THE EFFECT OF DRILL WIDTH ON THE SEED PRODUCTIVITY OF LEAFY VARIFTIES OF THREE GRASS SPECIES

Three leafy grass varieties, S215 meadow fescue, S37 cocksfoot and S51 timothy. were subjected to four dril spacings of 6, 15, 24 and 36 in. under two levels of nitrogen application. Over three harvest years, meadow fescue gave better seed yields with 6- and 15-in, drill spacings. Cocksfoot gave very similar yields from 1.5, 24- and 36-in, drills but a signincantly reduced yield from 6-in, spaced drills. Timothy produced significantly higher yields at the 24 in spacing.
The three varieties showed a significant response to nitrogen application.
Aphids seriously affected the vegetative growth of meadow fescue and timothy at the wider spacings, but the 6-in. drills m boths species remained relatively free of aphid attack, as also did the cocksfoot block.     

FERTILE TILLER PRODUCTION AND SEED YIELD IN MEADOW FESCUE (FESTUCA PRATENSIS L.)

The effect of defoliation and date of nitrogen application in the spring to seed crops of meadow fescue, S215 and S53, were compared in two harvest years, in drills spaced at 18 in. S215 tillers were generally more robust than S53 tillers, and S215 produced a higher number of fertile shoots as the result of a higher conversion rate of over wintering to fertile tillers. N applied early and absence of defoliation gave the highest ratio of seed heads to over wintering tillers.
Seed- and straw-yields were depressed by April and May defoliations; May cutting had a particularly drastic effect on both varieties. S53 yields in all treatments were generally inferior to those of the hay variety, S215.
Head lengths and spikelet numbers were higher and 1000-seed weight lower in S53 than in S215.     

GRAZING MANAGEMENT FOR SEED PRODUCTION IN LEAFY STRAINS OF GRASSES

Leafy strains of five grasses were grown for seed and subjected to various cattle grazing treatments between October and April for three harvest years. The grasses were: S.143 cocksfoot, S.215 meadow fescue, S.170 tall fescue, S.59 red fescue and S.23 perennial ryegrass. All but S.59 red fescue (row crop) were studied as row and broadcast crops. The plots were sown under an arable silage crop and received top dressings of nitrogenous fertiliser every year. Yield of seed, and also quantity of herbage in winter, were measured.
October grazing in the seeding year reduced the first crop of seed in all species except ryegrass. Grazing in December improved the yield of meadow fescue throughout the experiment, and of cocksfoot, tall fescue and red fescue after the first year. Several factors might operate to bring about this effect; suggestions are made for further investigation. Repeated grazing from December to March tended to reduce vigour, and so to offset the advantage of removing autumn-grown herbage. Grazing at intervals from December to late April seriously reduced yield in all species. Tall fescue and red fescue, early flowering species, were most seriously affected, meadow fescue and perennial ryegrass least. Cocksfoot and tall fescue yielded more seed when grown in 2-ft. rows than when broadcast. Meadow fescue and perennial ryegrass did not. The yield of meadow fescue was less affected by adverse conditions than cocksfoot.     

THE EFFECT OF DEFOLIATION ON THE SEED-PRODUCING CAPACITY OF BRED STRAINS OF GRASSES

A leafy strain of timothy and of perennial ryegrass showed no significant reductions in seed yields following grazing at different dates from October to January, when extra nitrogen was applied.
Spring and winter + spring grazing, together with extra nitrogen, significantly reduced the seed yield of S50 timothy for three successive harvest years.
Perennial ryegrass S101 showed no reduction after spring or winter + spring grazing when defoliation was made not later than mid-April, but when grazing was delayed until May and drought occurred there was a significant reduction in seed yield.     

THE EFFECTS OF WHITE CLOVER AND APPLIED NITROGEN ON THE NITROGEN CONTENT OF VARIOUS GRASS/CLOVER MIXTURES

Percentages and yields of N in various grasses and grass mixtures with clover and in associated clover grown at various levels of N application over 5 years are given. Grasses varied consistently in N content, percentages being highest in meadow fescue (cv. S53) and lowest in perennial ryegrass (cv. S24). N application did not significantly affect the N percentage in clover, but the associated grasses had a highly significant effect Percentages were highest in clover associated with meadow fescue and lowest in clover associated with ryegrass. The apparent transfer of N to grass per Ib N in associated clover was calculated for various treatments each year. Reasons for the changing levels of apparent transfer from year to year are considered.     

THE YIELD AND COMPOSITION OF LUCERNE, GRASS AND CLOVER UNDER DIFFERENT SYSTEMS OF MANAGEMENT

The yields of two varieties of lucerne grown with and without each of three companion grasses, under two cutting treatments, were compared during 1956–9 to elucidate further the potential production of this crop and to clarify some contradictions in earlier results.
Du Puits lucerne (early) and its mixtures produced 20% more dry matter than the corresponding mixtures based on AF1 (late). Meadow fescue S215/lucerne mixtures were superior to lucerne grown alone in the first year, but not subsequently. Mixtures with S37 cocksfoot and S22 Italian ryegrass gave significantly lower yields.
Over three years higher yields were obtained from three cuts in the first harvest year compared with two.     

THE YIELD AND COMPOSITION OF LUCERNE, GRASS AND CLOVER UNDER DIEEERENT SYSTEMS OE MANAGEMENT

The yields of two varieties of lucerne sown alone and in associalion with each of three grasses were compared with similar red clover/grass mixtures over the period 1953–56 under two levels of nitrogenous and potassic fertilizers and two cutting treatments. The main object of the experiment was to gain a wider knowledge of the productivity and chemical composition of lucerne sown alone, and in mixtures, under relatively high rainfall conditions.
The highest production was obtained from Du Puits and its mixtures, which exceeded Grimm and S 123 red clover mixtures. The yields of the lucerne/grass mixtures were not significantly better than those of the pure sown lucerne. Under the most favourable conditions for lucerne, Du Puits eliminated practically all the sown grasses, viz., S 23 ryegrass, S 51 timothy and S 215 meadow fescue.
The application of nitrogen encouraged the growth of the grasses, often at the expense of the legume, especially the slower growing Grimm and S 123. The effect on Du Puits was less marked, but in no case was there a stibstantial increase in actual legume yield. Increasing the level of potassium, although not immediately affecting the yield, proved beneficial to lucerne survival in the later years. The protein yield from the best lucerne plots was found to be double that from pure grass swards heavily fertilized with nitrogen.
Three cuts of lucerne in the first two harvest years had a disastrous effecl on the carry-over of lucerne from the second to the third year. Both varieties of lucerne and their mixtures behaved in a similar fashion, although S 123 red clover appeared to be indifferent to these conditions. It is suggested that the cause of this was the unfavourable weather experienced in 1954.     

THE EFFECT OF A COVER CROP ON THE SEED PRODUCTION OF LEAFY COCKSFOOT S26

There was a significant reduction in the seed yield of S26 cocksfoot in the first harvest year following undersowing in oats. Yields were markedly improved, however, by the application of extra nitro-chalk in spring, by using a partial cover crop and by cutting the oats for silage.
Over three harvest years the financial returns were very similar for all treatments studied.     

THE DIGESTIBILITY AND PRODUCTIVITY OF SELECTED HERBAGE VARIETIES

Much of the published digestibility data refer to swards grown in the south of Britain. In order to study digestibility curves in a more northerly latitude, several pure swards were established in the west of Scotland in 1962 and 1963. Varieties included S22 and Tetila Italian ryegrass, S37 cocksfoot, S170 tall fescue, S215 meadow fescue, Scots timothy, English broad red clover, and SI00 white clover. In addition to primary growth in vitro digestibility, the effect of various cutting managements on digestibility and productivity was measured. Flowerhead emergence was delayed, with the result that the digestibility curve was later than is reported from southern Britain. Highest yields of digestible organic matter were obtained from the less frequent cutting regimes, but the mean digestibility of the herbage was lower. Pre-dictibility of herbage digestibility is desirable as the basis of a reliable and planned herbage utilization programme, particularly for conservation.     

A COMPARISON OF COCKSFOOT- AND TALL FESCUE-DOMINANT SWARDS FOR OUT-OF-SEASON PRODUCTION

Swards based on a mixture of SI 70 tall fescue and S215 meadow fescue were very early in spring, gave high yields for conservation in mid-season and, rested from mid-August, gave good grazing in November-December. Under this treatment, the tall fescue assumed dominance, and the swards were persistent and remained productive. The digestibility of the tall fescue swards was always higher than that of swards based on cocksfoot with which they were compared. During spring and autumn the former sward was better grazed by stock, but the position was reversed in mid-summer. Cattle grazing tall-fescue-dominant swards made better liveweight gains than those grazing cocksfoot swards during November-December.     

FERTILE TILLER PRODUCTION AND SEED YIELD IN MEADOW FESCUE (FESTUCA PRATENSIS L.)

The fertile tiller production and seed yields of spaced plants of meadow fescue varieties were found to vary widely with the time of sowing, particularly in the first harvest year. The benefit of early spring sowing is indicated in the total productivity over two harvest years.
Varieties differed in the amount of heading in the seeding year; the American type was the most prolific. This had a bearing on the relative yields in the first harvest year, since many of the potentially productive tillers of this variety were wasted through the plants becoming ripe to flower in the seeding year and, therefore, the rate of tiller production was checked. Competition within the plant appeared to be the cause of tillers remaining vegetative when conditions otherwise seemed suitable for generative development. The smaller-sized plants gave a higher proportional increase of fertile tillers at harvest than would be expected from the vegetative tillers counted in April, while at the same time there was a negative relationship at harvest from plants which had a very high number of vegetative tillers.
Infertility as reflected in a poor seed set at the time of harvest is a serious wastage of potential production in meadow fescue and, in selecting for superior seed output, breeders need to take this factor into consideration.
The 1000-seed weight varied between varieties, the pasture type being inferior to the two hay types.     

THE PRODUCTION OF EARLY SPRING GRASS

The effects of autumn management and nitrogenous manuring on the production of early spring grass were studied from 1954 to 1957 on farms throughout England and Wales.
The most important management factor influencing spring yields was the application of spring nitrogen. In the early spring 6 to 10 lb. of dry matter were produced per lb. of nitrogen applied. Autumn nitrogen increased herbage yields in the auttimn by 8 to 17 lb. of dry matter per lb. of nitrogen applied.
Italian and perennial ryegrass responded well to autumn nitrogen but it was important to graze off the extra growth fairly quickly to prevent the sward becoming too open. The yield of ryegrass swards which received spring nitrogen were very much higher if they were grazed during the previous September and October than if they had been rested during those months.
In two years neither the autumn management nor alumni fertilizer appeared to influence the spring yields of cocksfoot, timothy or meadow fescue swards, in one year, however, when autumn growth was poor, autumn nitrogen and resting resulted in slightly better yields on these swards in the following spring.
It is suggested that resting swards during September and October to build up "reserves" is relatively unimportant in relation to the yields of grass in the following spring.     

Yield profile of tall fescue (Festuca arundinacea) in comparison with meadow fescue (F. pratensis) in Finland

Yield profile characteristics of tall fescue (Festuca arundinacea Schreb.), cv. Retu, were compared with those of meadow fescue (Festuca pratensis Huds.). The study was conducted in Finland and was based on official variety trial data recorded between 1980 and 1998 at 17 trial sites between latitudes 60° and 66°N. The crops were managed according to silage‐cutting regimes. The pattern of yield formation of the tall fescue cv. Retu differed significantly from that of meadow fescue cultivars, both within a growing season as well as in sward age. Tall fescue cv. Retu established slowly, and the dry‐matter (DM) yield from the first cut, made in the first year of harvest, was significantly lower than that for meadow fescue. In the second and third years, the DM yield from the first cut did not differ between tall fescue and meadow fescue. Tall fescue produced significantly higher DM yield as regrowth (second and third cuts) than meadow fescue. The sward age significantly affected total DM production. In first‐year swards, there were no significant differences in total DM yield between tall fescue and meadow fescue but, in the second‐ and third‐year swards, tall fescue produced significantly higher DM yields than meadow fescue. The difference in yield profile between tall fescue and meadow fescue was similar in all the environments included in the study. DM yield for the first cut (kg DM ha^–1) for tall fescue cv. Retu, in comparison with meadow fescue cultivars, was 2495 vs. 3099 (P < 0·001), 3735 vs. 3741 (NS, P=0·94) and 3553 vs. 3468 (NS, P=0·30) in the first‐, second‐ and third‐year swards respectively. The respective DM regrowth yields (second plus third cut) were: 6059 vs. 5416 (P < 0·001); 5445 vs. 4221 (P < 0·001); and 5580 vs. 4113 (P < 0·001) in first‐, second‐ and third‐year swards. Total DM yields per season for tall fescue vs. meadow fescue were (kg DM ha^–1) 8554 vs. 8515 (NS, P=0·69), 9180 vs. 7962 (P < 0·001) and 9133 vs. 7581 (P < 0·001) in first‐, second‐ and third‐year swards respectively. Over the three‐year sward rotation period, which is common in Finland, tall fescue produced on average 12% higher DM yield than meadow fescue. Both tall fescue and meadow fescue suffered little winter damage in Finnish conditions; the differences between cultivars of the two species were small. The results indicated that tall fescue cv. Retu is a productive and persistent forage species suited to Finnish growing conditions.     

THE EFFECT OF CUTTING COCKSFOOT (DACTYLIS GLOMERATA L.) GROWN FOR PRODUCTION OF SEED

An experiment is described in which cocksfoot, grown for production of seed, was cut annually for 3 years in either autumn, winter or spring. No significant increases in yield of seed/ac were obtained from any treatment compared with an uncut control, and a cut in late April in one year seriously reduced the yield of seed. Additional N applied after a defoliation in October did not increase the yield of seed compared with that from plots which were cut at the same time but not fertilized. The production of tillers was not affected by cutting on any date. The percentage fertility of tillers was increased by cutting in the first year, when the number of tillers was smallest; the fertility was less consistently affected in the second year, and was generally unaffected in the third year. The weight of seed produced per ear was usually reduced by the cutting treatments. In the third year of the experiment it was shown that the penetration of light to the base of the shoots was increased substantially by defoliation, but it is deduced that maximum interception of light by the whole plant is more important for the production of seed than increasing by cutting that proportion which penetrates to the base of the plant.     

THE POSITION IN THE PLANT AND THE DATE OF ORIGIN OF TILLERS WHICH PRODUCE INFLORESCENCES

The dates of their first appearance and the dates of flowering were recorded monthly over three years from time of sowing for all tillers produced by S215 meadow fescue plants growing in simulated sward conditions in large concrete pots outdoors. The results are expressed and discussed in terms of the percentage contribution of inflorescences by tillers in relation to their chronological and ontogenetic age. The latter appeared the more important. The major contribution of inflorescences was made by primary tillers in the first harvest year, by secondary and tertiary tillers in the second year and by tertiary and quaternary tillers in the third year. The chronological age at which tillers could flower ranged from 3 to 33 mouths.     

THE EFFECT OF COMPANION GRASSES ON TIMOTHY PRODUCTION IN SWARDS CUT FOR CONSERVATION

To assess the effect of companion grasses on timothy productivity, swards of timothy sown alone or with one of eight companion grasses were harvested as for silage four times per year for two years. The companion grasses were: diploid perennial ryegrasses S24 and S23; tetraploid perennial ryegrasses Reveille and Taptoe; meadow fescues S215 and S53 and cocksfoots Trifolium and S143. Averaged over the N application rates (226, 339 and 452 kg N/ha per year) the total herhage yields of timothy/companion-grass mixtures were all significantly superior to that from timothy alone in the first year. Only perennial ryegrass S24 and the cocksfoot mixtures significantly outyielded timothy alone in the second year. Winterkill hecame evident in April of the second year and pure timothy and timothy/meadow-fescue swards were least affected. Over all swards, timothy DM increased hy a mean of 19% from the first to the second year, compared with a fall of 20% in total herhage DM. The contrihution of timothy herhage to the mixtures was very low with companions other than meadow fescue. Late-heading varieties were more compatihie than early-heading varieties, and tetraploid ryegrasses were more compatihie than diploid ryegrasses. It is concluded that if the inherently valuahle characteristics of timothy are to he exploited, it should not he sovm with aggressive companion grasses.     

THE EFFECT OF FERTILIZER NITROGEN AND FREQUENCY OF DEFOLIATION ON YIELD OF GRASSLAND HERBAGE

The effects of 4 levels of applied nitrogen, ranging from nil to a maximum of 417 lb N/ acre/annum, in all combinations with 3 frequencies of defoliation, ranging from 2 to a maximum of 10 cuts per annum, on herbage production from a perennial ryegrass/ timothy/meadow fescue/white clover sward were measured. These treatments were operative for 2J years, and in a subsequent year the residual effect of cutting frequency was tested. Dry-matter yields of total herbage and of the clover fraction are quoted, together with N yields of total herbage. Yield response to N was higher than in some other experiments in the U. K. Cutting frequency had a very large effect and, in general, the longer the interval between cuts, the higher was the dry-matter (though not the N) yield. There was a marked interaction between cutting frequency and level of N: at the high cutting frequency, dry-matter yield increased linearly with increasing level of N; at the medium frequency, response tended to fall off at the highest level of N; at the low frequency, yield declined with increasing level of N beyond 139 lb N per acre per anum.     

THE EFFECT OF GROWTH-REGULATING WEEDKILLERS ON THE MORPHOLOGY OF GRASSES

A series of experiments were carried out in 1954 and 1955 designed to investigate the effects of MCPA and 2,4-D applied at different stages of growth to grasses grown for seed. Single, spaced plants were sprayed at the rate of 1·5 lb. a.e. per acre with 2,4-D amine in 1954 and with 2,4-D amine and ester and MCPA ester in 1955. The development of the grass growing point was used as a criterion of the developmental stages at which the plants were sprayed.
Some treatments caused abnormal types of growth. S.23 perennial ryegrass and S.143 cocksfoot developed ear malformations, S.53 meadow fescue had leaf and ear malformations, while S.51 timothy showed leaf, stem and ear abnormalities.
Leaf malformations developed only after spraying when the growing points showed vegetative primordia while ear abnormalities usually appeared after treatment at most early stages of development. Stem malformation in timothy occurred after spraying at all stages in 1954, but only at the vegetative stages in 1955.
The percentage of abnormal ears in a random sample of tillers in all but one case fell as the growing point developed and most damage occurred after treatment when the apex was at the vegetative stage. Normally, treatment when glume ridges were visible on the apex produced no significant difference between the number of abnormal ears in the treated and untreated plots.
The results suggest that the chemicals act on that part of the apex which is just beginning its development but is not yet visible as a protuberance on the apex.
The type of abnormalities occurring in grasses as a result of spraying with growth regulating weedkillers is similar to those found in cereals after similar treatment.
Provided that the chemicals are applied in the 4 to 5 weeks prior to ear emergence the amount of malformation occurring in the grasses will be small.     

FERTILE TILLER PRODUCTION AND SEED YIELD IN MEADOW FESCUE (FESTUCA PRATENSIS L.)

The seed-producing capacity of two varieties of meadow fescue, S215 and S53, sown at three different spacings, was compared. One level of nitrogen was applied on three different dates in the spring. Tiller counts were made periodically during the growth of the crop. Fertile-tiller production was found to be related to vegetative growth.
The varieties differed not only in yield, but also in growth dynamics. A larger percentage of overwintering shoots became fertile in the hay variety, than in the pasture variety.
Drill spacings had significant effects on plant establishment and on vegetative-and fertile-tiller numbers. In both years N applied in March gave the highest production of fertile tillers. Date of N application did not produce marked trends in yield. The influence of spacing and date of N application on the number and density of spikelets indicated that the plant adjusted itself to environmental factors. Thus spikelet numbers were reduced in early heads with narrower drill spacing and with late applications of N. Head emergence was earlier in narrow drills, but time of N application in the spring did not produce significant differences in this respect.     

EAR-BEARING CAPACITY OF TILLERS ARISING AT DIFFERENT TIMES IN HERBAGE GRASSES GROWN FOR SEED

Three experiments are described, two with S215 meadow fescue and one with S37 cocksfoot, all grown for seed, during which all new tillers, soon after their appearance, were labelled at intervals of a month—a total of nearly 12,000 tillers. Whatever the first date of observation, the earliest tillers were always found to have contributed the largest proportion of the ears present at harvest. In one experiment applied nitrogen caused an increase in the number of tillers and ears, without however affecting the percentage contribution of the earliest tillers to the final crop of ears. The importance of the autumn period of tillering is stressed.