair or leaflets and Ekebergia in an odd terminal leaflet!  Depression and retribution! Then the fatal moment of bumping into Dick Petheram in the herbarium with the wilted imparipinnate specimen for identification – quick apology and exit of one committee member.

A reluctantly answered phone call later and there it was – despite all the books said, the experts had agreed on Toona!!  An intensive search around the local trees confirmed the diagnosis, young Toona ciliate are decidedly odd leaved and only became even leaved later.  A quiet celebration and well learned lesson for us all.

KimST.J.D.

MORE ROOT NOTES  Everyone seems to understand basic zoology.  If asked to arrange a frog in the progression jellyfish, shark, lizard, bird, they will put the frog between the shark and the lizard.  But if asked to put the BIGNONIACEAE, jacaranda family, into the sequence STRELITZIACEAE, strelitzia family, CAESALPINIOIDEAE, Cassia family, RUBIACEAE, gardenia family, they fall apart as if there were being asked to translate ancient Arabic.  And yet it is not very difficult, certainly not beyond any of us, if we know three easy rules:

All parallel veined leaves (e.g. strelitzia) are conventionally placed before net veined leaves (e.g. cassia, gardenia and jacaranda).

Net veined leaves with separate petals (think of a cassia flower) are placed before fused petals (visualize a tube like gardenia and jacaranda).

Fruit that sits below the flower (remember a gardenia where the remains of the floer remains on the end of the ripening fruit) is considered a more advanced feature that fruit that develops within the petals (as in a jacaranda).  So on this basis the BIGNONIACEAE (jacaranda family) falls between the CAESALPINIOIDEAE, Cassia and a RUBACEAE, Gardenia.  One Eventually gets to know where to find the Biblical books by their ‘almost’ chronological sequence, yet as we are always consulting books like “Trees of Southern Africa”, Coates Palgrave, it will help us a lot to get a basic idea of how things are arranged, it will also open up the arrangements in most of our Southern Africa herbaria which follows the arrangement of the botanists Engler and Prantl.  This is not a real classification and does have a couple of flaws.

-Kim St.J. Damstra

 

 

Mussaenda arcuata flowering; Photo: Bart Wursten. Source: Flora of ZimbabweVangueria apiculata. Photo: Bart Wursten. Source: Flora of Zimbabwe