Grasses and Clovers of New Zealand

New Zealand Journal of Agriculture, Volume 59, Issue 6, 15 December 1939, Page 505

Grasses and Clovers of New Zealand

Ryegrass Species and their Characteristics

- By -

S. H. SAXBY.

Instructor in Agriculture, Dunedin.

(Continued from the November Issue)

♦ i—mi— mi——mi— tin— iiti——iiii—iiii—iin—mt—>nit«*<«*tiaSe Sl': ■ ' " '■ 1 | This month's article on the | 1 grasses and clovers of New Zea- f 1 land deals with grasses which T I thrive on well-drained country of = I high fertility which has a good i | supply of moisture. The differ- ’ J ent varieties and strains of rye- 1 | grass are discussed, and refer- 1 | ence is also made to some of I | the undesirable types of grasses j I which lower the production of j | feed on this type of country, j

PERENNIAL Ryegrass (Lolium Perenne).— is one of the most useful and most popular grasses for soils of high fertility. Its useful habitat range is very wide, being limited at one extreme by excessive moisture and at the other extreme by low fertility and excessive dryness.

•{♦lf— Ulf—•HU——Illi—.llll—mi—mi—mi——fill—mi—mi—-n 1* Between these 'two extremes there is a wide range of country on which ryegrass can be profitably grown. Of the factors responsible for its popularity,- the following are the most important:— (1) It is an excellent ' seed-producer, thus making its distribution both easy; and profitable. (2) It is one of the easiest and quickest 'of the grasses to establish from seed,, thus enabling it to compete •with quick-growing weeds and to be grazed much sooner after sowing than many other grasses. (3) It is highly productive under close grazing and high fertility, and is of good milk-producing and fattening value.

(4) Its maximum production is in the spring, when feed is at. a premium. (5) It will stand and thrive on comparatively hard grazing. (6) It is permanent provided that the soil fertility is kept high and that a permanent strain is sown.

A Disadvantage With all these advantages, it has the disadvantage of being dormant in the hottest part of the summer, especially when the fertility is 'low or when clovers are absent.. This may be remedied in the pasture by including in the mixture summer-growing grasses such as cocksfoot, paspalum, or timothy, all of which produce well during the time that ryegrass is dormant. Ryegrass has been sown in New Zealand for many years and on a wide range of country, much of which has been -quite unsuitable for this grass. For ryegrass, to thrive a fertile, moist but well-drained'soil is required... It will grow quite well on drier soils provided that the fertility is maintained in a high state by the encouragement •of legumes, such as white clover and subterranean clover. Of all the common grasses, ' none benefits to the same extent from the association with clovers as does ryegrass, and one of the most important

aspects of the management of ryegrass dominant pastures, is the encouragement of the clovers. ~ Because of its . quick establishing nature'and its consequent ability to be fed off' early, ryegrass dominance has too 'often been regarded as the ultimate objective on much country that is unsuited to it. On soils ( of low fertility ryegrass cannot be expected to produce well, or to remain permanent, and should- be regarded as a temporary grass ; only, the main reliance being placed on lower-fertility-demanding but permanent grasses, such as cocksfoot, browntop, or danthonia. Reasons for Failing

One frequently sees country which has been spoiled by the sowing of almost pure ryegrass. When this dies out it is replaced not by the good low-fertility-demanding grasses, but by weeds and undesirable plants. It would have been preferable to eliminate the ryegrass altogether in the beginning rather than to rely on it completely.

For the foregoing reasons ryegrass has fallen into disrepute among some farmers. It has been a failure not because it is a poor grass, but because too much has. been expected from it.

Another factor which has been responsible for varying opinions regarding the value of ryegrass as a permanent plant is the fact that in many cases short-lived strains ■of ryegrass have

been sown. For many years there was a general but unproved opinion that ryegrass harvested from certain districts produced. plants ' of a much more permanent nature than that harvested from other districts. 1 Some ten years ago a .critical examination was made of the performance of a 1 large number, of lines of ryegrass secured from all the major seedproducing districts in New Zealand, and abroad. As a result of this work it was found that there were on the

world’s markets several distinct strains or varieties of ryegrass. These varied greatly with regard to speed of establishment, time of maturity, palatability, and permanence. This, in itself, was a sufficient explanation of farmers’ varied experience with ryegrass. The Four Strains Broadly speaking, four well-defined strains were recognised. These were as | follows: (1) A permanent, low-producing .and' late-maturing strain coming from the oldest pastures in England and termed British. indigenous ryegrass. - This . strain has been tried out in experimental plots throughout New Zealand.

Its greatest disadvantage is that .it is late to begin growth in the spring, one of the greatest assets of ryegrass, as a whole, being its early spring growth. It,' however, continues growth . later . in the. summer than does ordinary ryegrass. 1 ' This experience is -general wherever ryegrass will grow. Because of its late maturity it appears to be more palatable than any other strain.

(2) A . permanent, high-producing, early-growing strain, coming from the oldest pastures in New Zealand. These were located chiefly in the -Hawke’s Bay, Poverty Bay, and Sandon districts, although some were found in Canterbury, Otago, and Southland; Because of its general good performance this type was. regarded as being ' the most suitable strain for New Zealand conditions, with the result that the strain was finally certified by the Department of . Agriculture as “Certified New Zealand Perennial Ryegrass.” Plant Selection Since . certification of perennial rye- 1 grass was begun a considerable amount of plant selection and breeding has been ; carried out by the Grassland Division of the Plant Research Bureau; with the result that there is now on the market a large quantity of this bred or selected perennial ryegrass which is certified and sold under the name of Government stock seed, pedigree seed, and mother seed. A change recently made in the certification of perennial ryegrass has resulted in several of the familiar classes being discontinued. All certified seed, with the exception of that certified in the above-mentioned classes, is now being grouped into one class, namely “permanent pasture.” Fairly Permanent (3) A fairly permanent type, the best lines of which closely approach the certified type in value. It is, however, less persistent and lower in production over a period of years. An additional

disadvantage is that under similar conditions it is attacked earlier and more severely by leaf rust than is the certified type. •’ By some it is regarded as being more palatable than the certified type. The best lines are no more palatable, and any line that is more palatable is not as permanent. As only a very small amount of this type is harvested annually, and as the demand for it is negligible, no special recognition has been given to. it, although the best lines may be certified in the commercial , class. /,

(4) A short-lived strain which, under ordinary conditions, will last for only two to four years in a pasture. -It makes very vigorous initial growth, but goes off rapidly in production after the first. year. This type is representative of the bulk of the world’s ryegrass seed. For permanent pastures this type is quite unsuitable, but is fairly satisfactory for pastures of two years’ duration. . . ' . Palatability The less permanent strains of ryegrass are more palatable than the permanent ones. This is very noticeable when they are grown side by side. .Palatability is dependent on many factors, the most important being the strain sown, the stage of growth at which the pasture is fed off, and the health of the ryegrass itself. The two last-named conditions can be adjusted fairly readily, and little trouble is experienced when the ryegrass is made to produce short, succulent growth as the result of close grazing and an ample supply of nitrogen, which is. supplied by a vigorously growing clover. A definitely unpalatable paddock of ryegrass indicates one of two things unsatisfactory management or unsatisfactory soil conditions of moisture and fertility. . •

Summarised, the position of ryegrass in our pastures is as follows: — Ryegrass may be profitably sown ' on a wide range of country provided that the clovers form a good proportion of the sward. Where vigorous clovers can be grown, so can peren- . nial ryegrass be grown. Perennial ryegrass is distinguished from Italian ryegrass in the vegetative state by the fact that the leaf shoot is folded and not rolled as in Italian ryegrass.' The ligule is small and the ears, although variable, are seldom as large as in Italian ryegrass. In the flower heads they may be readily distinguished by the presence or absence of awns. Awns are frequently known as “whiskers” or “tails,” and are pointed extensions of what is commonly regarded 'as the seed. These are well developed in Italian ryegrass, and absent in perennial ryegrass. In some of the poorer types of ryegrass a small number of poorly-developed awns may be found on some parts of the seed head. ‘ Italian Ryegrass Italian Ryegrass " (.Lolium multiflorum). is the most useful and the highest producing of our short-lived grasses. Its habitat range is similar to that of perennial ryegrass, although it will not thrive under such hard conditions. For its maximum, development a deep, rich, and well-drained soil is required. Like perennial . ryegrass, it becomes very

low .in production when at all waterlogged' or when the supply of nitrogen is low. : .■■ ; ~ The nitrogen essential for the growth of Italian ryegrass is, in the first. instance, generally made available by the various . operations of cultivation, but after six months or so this is frequently all used, and unless a further supply is available production of vigorous herbage ceases. This nitrogen may be best supplied through clovers, such as white clover, red clover, or subterranean clover. Red clover,- because of its rapid establishment and good, high-yielding hay qualities, is usually associated with Italian ryegrass, but provided a good establishment is secured white clover is quite satisfactory. Where Italian ryegrass is being grown on subterranean clover country a considerable degree of success may be secured by drilling in the Italian' ryegrass on an established subterranean clover pasture in the early autumn.

Further Value Although Italian ryegrass is used chiefly as the main ingredient in temporary pasture mixtures, it is also valuable as an additional species in a general pasture mixture, when the addition of 5 lb. per acre will provide earlier feed than a mixture without Italian ryegrass. Up to 10 lb. per acre may be sown, but care should be

taken that the pasture is fed off sufficiently early to prevent smothering of the slower-establishing grasses and clovers. When sowing pastures from which it is intended to harvest perennial ryegrass seed, Italian ryegrass should not be. sown, as the practice of sowing and harvesting the two together has been responsible for the deterioration in' type .of much of the \ South Island perennial ryegrass. The identification of this grass .is discussed under perennial ryegrass, where the differences between the two are pointed out. The main difference is in the rounded sheath and the rolled leaf shoot of the Italian ryegrass. Questionable Value f Western Wolths Ryegrass is a variety of Italian ryegrass and was originated in Holland. Its .useful life is restricted to one year at the most, and on this account its value, even for temporary pastures, is very questionable. Up to the time of its first grazing it will produce more feed than Italian ryegrass, but after this its production becomes less and less in comparison. There is no way of distinguishing western wolths from Italian ryegrass unless the two are growing side by side. The seeds are also indistinguishable, and the length of the awns on various samples indicates nothing. When the awns have been removed by hard 'threshing or dressing it is not possible to decide whether the - seed is perennial, Italian, or western' wolths ryegrass. Consequently, this has resulted in all three grasses being unconsciously sold and harvested under any one of the three names, the ultimate naming of the line of seed depending not on the type of plant but on the size and frequency of occurrence of awned seed. ‘ No Guarantee The result of this has been that many lines of, say, Italian ryegrass contain

a mixture of both perennial, Italian, and western wolths ryegrass. ■ Sometimes one finds lines of seed which are bought or sold as, say, western wolths turning' out to be a form of perennial or a line sold as perennial turning out to be a line of Italian. From this it can. be seen that a farmer ordering any one of these three on the open market 1 has absolutely .no guarantee that he is getting what he specified. 1 Results of Tests Some years ago a large, number of commercial samples of Italian ryegrass and western wolths were collected and tested. . Of those sold as Italian ryegrass,, one-quarter were chiefly Italian ryegrass, two-thirds were chiefly l western wolths, and. the remainder were perennial. Of those sold as western wolths, less than onequarter were chiefly western wolths, two-thirds were chiefly Italian, and the remainder were perennial. Of the whole lot tested, very few lines .were found to be purely of one type. Genuine western wolths is practically non-existent on the New Zealand market. ■ .

The position with Italian ryegrass was much the same. The purest and most vigorous lines of this have been increased under the Department’s certification -scheme, and any farmer requiring genuine Italian ryegrass is strongly advised to procure certified seed. The questionable value of western wolths has not warranted the certification of it. Prairie Grass (Bromus Unioloides). — Although this grass will grow on fairly dry soils, it will thrive only on rich, warm country. It is an erect, tallgrowing perennial plant that ,is eaten readily by all classes of stock. The most important feature regarding prairie grass is that in the warmer , districts of New Zealand it produces . a large amount of feed during the late autumn, winter, and spring. This feature alone makes this grass of great value in special circumstances, such as the winter production of milk in districts where winter growth is possible. As prairie grass is eaten so readily by stock it is useles to'sow it in a general mixture of other grasses, as it dies out very rapidly under close, and selective grazing. In sowing down

prairie grass pastures it should always be the dominant grass so that the pasture can be managed accordingly. Provided that it is dominant and that it is not . eaten too closely, prairie grass will remain in a pasture for many years because of > its tussock habit and vigorous growth' smothering out other competing grasses. Grazing Practice Grazing should never be severe on these pastures. Growth should be allowed to reach a height of a foot or more before grazing, which should seldom be closer than three to four inches from the ground. On second-class soils of low fertility, prairie grass makes little growth, but on good soils (and where there is an abundant supply of nitrogen) it will thrive. On this account l the .sowing of clover is essential for the production of a large quantity of nutritious feed. ■ Prairie grass, like other grasses of a similar habit of growth, will remain dominant in a pasture and smother out lower-growing grasses if it is allowed to reach its maximum development occasionally. For this reason

occasional hay crops will benefit a prairie grass pasture. . z Prairie grass is sometimes confused with cocksfoot, as both have flattened sheaths, long ligules, and under some conditions a very similar bright green colour. Prairie grass, however, is always somewhat hairy, more especially on the sheath. Cocksfoot is hairless.' . . Meadow Fescue Meadow Fescue (Festuca Pratensis). Although used to a considerable extent in America and European countries, this grass has not given satisfactory results in New Zealand. Except when the flower heads are showing, it is very difficult to distinguish it from Italian 1 ryegrass, and in many instances this difficulty of recognition has almost certainly been responsible for its apparently poor behaviour. Meadow fescue is a fairly tallgrowing and vigorous grass, and requires a rich soil in order to thrive. The herbage it produces is coarse, but is eaten quite readily. Meadow fescue is slow to become established, taking some three, years to reach full development. Quite good pastures of meadow fescue are occasionally seen in this country, but when grown under similar conditions to perennial ryegrass it does not make as good a sward or produce as much feed under, close-grazing. 1 Further investigations are required regarding this grass in New Zealand because of its reputation in other coun-

tries, where it is regarded as being a high-yielding permanent grass well suited for permanent pastures on moist, fertile soils. , Identification . The identification of meadow, fescue is rather difficult, as it is similar to Italian ■ ryegrass in most vegetative characters. The chief difference is in the shape,of the small bud at the base of the plant. This bud is very small, and is only, about one-fifth of an inch long. ’ In Italian ryegrass it is long

and narrow, whereas in meadow fescue it is short and stumpy. This is a fine difference, but is the only reliable method of differentiating these two grasses in the vegetative' state. When in flower, however, they'are considerably different. The. flower head of Italian ryegrass is a single unbranched spike, ' whereas that of meadow fescue is branched. For Warmer Climates . Paspalum Dilatatum. —This grass ; belongs to a group, 1 the majority, of which are natives, of tropical or semi-tropical climates. It thrives only/ in districts which experience a warm summer and have a fairly high annual rainfall. On this account it is of most value on the North Auckland . peninsula and" on the coastal districts of the Auckland Province, although it can be grown with a fair measure of .success in Hawke’s '• Bay and Taranaki. It has also been grown as far south as Hokitika. Paspaium is a high-producing perennial and twitchy grass, the herbage of which is relished by all classes of stock. It is essentially a summer grass, as its production period spreads from December to March, during which time a large amount of feed is produced: The value’ of this grass has been debated for many years, but it is now generally agreed that, with correct management, it is giving satisfactory results and will combine quite well with other species, such as ryegrass, white clover, and subterranean clover. ; ; .

The essential features in the management of paspalum are topdressing to encourage the clovers and the control of surplus growth with the mower. No Spring Growth Pure paspalum pastures are not as satisfactory as. mixed pastures because of the absence of spring growth in paspalum. A mixed ryegrass and paspalum pasture is quite satisfactory, as the ryegrass gives a good quantity of winter and spring feed when the pasture is dormant; leaving the latter to take up the running when the ryegrass is at its low production period in the heat of the summer. Paspalum pastures are very liable to become sod-bound, with a consequent falling-off in production. This was one of the main objections to paspalum for many years. l Sod-bound pastures may. be greatly increased in production by the surface sowing of ryegrass, white clover, or subterranean clover on The pasture after the sod has been broken. This may be carried out by heavy winter stocking, ploughing in narrow lands, discing, or by heavy harrowing.'. ; When sowing paspalum in a . general mixture, autumn sowing is preferable as the other species, together with a small proportion of the paspalum seed.

will germinate rapidly and afford a cover for the slower germinating paspalum, which will come through when the warmer weather comes in the following spring. The paspalum . pasture may be thickened up considerably by allowing it to run to seed the following summer. . ' Paspalum dilatatum may be recognised by its fattened sheath and large ligule, around which are a number of hairs, and its long rhizomes. Nuisance in Crops Kentucky Bluegrass (Poa Pratensis) —Although this is an important grass in parts of America, its sphere of usefulness in New Zealand is very limited. It is a perennial grass that is slow, and difficult' to establish, but when once growing well, it will spread rapidly by means of strong-growing underground runners, thus making it a twitch grass. - , In common with other twitches, it will thrive on loose, friable soils, and reaches its maximum development where there is an ample supply of moisture and where the summers are warm. Under warm, dry conditions its production is very low. The districts in which it thrives are therefore very limited, and are confined mainly to irrigated areas where the. important moisture supply can be regulated. Here it is a very useful pasture grass, but as a farm grass it is a nuisance because of its competition with lucerne and annual crops.

The only other conditions under which Kentucky bluegrass is of much value is on hill or sand country, where a binding agent is required on loose, exposed faces. Once established here, it will make a firm sward, and although its production is not high, it will at least prepare the ground for the establishment of better grasses, such as cocksfoot. Hard to Eradicate Kentucky blue grass should not be sown on country which is likely to be brought into cultivation at any time because of the difficulty experienced in eradicating it. , The other grasses with which this may be confused have been discussed under rough-stalked meadow grass. The main characteristics of Kentucky bluegrass are a twitchy nature and dark green leaves of a typical poa shape. The ligule is small, and the sheath and leaf shoot ■ are flattened. There are no ears. Another Twitch Red Top (Agrostis Stolonifera, var. Major) —This grass is very closely allied to browntop and creeping bent, and is to be found in scattered localities throughout New Zealand. It is

a true twitch—that is, it spreads by means of rhizomes or underground creeping stems. Under fertile conditions it produces a fair quantity of second-rate. feed. Being of a twitchy nature, it will thrive only in loose textured soils. It has been tried out on hill country to a considerable extent, but has never been found to produce as satisfactory or permanent a sward 1 as browntop, as consolidation prevents its spreading. A certain amount of redtop was at one time imported for the sowing down of lawns and playing areas, but because of its coarse . nature and poor turfforming qualities it has given place to the much better grasses, browntop and Ch ewings fescue. As a pasture ! plant redtop is useless. On good country where it ■’will thrive, it is an undesirable twitch of lower production 1 and poorer quality than ryegrass. On poor country it will persist as a stunted, spindly plant which produces very little feed.' The sowing of redtop is not justified under any conditions. Redtop is distinguished from browntop by its much' longer ligule, its

twitchy habit, and coarser leaf. It differs from creeping bent in that it has underground creeping stems, whereas those of creeping bent are overground creeping. It is also a

much coarser type of plant. The sheath and leaf shoot are round in. section. Ears are absent. Heavy Winter Stocking Annual Poa (.Poa Annua). This is an annual volunteer grass which is frequently found throughout New Zealand in open pastures and waste places. Although it is relished by stock, its short life and its low production cause it to be regarded as of little value. In

most parts it may be seen flowering and reseeding during practically any month in the year. ■ It is frequently prominent in pastures that have been heavily .stocked and poached in the winter. This opening up permits the growth and rapid spread of this grass. It also comes into pastures on heavy soils which are sown with short-lived strains of pasture plants. As if will not , stand competition, poa annua in these pastures is usually replaced ' by the more permanent grasses and weeds which are aggressive but slow-estab-lishing. ' . Generally speaking, the presence of pda annua indicates . heavy winter stocking ,or a transitional stage in a pasture life, this stage being between the time that the . temporary sown elements die out and the time that the final permanent elements are thoroughly established. For identification * purposes, poa annua has a useful' and characteristic feature in an obvious waving or. crinkling half-way along the leaf, which is dull on both surfaces. It is very shallow rooted and non-creeping. Ears are absent. Both surfaces of the leaf are dull in contrast to poa trivalis, in which the lower surface is shiny. The ligule is long and'white, and the sheath and leaf shoot are flat in section.. (To be continued)

Outstanding Results From Irrigation

The irrigating of swede crops on, the Levels plain was very successful last season with the result that this, light stony land produced crops unseen' 1 before on this area. The failure of the majority of the crops in the rest of the district due to dry conditions further added to the value of the crops which sold at up to £lO per acre for feeding purposes. ' . ”

Because of the shortage of paper supplies caused by the war it has been necessary to use a different type of paper in this issue of the “Journal.” It is hoped that further supplies of the paper usually used will be on hand for the January issue.