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Tuatara: Volume 2, Issue 1, March 1949

The Conversion of Rain Forest to Grassland in New Zealand

page 37

The Conversion of Rain Forest to Grassland in New Zealand.

New Zealand has, in round figures, 18,000,000 acres of sown grassland, of which 12,000,000 acres have replaced forest, 4,000,000 acres have replaced tussock, and 2,000,000 acres have replaced fern and scrub.

Of the area of forest felled and sown to grass some 10,000,000 acres have been more or less successfully converted to grassland, the remaining 2,000,000 acres reverting to secondary growth. Some 2,000,000 acres are still in natural fern and scrub and some 3,000,000 acres of standing forest await development or are on country too steep to develop.

The total grain, green fodder and root crops occupy approximately 1,000,000 acres with plantations, orchards, market gardens, private grounds and fallow a further 1,000,000 acres making in all some 20,000,000 acres effectively occupied and farmed. To this must be added some 14,000,000 acres of Montane tussock country which is range grazed in large holdings.

The original forests may be classified into two main ecological types: (1) Rain forest, (2) Subantarctic Beech forest. In the latter southern beech (Nothofagus) is dominant. The rain forest is divisible into associations in which either broad-leaved trees or coniferous trees (Podocarps) predominate. Many such associations are developmental; tawa (Beilschmiedia Tawa) would appear the climax dominant in rain forest, while rimu (Dacrydium cupressinum), rata (Metrosideros robusta), Matai (Podocarpus spicatus), miro (P. ferrugineus), totara (P. totara), hinau (Elaeocarpus dentatus), rewa rewa (Knightia exelsa) and kamahi (Weinmannia racemosa) are sub-climax dominants. In the north the kauri (Agathis australis) forms an unstable climax, this dominant being migratory in character. Tarairi (Beilschmiedia Tarairi), tawhero (Weinmannia sylvicola), puriri (Vitex lucens), nikau palm (Rhopalostylis sapida), and tanekaha (Phyllocladus trichomanoides) occur as sub-climaxes. Tree ferns, mamuku (Cyathea medullaris), wheki (Dicksonia squarrosa), silver fern (Cyathea dealbata) are common in developing rain forests.

Tussock grassland, bracken fern (Pteridium), heath and scrub associations precede forest. Of these associations, the following genera characterize the development in ascending order from bare ground page 38 to forest tree establishment: Raoulia, Festuca tussock, Poa tussock, Discaria, Danthonia tussock, Carmichaelia, Muehlenbeckia, Pimelea, Dracophillum, Styphelia, Pteridium (stunted), Pomaderris, Olearia, Cassinia, Leptospermum, Pteridium (strong), Coriaria, Hebe, Griselinia, Coprosma, Brachyglottis, Rapanea, Pseudopanax, Pittosporum, Myrtus, Nothopanax, Dicksonia, Cyathea, Schefflera, Fuchsia, Edwardsia, Pennantia, Melicytus, Aristotelia, Hoheria. In the swamps Typha, Phormium and Cordyline usually precede the podocarps, Dacrydium Colensoi, D. intermedium and Podocarpus dacrydioides. In nature, complete climax dominance seldom occurs, owing to disruptive factors such as fire, earthquake, volcanic action, land-slides and gales breaking the forest cover, whence an initial surface for forest development occurs. Indigenous induced and exotic induced associations are common in New Zealand.

Felling the Forest, Burning and Sowing.

The forests are felled by axe during the winter and early spring on a contract system, the men feeding themselves and housing themselves in a tent or whare. The price of felling average forest, leaving all trees above 30 inches in diameter standing, was approximately $2 per acre. The cost of felling today would be $4 to $5 per acre. Under-scrubbing precedes the felling of the larger timber; the success of the burn depends upon the thoroughness with which this operation is carried out. Next, the forest trees up to approximately 30 inches in diameter are felled by a system of driving, the trees being notched on the upper and lower side of the drive, which is commenced at the top of the slope downwards. A good drive lessens considerably the cost and toil of felling. In very wet climates the bigger trees are left standing on the supposition that these occupy less space standing upright than if they are felled.

In a normal season, early in January, the owner anxiously watches the weather conditions and, given a dry spell of approximately two weeks, makes preparations for the burn. If distant from the homestead, he and his team may camp on the spot to await a favourable steady wind, blowing away from the uncut forest. Successful grassing of the country depends upon the success of the burn, more particularly in areas of high rainfall. A steady, hot fire if possible is desired to burn all fallen timber, leaf mould, seeds and fern spores lying dormant on the forest floor. A white ash, called a white burn, is the objective: a black burn results from a skimming fire where the heat is not sufficiently intense to burn the timber, leaf mould, seeds and spores on the forest floor.

Given a favourable wind the fire is lighted on as long a face as possible and happy is the man who sees a solid wall of fire sweeping page 39 across his felling. A poor burn may mean ruination or a considerable setback in the development of his block.

After the burn a telegram confirms the order for seed which may be already on hand, particularly if the season is late. When the burn is made in early summer a sowing only of soft turnips may be made, the grass seed being sown later among the turnips or when these are being fed off in the autumn. A good crop of turnips will in large measure pay the cost of felling the forest and grassing the burn. From grassing trials with and without soft turnips on a primary burn, there would appear to be no detriment to the final sward through including the turnips in the mixture, or in making a sowing of turnips prior to the grass seed.

The seed is taken to the burn and distributed at convenient spots, working across the slope and from the top downwards. The seeding is made broadcast by hand, one sower following another at a cast distance further down the slope. The seed is carried in a sowing bag on the shoulders and across the back and is so slung that the seed falls to the right and left side of the bag in which openings are made convenient to the hands. On easy country both hands are used for sowing, but on steep country one hand is usually fully engaged clinging to stumps or logs while the free hand sows.

The seeds mixture varies considerably and is dependent in large measure on the class of forest felled and on rainfall. After some considerable experimentation on primary forest burns in the belt with 50 inches and over of rainfall, the following seeds mixture has been devised:

lb. per acre
Certified Perennial ryegrass 12
Certified Perennial Short rotation ryegrass 8
Certified Cocksfoot 6
Certified Crested dogstatil 3
Certified Brown top 1.5
Certified Danthonia pilosa 3
Certified Mother seed white clover 2
Certified Lotus major 1
Certified Soft turnips or rape 0.5
Total per acre 37 lbs.

Burns may be differentially sown. The spurs, ridges and poorer aspects being sown with one seeds mixture, the better flats and easier slopes with another. In the former case Brown top (Agrostis tenuis) may be increased to 2-3 lb. per acre and Chewing's fescue (Festuca rubra var. fallax) 3 lb. added, whereas on the fertile areas these grasses together with Danthonia pilosa, may be eliminated or considerably page 40 reduced and such grasses as timothy (Phleum pratense), alsike (Trifolium hybridum), and red clover (Trifolium pratense) added.

The cost of seeding a primary burn was from thirty to thirty-five shillings per acre but present day costs are between $3 and $4 per acre.

Fencing, Tracking and Stocking the Burn

As soon as possible after sowing, the burn is ring-fenced and later subdivided. Fencing is a considerable item and is expensive, particularly where heavy timber has to be cleared from the fence line and where much shelving has to be done on steep, arete ridges. Fences are erected along the main ridges and down leading spurs, and erection across slopes studiously avoided for fear of slips. Wherever possible sunny country is fenced off from shady country to facilitate control of stocking. Fencing is usually done on a contract basis. Totara posts are used for the most part. A fence consists of four posts to the chain, seven plain galvanized No. 8 wires with three or four battens betwen each post. The cost of such a fence, including erection, was approximately $2 per chain, but today costs are up to $6 a chain for material and erection.

Stocking the new burn takes place about eight weeks after sowing, both sheep and cattle being employed. In areas where much timber remains unburnt, tracking of the burn to enable stock freely to graze all parts of the burn is necessary, for the ability of stock to graze and tread the burn in large measure predetermines whether the succession is to grass or back to forest. The proportion of sheep to cattle varies according to the nature of feed and class of country. One cattle beasts to 5-7 sheep is necessary wherever the danger of secondary growth is real. Where the country is comparatively easy to hold, one cattle beast to 10-15 sheep is a fairly reliable figure as practised, but the number of cattle to sheep could with advantage be increased.

Ecologically, the stock factor in subsequent developments is of paramount importance. The sown grasses in themselves are powerless against the myriads of seedlings and sporelings of shrubs and ferns that arise once the forest shade is removed. It is a struggle often for many years against these growths, and success or failure of the grassland sward depends on the number of stock that are maintained on the area to eat off and tread out fern and scrub growth and thus to maintain the ecological balance in favour of grass rather than forest. Stock, secondary fires, the slash-hook or grubber are all ecological agents that work towards this end.

Of the deforested country in New Zealand today, some 2,000,000 acres have carried insufficient stock to maintain the grass versus forest balance and regeneration back to forest is proceeding apace.

page 41

The class of stock and stock manipulation may entirely alter the ecological conditions both for the early precursors of forest and for grass. There may arise induced associations entirely different from the sown grass sward and from the association of fern and secondary forest trees that would arise if these were unchecked by stock after the primary burn. Thus, under a system of close and continuous grazing by sheep we may see either a swing over to hardy, low-producing, light-loving grasses or to unpalatable fern, scrub and weedy growths according to the ecological conditions set up. If these latter growths predominate, all stock will ultimately be forced off the area and succession to secondary forest and ultimately to primary forest proceeds.

The most common stock-induced associations on the deforested areas are (1) manuka (Leptospermum scoparium), hard fern (Paesia scaberula) and piripiri (Acaena novae-zelandiae). Of the grass associations, Danthonia pilosa may be regarded as an indigenous-induced association and Agrostis tenuis as an exotic-induced association. The former is found on poorer and drier country and the latter on the more shady and wetter country.

The grass swards on deforested hill country vary considerably in botanical composition, depending on the fertility of the soil (whether natural or induced artificially), by the class of stock, and the method of stocking. In the best swards, perennial ryegrass (Lolium perenne), cocksfoot (Dactylis glomerata), crested dogstail (Cynosurus cristatus), and white clover (Trifolium repens) are dominant. These have a carrying capacity of three to six ewes per acre throughout the year. Some phosphate topdressing on the best of these is practised. Second class swards contain a certain amount of the foregoing species with more or less browntop (Agrostis tenuis), Danthonia pilosa, Yorkshire fog (Holcuta lanatus), sweet vernal (Anthoxanthum odoratum), Lotis major, suckling clover (Trifolium dubium) and flat weeds. Such swards carry one to three mixed wet and dry sheep per acre in addition to the cattle. The poorer and drier country carries a Danthonia pilosa dominant sward, with the following species subdominant: sweet vernal (Anthoxanthum odoratum), hairgrass (Festuca myurus), ratstail (Sporobolus indicus), New Zealand ricegrass (Microlaena stipoides), suckling clover (Trifolium dubium), clustered clover (T. glomeratum), striated clover (T. striatum), and hare's foot trefoil (T. arvense). Subterranean clover (T. subterraneum) in more recent years is playing an important role in such areas where topdressing with phosphate is being practised.

Control of Secondary Growth

The control of secondary growth is a feature of almost all deforested hill country. The process consists in firing the growth while page 42 standing or after felling, and reseeding to hardy and persistent grasses and clovers. Cattle are regularly employed to deal with Pteridium by crushing, but a comprehensive series of experiments on the regrassing of run-back country by the writer, show that the firestick followed by the seed bag prior to good stock manipulation are more effective in re-grassing operations than mere crushing by cattle. Nonetheless, the exponents of the crushing method have many millions of acres to their credit. Removal of logs and standing stumps by logging-up and burning eliminate establishment areas for fern and other growths and facilitate grazing and treading by cattle.

The seeds mixtures in these secondary scrub, fern or logging-up burns are important. Much deforested hill country went repeatedly back to secondary growth until suitable seed mixtures were devised from carefully conducted experiments. The introduction of Browntop (Agrostis tenuis) and Lotus major to wet hill country has in many instances turned failure to success. The following seeds mixture has been found the most suitable for virtually all the wetter secondary hill country:

lb. per acre
Certified Perennial ryegrass 12
Certified Crested dogstail 4
Certified Brown top 2
Certified Danthonia pilosa 3
Certified Lotus major 1
Certified Mother Seed white clover 2
Total per acre 24 lbs.

In the Auckland Province 2 lb. per acre of Paspalum dilatatum may me added with advantage. On the drier areas of the East Coast, the Lotus major may be eliminated and 2 lb. per acre of subterranean clover (Trifolium subterraneum) added. The cost of this secondary burn seed mixture is today approximately $2 per acre. Felling the scrub, if at all dense, prior to burning will also add approximately $2–$3 per acre to the cost of re-grassing.

Maintenance Costs and Pre-disposing Factors to Success or Failure in Farming Hill Country.

It can be fairly safely reckoned that a settler succeeds or fails according to the maintenance costs of his country and whether he has ready cash to meet those maintenance costs as they arise. The burn must be well grassed and well fenced, and cattle must be acquired even though the direct profits from these are often exceedingly low. To stock deforested hill country entirely with sheep leads to disaster. Much of the poorer hill country reverts to manuka (Leptospermum scoparium) which must be either pulled or cut. Neglect leads to an page 43 almost pure association of this scrub in some 5-10 years with an elimination of the grassland. The same is true of other scrub growths such as gorse (Ulex europeaus), blackberry (Rubus fruticosus), cotton-wood (Cassinia leptophylla), etc. Piripiri (Acaena sanguisorbae and A. novae-zelandiae) without cattle thrives exceedingly, particularly under close grazing by sheep. Pteridium without the use of cattle assumes control, particularly on the more difficult country. The erection and maintenance of fences presents a costly burden, particularly in country where slips are bad. Losses in cattle through falls over cliffs and into ravines are often severe and tutu (Coriaria) poisoning takes a considerable toll. Distance from markets and cost of transport to and from the farm must be considered. The land rent is not unduly high, as the unimproved value of much back-country varys from five shillings to $2 per acre. The cheap rent of such hill country has lured many an impecunious settler to take up this type of country only to be beaten through lack of funds to meet maintenance costs and to walk off after many years' toil. Settlers of equal ability have gone into various classes of bush country. Those in a certain area will make good and the others will fail, largely because in the one class of country the maintenance costs are low and in the other high. Nonetheless over and above all topographical, climatic and soil variations is the undeniable fact that some farmers have the innate genius—some of my critics call it “guts”—to work themselves, direct labour, and to utilise stock and through them to win the hill country to grass. In the midst of a wilderness their country is clean; their fence lines proclaim their farm boundaries from miles distant; their worries are over as far as forest regeneration is concerned, and the ecological balance is well set towards grassland.

Finance, labour, topdressing, overseeding, fencing, the intelligent use of fences; the appropriate class of stock and the grazing management of that stock, i.e., rotational mob grazing, rather than sparse, set stocking—together with the will to win of the farmer, and often of the farmer's wife, are fundamental to the success of forest conversion to grass.

Management of Hill Country Grasslands

The grazing management is extremely important and without exception sheep and cattle are employed. In certain districts gorse and blackberry are prevalent and goats may also be used. The cattle are really the hill country implement for consolidation and crushing out undesirable secondary growth and to act as the mower to clean up roughage in the autumn and winter to give young and succulent growth for the ewe and lamb in the spring and for the hoggets in the winter. Set stocking with sheep and cattle may be practised, but a system of rotational grazing where it can be adopted is definitely page 44 holding the country better than under set stocking, particularly where there is a tendency to overstock. Spelling to allow the growth which will create shade at the ground surface vastly encourages the better grasses and allows these to make better growth than would be the case under continuous set stocking. Spelling for a whole growing season is often resorted to; the spelled area becomes the wintering paddock for cattle which are removed prior to spring when the growth that follows is excellent for ewes and lamb. This periodical spell is of considerable value to hill country pastures. Soil fertility is actually increased as a result of the increased plant growth and its subsequent return in humus and stock residues. Trailing and mat-forming weed growths are lifted off the ground or smothered out, and light-loving, low-producing grasses are discouraged. Adequate fencing is a prerequisite to rotational grazing, but the paddocks need not be unduly small as watering in small paddocks on hill country is often a serious problem.

Summing up, the really successful man of the hill country is the cattle man and the cattle-sheep man where the grazing is of the rotate, mob-graze type. The cattle to sheep ratio is held important and this varies from 1 to 4 or 5 up to 1 to 10 or even lighter. The actual ratio is probably less important than the grazing management. Set stock, whatever the ratio, is less likely to succeed than rotate mob grazing be it either with all cattle or all sheep or with a high or low cattle to sheep ratio.

The despoilers of the hills is the hard set sheep grazier and the man who attempts to dairy on the small limited flats and easy foothills adjacent to or subtending the hill country itself. The indifferent absentee holder and speculator are a menace to the hills: so too are the unoccupied Crown Lands and much Maori held land. A vigorous occupancy is the keynote and it behoves the State to encourage occupancy with provision of all-weather access roads, with schools and social amenities to help and inspire youth to put his or her heart into the work and into the hill country. The hill country is and always will be a young man's country and deterioration must set in anew following on old age. Adequacy of reward for the hills is essential to enable old age to retire from the hills once failing strength is no longer competent for the task of farming that country.

The surge of secondary growth coincides with periods of depressed prices for farm produce and with labour scarcity such as in time of war. The World War I took many hill country men as did also World War II, and although the latter has been over for 3 years the return of young men to the hills is lamentably slow owing largely to more remunerative jobs offering in built up areas of population, together with the disinclination of the State to foster rehabilitation of difficult page 45 farming country by returned soldiers. The army and air force still claim large numbers of the prime of the country's youth.

Certain of the more isolated secondary growth areas may yet have to wait a further generation of young men before the surge forward into this class of country is undertaken. In the meantime secondary growth will dominate and what grassland has survived will be obliterated by such growth, until new blood takes the country up again with renewed vigour. Within these deteriorated areas there is, however, a tendency for much country to be farmed with the firestick to open up periodically the secondary growth sufficiently to allow some stocking of the area and while there is some merit in this type of farming its unsystematic approach will never win the country to grass although each burn sets back the forest regenerative processes and allows some light into the sward to encourage its development.

Stumping, Ploughing and Resowing Deforested Country

It is impossible to say with accuracy the acreage of deforested country in New Zealand that has been stumped, ploughed, and resown, but the area now is considerable and is increasing each year.

After the forest has been felled, secondary scrub and logging-up burns proceed until only standing stumps remain. These are ultimately removed by burning out, by haulage or by blasting, operations which are usually postponed for upwards of 20 years after the burn, by which time decay has set in and removal is comparatively easy. Of recent years the bulldozer has ben successfully employed in clearing, stumping and logging up deforested country. Secondary log fires may be on a grand scale and the speed with which fire spreads in a dry season among the fallen and standing timber is amazing. Fanned by a strong wind, log fires may spread over thousands of acres in a few hours and the writer has experience of such a fire so darkening the sky that artificial light had to be used well into the morning over 100 miles distant from the scene of the fire. Such a fire has dreaded consequences within the immediate area concerned, and stock, hay stacks, outbuildings and homesteads usually suffer. However, incalculable good is done in so far as clearing the country of much rubbish is concerned.

Ploughable Hill Lands

A great deal of hill country, even when cleared of logs and stumps, is unploughable, but one of the outstanding features of development of hill country is the steepness of much of the country that is being turned over by the plough. This is possible by the strategic use of ploughing on the contours and by the use of hillside ploughs and page 46 giant discs. With some technical improvements in hillside implements this ploughing of hillsides would proceed apace. It is a practice highly to be recommended. There is nothing like the plough to get rid of weak weedy pastures, or to destroy, almost for all time, all manner of secondary growth. The plough buries everything and enables us to introduce effectively a better quality sward, a denser sward, a higher carrying-capacity sward and one that pays more handsomely to manure than do the weak, weedy swards that characterise much of the country, particularly where poor class seed mixtures were used in the original bush burn sowings.

Ploughing, or giant discing the hills wherever possible, is again, an individual-farmer characteristic. One man will plough where another will claim it is utterly impracticable to plough, just as one will topdress with seed and manure where others claim topdressing is out of the question; one will use and work cattle where another will say cattle losses are too great: one will pull or cut manuka and other scrub, will burn and sow at every available opportunity while the other will be dilitant and lose golden opportunities to clear the country: one will erect fences and will use those fences to the full in controlled rotate-mob-grazing, another will try to do without fences and will not use intelligently the fences he has. Such individual characteristics make or break the more difficult hill country.

The seed mixtures for these hillside sowings are important. May be the area will never be ploughed again in the lifetime of the present owner and failure to get a good sward at this time will mar the whole future of that country. Here, as in all grassland development, success or failure rests on the number of animals that can be maintained and adequately fed on the established sward. This ploughed hill land, properly sown and given a good start with ample and even liberal manuring during their early establishment phases, will carry four or five sheep per acre, plus some cattle, and this carrying capacity, where it can be maintained, will just simply make the country and will keep the sward growing for all time with a normal yearly or two-yearly application of phosphate to keep the clovers going strongly.

Ploughing hillsides not only destroys weeds and secondary growth, but it definitely tends to level the country and to eliminate innumerable hillocks and small hollows that can never produce as well as the more even sward. Whereas now the hillocks are carrying mainly moss, poor type grasses and flat weeds (largely because these hillocks never get trodden upon or urinated upon by stock) the levelling off of these and the filling of hollows institutes a uniform growing condition and gives a greater chance for stock to tread over and urinate upon the sward.

page 47

This is true not only of the hills but also of the flat and undulating country. Ploughing enables the country to be levelled and advantage should be taken of every period when the plough goes in to level that country as much as possible to bear on the job during the cultivation, even to bringing in bulldozers or road-graders. Every flat or undulating farm taken out of forest should be equipped with a good levelling board.

Nonetheless on the hills stock will tend to track and contour the hillsides and the ultimate fate of well stocked country will be a series of broad or narrow terraces with steep slopes between upon which stock seldom tread. From a soil conservation point of view maybe this stock-terracing could be expedited and guided by the running of coun our furrows along the hillsides, but however the terracing is done, there will tend to arise two fairly distinct ecological associations on the hills—one, dominated by grasses where the stock tread and urinate, and one on the steep slopes betwen the terraces dominated by clovers and lower-fertility demanding grasses. The more stock we can carry the broader and more numerous will these terraces become. There will also be a considerable expansion in the size and area of stock camps, which too, will be dominated by the better grasses and clovers just so long as those camps are not too closely confined to small ridges, lone trees, etc., where too great a concentration of treading leads to bare ground in the summer and to annual weeds in the winter and spring. The avoidance of these over-used camps by a grazing management designed to rotate the stock more and possibly by the strategic space planting of many more trees in any one paddock is one of the problems of the hills. Perhaps it is permissible too, to speculate upon the ultimate relationship of the terraces and camps to the steep slopes between the terraces. These steep slopes, if more liberally fertilised with phosphate than the terraces and camps can be made to grow clover in abundance. That feed, when consumed, supplies from the dung and urine of the animal the all essential nitrogen to keep the grasses of the terraces, camps and uniformly grazed slopes up to high productivity and hence to raise the carrying capacity of the country as a whole.

Of recent years on the more level deforested country, stumping and ploughing, and much reploughing, has been expedited by the use of bulldozers and by the introduction of certified strains of grass and clover seeds and by a fuller realization of the values of artificial manures, particularly when used on a sward constituted of herbage strains that are capable of giving high returns. The following seeds mixtures have more recently been devised and are recommended on a ploughed and prepared seed bed:

page 48

Perennial Pasture

lbs. per acre
Certified perennial ryegrass 20
Certified short rotation ryegrass 10
Certified cocksfoot 5
Certified Crested dogstail 3
Certified Timothy 3
Certified White clover 3
Certified Mont. red clover 3
Total per acre 47 lbs.

Short Rotation 3-4 year Pasture

Certified short rotation ryegrass 25
Certified perennial ryegrass 10
Certified Mont. red clover 3
Certified N.Z. cowgrass 3
Certified White clover 3
Total per acre 44 lbs.

Temporary Pasture 2 years

Certified short rotation ryegrass 20
Certified Italian ryegrass 20
Certified N.Z. cowgrass 6
Total per acre 46 lbs.

For the ploughed steeper slopes some of the more sward-binding grasses are advised and the following mixture is recommended:

Certified perennial ryegrass 20
Certified short rotation ryegrass 8
Certified Cocksfoot 6
Certified Crested dogstail 3
Certified Browntop 1
Certified White clover 2
Certified Lotus major ½
Certified Mont. red clover 2
Total per acre 42 ½ lbs.

For the drier areas Subterranean clover 2 lb. per acre should replace the Lotus major. In the North Island (Auckland Province) Paspalum dilatatum 4-6 lb. per acre may replace the Cocksfoot.

page 49

Oversowing of Hill Country and Topdressing.

Practically the whole of the deforested hill country was felled and sown prior to the setting up of pasture plant improvement work and the marketing of these improved strains under certification as to strain or type. In the early days of conversion also the thesis was expounded that only the best English grasses should be sown on the hills. It was considered doubtful in many cases whether the sowing of Cocksfoot was even justified, so great was the growth and so good the early promise on the ash of the forest burn. On the other hand there was much seed, undressed and even cleanings that went into the so called cheap mixtures for rough bush-burn country.

Since the decline of soil fertility, experience has definitely shown that lower fertility demanding species are imperative and of these Browntops, Lotus major, Danthonia and Subterranean clover have demonstrated their value.

Today also there is a marked tendency for hill country to be top-dressed with phosphate, and for this practice to be made the most of, good strains of clover in particular, should be introduced into the sward simultaneously with the topdressing. As stock-carrying increases, so will the set up encourage perennial ryegrass and crested dogstail. There has been in the past very much country sown with poor ryegrass strains which have largely run out. It looks, therefore, as though it is imperative to oversow the majority of our hills with seed to ensure the best possible opportunity for deriving the greatest advantages from phosphatic topdressing and build-up of stock nitrogen that will result as the stock carrying capacity of the country is increased.

For surface sowing the following seeds mixture is recommended:

lbs.
Certified perennial ryegrass 10
Certified Crested dogstail 3
Certified Mother white clover 1
Certified Lotus major ½
Certified Subterranean clover 2
Total per acre 16 ½ lbs.

Other species may yet find a place in this over-sowing seed formula after the trials now under way have been going for a few years.

Topdressing.

Topdressing with phosphate is the key to hill country improvement and towards its full development, and every artifice, financial, mechanical, political and industrial self-help known to man should be brought to bear to put a 2 cwt. per acre per annum dusting of phosphate on to the hills.

page 50

Hand topdressing with various devices to spread and to get the phosphate on to the hills are at present being employed. The pack horse for carrying, and bull-dozers for making tracks greatly relieve the tedium of hand spreading. Mechanical blowers may be of very great assistance but one feels the heavy load lifting aircraft will ultimately be the answer and already developmental work is in progress to explore the possibilities of developing this aid to the hills.

Conclusion.

Rain forest in New Zealand is convertible to grassland and there is a distinct correlation between the original forest cover and the grassland species that will thrive once the forest is removed. The climate that makes possible the development of rain forest is a grassland climate and it is not difficult with the aid of stock and/or fire and agricultural implements to maintain a bias in favour of grassland rather than forest. The maintenance of soil fertility at an appropriate level for high grassland production, together with strict adherence to sound principles in pasture establishment and utilization, tend to increase the stability of grassland and to make more and more remote the possibility of reversion to forest.

Progress meanwhile is far from stationary on the greater part of our hills. In the course of some 80 years a great cattle and sheep industry, store and fat stock and wool, has been built up and a forest wilderness converted to pasture. In that development the pioneer had no previous experience to guide him. He knew nothing of the processes whereby forest regenerated itself, or of the forces at work in that regeneration: he did not know that the fight could be economically won only by the use of cheap fire-stick methods and by the correct use of appropriate grazing animals: he did not realise the insidious spread of secondary growth weeds, bracken fern, hard fern, water fern, manuka, bid-a-bid, etc., under the close and continuous nibbling of the turf by sheep: he was ignorant of the correct grasses and clovers and was misled by the strong and early growth of the coarse grasses that weakened and opened up as the spurious fertility of the bush burn declined: he did not know that the part the correct sward played in the competitive struggle against the return of the forest. Nevertheless large areas went successfully to grassland: vast areas went partially to grass, part o secondary growth and part to young forest, the decline to such growths being governed mainlv by the nature of the turf and according to the accessibility of various aspects of the country to the grazing animal.

It is difficult to assess the part the working sheep and cattle dogs and the hunter pig dog, have played in the winning of forest to grass and in the keeping down of wild life that deprecated the flocks. Were it not for the inevitable dog and the horse it is safe to say the forest page 51 would never have been beaten in the wholesale manner that it was, nor would it have been farmed, even though the grass sward had in some miraculous way superseded the development back to forest. The hill country indeed owes a great debt to both horse and dog.

We may now look back and be tempted to decry as sacrilege the forest destruction as a national waste, but to the pioneer the forest stood between starvation and a livelihood in the crops and grass that could be established only on its reduction to ashes. It was a menace to be removed as cheaply and as quickly as possible. Millions of feet of timber that today would be a valuable asset went up in smoke, but for 80 years and more that deforested country has grown grass, has reared stock, has produced its annual crop of wool and stores for the lowlands to fatten; it has given livelihood to the pioneer and his grown family and their families and has contributed a main portion to our national wealth. This has built a society and given rise to cities, towns, prosperous trades, professions and industries that at the moment can offer better wages, better social facilities, better amenities in the home, better houses, etc., to the detriment of its own cause and its own existence. That country leans hard today on a handful of stalwarts, still a band of pioneers, but in an age when pioneering is more difficult and is apt to be scoffed at and adjudged the quality of the loon by its more invertebrate critics of the easy lowlands and comfortable environs of the city.

Let us make no mistake about it. If this spirit of the pioneer is killed a nation loses some hing of inestimable value and beyond replacement. It may be killed unless there is encouragement by the State and by every able-minded person who has the vision to see and to appreciate wherein the nucleus stamina of the race abides. The open, broad hill country has built a race, is still building and maintaining that race but its numbers are too few for the good of the hills to get from them their undoubted greater latent wealth. The area of our hill country could be extended by millions of acres and the per acre production could be doubled, trebled or quadrupled and at the same time the future of the hills greatly vouchsafed for the generations to come if we had the labour force and wherewithal to put into operation the knowledge in grassing, in manuring and in management that we now possess.