The effect of companion perennial ryegrass cultivars on red clover productivity when timing of the first cut is varied

Replicated plots of Hungaropoly red clover were sown on a sterilized area in May 1975 alone (seed rate 11 kg ha^-1) or with one of six cultivars of perennial ryegrass (seed rate 3·5 kg ha^-1) viz. Cropper and S24 (early heading), Barlenna and Hora (medium heading) and Melle and Perma (late heading). In 1976 and 1977 primary growth was cut at one of four dates ranging from mid-May to mid-June and thereafter plots were harvested twice each year.
Varying the time of first cut did not have a significant effect on total dry matter (DM) yield in either year despite differences in means of cutting treatments on annual red clover yields of the order of 6–9%.
In some companion grass treatments total DM yield in 1976 was increased and total red clover yield and percentage red clover contribution were reduced relative to swards sown only with red clover. In 1977 a similar but non-significant trend was found. Swards containing early ryegrasses had higher total herbage DM yields but lower red clover yields and contents than all other swards at the first harvest in both years.
Delay in date of taking the first harvest in 1976 reduced DM digestibility in the first cut and increased it in the second in both years.
It is suggested that by cutting early and increasing the number of harvests from three to four per year, differences in the content of red clover between the first and second cut might be reduced, and it is concluded that more benefit is derived from red clover when medium or late heading ryegrasses are used as companion grasses.     

Establishment, persistence and nitrogen fixation of white clover and marsh trefoil on blanket peat

White clover (cv. S184 or Blanca) or marsh trefoil (cv. Grasslands 4703 or Grasslands Maku) were sown alone and in combination with a companion grass (tall fescue, red fescue, perennial ryegrass or ryegrass cleanings) on a peat area of hill land originally dominated by Juncus articulatus and Molinia caerulea.
Lime and ground rock phosphate were applied in 1973, the area rotavated to a shallow depth and seeds sown in May 1974. No fertilizers were applied except at sowing time and two harvests were taken per annum for 4 years.
Differences in yield and legume content between companion grass treatments were small. After the first full harvest year Blanca swards usually had the lowest DM yields and those containing Maku the highest. The contribution of marsh trefoil to total herbage yield increased from 4·2% in 1975 to 22% in 1978, whereas white clover decreased from 4·2 to 1·2%. Legume yields in 1978 were less than half those in 1977. Overall, N yields were low, Maku swards fixing most N estimated to be highest in 1977 at 35 kg ha^-1.
It is concluded that marsh trefoil grows well on upland peat but more information on its response to grazing is necessary before conclusions can be drawn about its value in hill land improvement.     

A COMPARISON OF THE HERBAGE YIELD OF ITALIAN RYEGRASS AND TALL FESCUE MIXTURES IN THE SECOND AND THIRD YEAR AFTER SOWING

The annual yield of tall fescue was higher than that of Italian ryegrass in the third year after sowing, but the total yield of herbage from grass plus clover swards was similar.
In both the second and third year after sowing, the yield of herbage in the spring grazing was higher when fescue was used as the sown grass. The method of establishment of both tall fescue and Italian ryegrass affected the total and seasonal yield in the second and third year after sowing, but the magnitude of these effects was not nearly as marked as it was earlier in the life of the leys. In the second year after sowing, swards of both Italian ryegrass and tall fescue had a higher yield of total herbage and of white clover, and a lower ingress of unsown species, when established without a cover crop and grazed frequently in the year of sowing.
The inclusion of red clover did not increase total yield of DM in the second and third year after sowing, and it slightly decreased the yield of the tall fescue mixture in the third year following sowing when N was applied. S170 tall fescue was readily grazed by sheep in spring and autumn.
The apparent recovery of applied N varied with the mixture sown, and the management given during establishment.     

Herbage production from swards containing a range of grass, forb and clover species and under extensive management

Three small plot experiments were conducted to investigate the effects of species of grass and forbs, defoliation regime, inclusion of white clover and forb blend on the herbage dry matter (DM) yield, botanical composition and mineral content of swards managed with zero fertilizer inputs. The results of all three experiments were characterized by decline in herbage production and large variations in treatment effects over the harvest period.
When sown singly with a standard grass mix the species that competed well with grasses and produced annual forb herbage yields greater than 20 t DM ha⁻¹ were black knapweed, oxeye daisy, ribwort plantain, burnet, birdsfoot trefoil, chicory, kidney vetch, red clover and white clover. When sown singly with a standard forb mix, grass species significantly affected the annual yield of total ( P <005). grass ( P <001) and forb ( P <0.001) herbage. The species that most surpressed the yield of forbs were common bent, Yorkshire fog and perennial ryegrass. Those that allowed for the highest yield of forbs were rough meadow grass, sweet vernal grass and crested dogstail. Averaged over the three harvest years, defoliation regime did not significantly affect herbage production, but the inclusion of white clover in mixtures increased the yield of grasses ( P <0.01) The use of rosette-type forb blends increased forb yield ( P <0.01), compared with erect-type blends.
The effects of treatments on herbage N and mineral contents and yields were inconsistent. However, there was some evidence to support the view that the presence of forb species in swards can result in greater contents of minerals in herbage, compared with grass-only swards.     

Effect of fertilizer nitrogen on six-year-old red clover/perennial grass swards

Three diploid red clover cultivars—Sabtoron, Violetta and Essex—and three tetraploid, Hungaropoly, Teroba and Red Head, were sown separately in pure culture and with each of three companion grasses: timothy (Aberystwyth S48), tall fescue (Aberystwyth S170) and perennial ryegrass (Aberystwyth S24).
The effects of fertilizer N on yield and on clover/grass ratio over a 2-year period (seventh and eighth harvest years) subsequent to 6 harvest years during which no N fertilizer was applied were investigated. The data for productivity and persistence have already been published (McBratney, 1981; 1984).
Application of fertilizer N increased DM yields in the eighth year. In this year, the highest yield, 11·9t ha^-1, averaged over the six clover cultivars, was given in association with tall fescue. Tall fescue contributed 90% of this yield. Clover content continued to decrease in all swards but the decrease was greatest in the swards receiving fertilizer N. The yield of clover DM averaged over the six cultivars under N treatment declined from 5·6t ha^-1 in the seventh year to only 0·4t ha^-1 in the eighth year.
The results from this trial demonstrate the potential of red clover sown either pure or in mixture with a suitable perennial grass, to maintain high output of quality herbage over a 6-year period without the aid of fertilizer N. They further demonstrate that following decline in red clover content, both herbage yield and quality may be restored by the application of N fertilizer, particularly where the clover was seeded with a highly productive companion grass.     

A comparison of the herbage productivity of Bromus wildenowii cv. Grasslands Matua with four cultivars of Lolium perenne when grown in association with Trifolium repens

In a small-plot trial five grass varieties bromegrass cv. Grasslands Matua, perennial ryegrass CVS. Melle (diploid) and Bastion, Condesa and Meltra (tetraploid) were established as grass/white clover swards with white clover cv. Menna. Productivity was measured under 6-weekIy cutting both without N fertilizer (N_o) and with 100 kg N ha^?1 applied in spring (N₁₀₀) Evaluation was made over 2 harvest years, 1986–87. Total mean annual production of herbage dry matter (DM) in the first harvest year at No and N_o was 5·07 t ha^?1 and 6·93 t ha^?1 respectively. In year 2, corresponding values were 11·81 and 12·67 t ha^?1. In year 1, Matua swards at N_o and N₁₀₀ yielded 5·08 and 6·65 t DM ha^?1 compared with 507 and 70 t DM ha^?1 for the mean of the four ryegrass varieties. In year 2, corresponding values were 12·90 and 12·29 for Matua and 11·54 and 12·78 for the four ryegrasses. In year 1, the digestable organic matter in the dry matter (DOMD) of the Matua swards was lower than that of Melle, Bastion and Condesa at N_O, particularly at the first cut. In year 2, differences in DOMD between treatments and varieties were not significant. The proportion of white clover was found to be higher in the N_o than the N₁₀₀ treatment, and also higher in year 2 in most treatments. For the _No treatment Matua swards had the highest proportion of white clover in year 1 (32% compared with 24% for the mean of the ryegrass varieties) but the lowest proportion in year 2 (27% compared with 60% for the ryegrasses). For the N_o treatment in year 1 clover production was also 43% higher, on average, from the tetraploid treatments than with Melle as the companion grass; for this comparison in year 2 the differences were not significant. It is concluded that Matua bromegrass/white clover swards receiving no N fertilizer may have a good potential under cutting management. However, the evidence from this trial is that in the second year the proportion of white clover is lower with Matua swards than with perennial ryegrass as the companion grass.     

Yield and stability of yield of single- and multi-clover grass-clover swards in two contrasting temperate environments

Diversity of clovers in grass-clover swards may contribute to greater herbage yields and stability of yield. This possible effect was evaluated in an experiment carried out over three harvest years at two contrasting sites, differing in precipitation and soil composition, using mixed swards containing either one, two or three clover species sown together with timothy ( Phleum pratense L.) and meadow fescue ( Festuca pratensis L.). The clover species were red clover ( Trifolium pratense L.), white clover ( Trifolium repens L.) and alsike clover ( Trifolium hybridum L.) sown in various proportions in a total of ten treatments. All swards were fertilized with nitrogen with amounts that increased from year to year, and three harvests were taken in three consecutive years. There was a significant interaction between site and species mixture on total dry matter (DM) yields (range 27–32 tonnes ha⁻¹) and DM yields of clovers (range 5–15 tonnes ha⁻¹); red clover as a single species or in a mixture was superior at the dry site while multi-clover species mixtures were superior at the wet site. Alsike clover was the least productive species of clover. Stability of yield of clovers was generally higher by including white and red clover in the seed mixture but total DM yield was not.     

The comparative performance of Holcus lanatus and Lolium perenne under sheep grazing in the Scottish uplands

An experiment was conducted over 3 years (1983-85) to assess the performance of Holcus lanatus German Commercial and cv. Massey Basyn compared with Lolium perenne cv. Perma on a gley soil under sheep grazing in the Scottish uplands. All grasses were sown together with Trifolium repens cv. Grasslands Huia. The swards were rotationally grazed at similar herbage allowances. During the first harvest year, the swards were grazed hard to a low mass (500 kg DM ha⁻¹). In the second harvest year, post-grazing herbage masses of 500 and 1000 kg DM ha⁻¹ were compared.
Perma ryegrass had a higher level of herbage production than both H. lanatus cultivars in the first and second harvest years after sowing and hence had a greater number of sheep grazing days. The ryegrass sward consisted of 25% more green sown grass (85 cf. 60%) but 12% less white clover (4 cf. 16%) compared with both H. lanatus cultivars in the establishment and first harvest years. The persistence of all three grasses was poor although ryegrass had a higher presence (36%) than either Massey Basyn (22%) or German Commercial (13%) at the end of the. second harvest year.
At a similar herbage allowance, there were no significant differences in the herbage intake and liveweight gain of sheep. Ryegrass had a higher organic matter digestibility and lower neutral and acid detergent fibre and lignin contents than either of the H. lanatus cultivars.
In the second harvest year, although herbage production was greater at the higher herbage mass, there was no difference in the proportion of sown grass.
It was concluded that ryegrass is a superior grass to H. lanatus on upland soils with high N status, moderate P status and a high pH.     

Productivity of red clover grown alone and with companion grasses; further studies

Three diploid—Sabtoron, Violetta and Essex—and three tetraploid—Hungaropoly, Teroba and Red Head—red clover cultivars were sown alone and with each of three companion grasses—timothy (S48), tall fescue (S170) and perennial ryegrass (S24). The productivity and persistence of the red clover cultivars were compared. Results obtained over the first four harvest years were presented in an earlier paper (McBratney, 1981) and this paper presents results from the fifth and sixth (final) harvest years.
The low yield obtained in the fifth and sixth year from Essex under each seeding treatment indicated a deterioration in its persistency or vigour or both. In the fifth year the remaining two diploids, Sabtoron and Violetta, were as highly productive and persistent as the three tetraploids but in the sixth year the decrease in productivity was greater in the diploids than in the tetraploids. In the fifth year Teroba, the highest yielder, produced 9 8 t total DM ha⁻¹ over all seeding treatments of which 73% was clover DM; in the sixth year Teroba was again highest yielding, producing 9.3 t ha^−l with 67% clover content. Tall fescue was the most consistent companion grass in the mixed swards, in the sixth year contributing 53% grass DM to the total 8 8 t DM harvested ha⁻¹.
The trial demonstrates the potential of a number of red clover cultivars grown either pure or with a suitable perennial grass to achieve and maintain a high output of herbage of good quality over a period of 6 years without any application of fertilizer N. The practical agricultural implications of using red clover are discussed.     

Spring and autumn establishment of Caucasian and white clovers with different sowing rates of perennial ryegrass

The effect of sowing date (SD) and sowing rate of perennial ryegrass (PRG) on the establishment of Caucasian and white clovers in New Zealand was assessed. Clovers were sown in spring on 24 September (SD1) and 9 November (SD2) 1999, and in autumn on 4 February (SD3) and 31 March (SD4) 2000. On each date, clovers were sown with 0, 3, 6 or 12 kg ha^?1 of PRG. Total herbage dry matter (DM) production up to 6 November 2000 was 13–16 t DM ha^?1 for SD1 and SD2 when sown with 3–12 kg ha^?1 of PRG, and 7–10 t DM ha^?1 for sown clover monocultures. For SD3 and SD4, total herbage production was 6–9 t DM ha^?1 with PRG, while total herbage production of clover monocultures was 5·4 t DM ha^?1 for SD3 and 2·6 t DM ha^?1 for SD4. By 6 November 2000, white clover contributed proportionately more than 0·15 of herbage mass when sown with 3–12 kg ha^?1 of PRG on SD1, SD2 or SD3, but less than 0·09 when sown on SD4. The proportion of Caucasian clover never exceeded 0·09 of herbage mass in any of the swards. White clover was successfully established in spring and in autumn with 3–12 kg ha^?1 of PRG provided the 15‐mm soil temperature was above 14 °C. None of the combinations of Caucasian clover and PRG provided an adequate proportion of legumes during the establishment year. This unsuccessful establishment of Caucasian clover with PRG was attributed to its inability to compete for available light as a seedling due to slow leaf area expansion from secondary shoot development and a high root:shoot ratio. Alternative establishment strategies for Caucasian clover may include the use of slow establishing grasses, cover crops and temporal species separation.     

Cattle slurry as a source of nutrients for red clover: herbage production and clover contribution

An established sward of red clover cv. Hungaropoly sown pure received approx. 30 kg P ha^-1 and 200 kg K ha^-1 each year for 3 successive years. The P and K were applied either as cattle slurry, inorganic fertilizer or combinations of these. Treatments were applied either in spring or after the first harvest. There were a total of six treatments and these were harvested three times each year. The average yields of total herbage DM over all the treatments in the first, second and third years were 15·2, 14·2 and 14·2 t ha^-1 respectively and the various treatments had no significant effect on the overall yields.
Treatments had a significnt effect on red clover DM yields and percentage red clover in one harvest in each of the first 2 years and all three in the third year. Yields of red clover were lower and grass higher in treatments receiving cattle slurry only. On this treatment there was a total yield of 23·2 t ha^-1 red clover DM in the 3 years compared with 30·2 t ha^-1 on the inorganic fertilizer treatments. However, by applying P and K fertilizer in the spring, followed by cattle slurry after the first harvest, it was possible to maintain a high proportion of red clover in the sward and to produce yields of red clover DM similar to those on the inorganic fertilizer treatments.     

A COMPARISON OF THE REACTION OF DIFFERENT GRASS SPECIES TO FERTILIZER NITROGEN AND TO GROWTH IN ASSOCIATION WITH WHITE CLOVER. II. YIELD OF NITROGEN

Seven species or varieties of grass, and a mixture of 3 of them, were sown in pure swards, treated with 4 levels of nitro-chalk (0, 17·5, 35, and 70 Ib N/ac/cut) and cut 4 or 5 times each year. Each species and the mixture were also sown with white clover, and the effect of fertilizer N on the yield of N in each grass was compared with the effect of clover on the yield of N harvested from the grass/clover swards.
The regression line for response in yield of N with increasing levels of fertilizer N showed slight, but significant, upward curvature. The grasses differed in their uptake of N from the soil, S37 cocksfoot and S48 timothy showing relatively high uptakes, and the ability of each grass to take up fertilizer N was usually related to its uptake of N from the soil. Differences in the yield of dry matter between the species, at a similar level of N, are discussed, and it was concluded that perennial ryegrasses were most efficient and Agrostis tenuis was least efficient in using the N taken up in the production of DM.
In general, there were no significant differences between the yields of N of the grass/clover mixtures; the N yields of the grass components were significantly different and tended to be inversely related to the N yields of clover.
Grasses which gave high yields of N with fertilizer were also high yielding when grown in association with clover. Pure grass swards required more than 200 Ib fertilizer N/ac/yr in order to yield the same amount of N as the grass/clover swards. The amount of N estimated to have been derived by grass from clover (indirect effect of clover) increased each year; it was highest with S37 cocksfoot and lowest with Irish perennial ryegrass, averaging 46 and 23 Ib N/ac/yr, respectively.     

The effect of strategic use of fertilizer nitrogen in spring and/or autumn on the productivity of a perennial ryegrass/white clover sward

The productivity of a mixed sward, comprising perennial ryegrass cvs Barlano and Bastion and white clover cvs Donna and Aran, was measured under sixteen fertilizer N treatments. These involved 0.25, 50 and 75 kg N ha^-1 in spring only, in autumn only and in all combinations of spring N and autumn N. A simulated grazing regime of six cuts annually at 3- to 6-week intervals was imposed. Increasing rates of total N application increased total herbage DM regardless of application pattern. Yield response was greater with N applied in the spring, and total herbage DM was higher with high spring N-low autumn N than the reverse. Mean yield responses at the first harvest to 25, 50 and 75 kg ha^-1 N in spring were 13.6, 10.8 and 11.6 kg DM per kg N. Corresponding responses at the final harvest to N rates in the autumn were 7.2, 5.8 and 6.8 kg DM per kg N. Responses were similar at these times for treatments receiving combined spring and autumn N. Over all treatments, mean annual production of total herbage was between 7.08 t ha^-1 DM with no N and 8.19 t ha^-1 with 75 kg ha^-1 N in both spring and autumn. Owing to drought, mean production in year 2 fell by 32% compared with year 1. White clover production fell progressively with increasing N application. Treatments with spring-applied N gave the most marked decrease. White clover was more markedly depressed than the associated grass by the drought in the second year. The mean reductions in white clover content were 0.17, 0.07 and 0.12 percentage units per kg applied N for spring N, autumn N and combinations. Autumn N use depressed white clover less than spring N but the yield response of grass was less. It is concluded that any applied N adversely affects white clover performance to some degree. Where management factors are unfavourable to white clover even strategic N use may not be wise. Instead, it is suggested that a ‘dual-sward’ approach be adopted in practice, namely, grass/white clover swards with no N. and complementary grass swards receiving optimum applied N to give better production at times when grass/white clover swards are relatively less productive.     

Optimizing legume content and forage yield of mown white clover–Italian ryegrass mixtures through nitrogen fertilization and grass row spacing

Mixed swards of white clover–grass mixtures in highly productive environments often fail to reach the minimum recommended annual clover proportion of about 0·30. This study assessed the effect on clover content and total dry matter (DM) yield of two spring N applications (0 and 45 kg N ha^?1) and two distances between drilled grass‐rows (0·18 and 0·36 m) over 3 years for mown swards of white clover–Italian ryegrass (Trifolium repens–Lolium multiflorum) in binary mixtures in northern Italy. An additional aim was to determine the advantage of association of grass–clover compared with grass and clover monocultures. On average, N fertilization of mixtures resulted in almost 9% higher total yield (P < 0·01; mean response = 18·1 kg of total DM per kg of N) but decreased the clover proportion (0·250 vs. 0·312). Wider grass‐row spacing increased clover proportion (0·327 vs. 0·234; P < 0·01) with no reduction of total DM yield. N fertilization × grass‐row spacing interaction occurred only for clover content (P < 0·01). Without N fertilization, mixtures out‐yielded clover and grass pure stands. With N fertilization, at double rate to pure grass, yields from mixtures were greater than from clover and comparable to Italian ryegrass.     

Effect of seed rate of red clover and of companion timothy or tall fescue on herbage production

Tetraploid red clover (cv. Hungaropoly) was sown at seed rates of 6,12 or 18 kg ha^?1 alone and in mixture with timothy (cv. Scots) at 2, 4 or 6 kg ha^?1 or with tall fescue (cv. S170) at 6,12 or 18 kg ha^?1. Two ‘silage’ crops and an ‘aftermath grazing’ crop were harvested in 2 successive years. In harvest years 1 and 2, total herbage production levels of 11.12 and 7.47 t dry matter (DM) ha^?1 respectively were obtained from pure-sown red clover compared with 11.84 and 8.78 t DM ha^?1 for red clover-timothy and 12.23 and 9.64 t DM ha^?1 for red clover-tall fescue. Corresponding red clover production levels were 10.93 and 5.30 t DM ha^?1 (red clover swards), 8.04 and 3.131 ha^?1 (red clover-timothy), and 6.42 and 109 t ha^?1 (red clover-tall fescue). Total herbage organic matter digestibility was improved by the timothy companion grass but not consistently by the tall fescue, whereas crude protein (CP) concentration was decreased by the addition of either grass. Increased seed rate intensified these effects, as well as the general effect of the companion grass in depressing red clover DM, digestible organic matter (DOM) and CP production. Total herbage DM, DOM and CP were not markedly affected by increasing red clover seed rate but red clover DM, DOM and CP were increased as red clover seed rate was raised, due to increases in the red clover component. The potential for silage cropping of red clover swards was confirmed but there was advantage in sowing a companion grass. Taking yield and quality parameters into consideration, timothy proved a better companion than tall fescue. A seed rate of 2 or 4 kg ha^?1 timothy and 12 kg ha^?1 red clover proved the most satisfactory.     

Effect of agrochemical applied at sowing on seedling emergence and herbage yield of perennial ryegrass and white clover

Plots of white clover ( Trifolium repens ) and perennial ryegrass ( Lolium perenne ) white clover were sown with and without fungicide seed treatment, seed treatment with Cytozyme (a proprietary growth-promoting agent) and pesticide granules (carbofuran or carbosulfan) mixed with the seed. Sowings were made in April/May at Hurley (1986 and 1987), Dorchester (1987) and Bronydd Mawr (1987). Only treatments containing pesticide significantly improved seedling emergence or herbage yield in the 1986 sowing. In 1987, pesticide greatly increased seedling emergence of ryegrass and clover at Hurley and Dorchester, but had no effect at Bronydd Mawr. At Hurley, herbage yield and the proportion of clover were more than doubled for up to a year, by chemical treatment after sowing in 1986.
Populations of plant parasitic nematodes were recorded at all sites and it is suggested that at Hurley and Dorchester seedlings with nematode damage were unable to survive the dry soil conditions that prevailed. In a subsequent pot experiment, pesticide granules controlled root endoparasitic nematodes and significantly increased seedling emergence of white clover in dry soil but had no effect in moist soil.     

A COMPARISON OF THE REACTION OF DIFFERENT GRASS SPECIES TO FERTILIZER NITROGEN AND TO GROWTH IN ASSOCIATION WITH WHITE CLOVER

Seven species or varieties of grass, and a mixture of 3 of them, were sown in pure swards and treated with 4 levels of nitrogenous fertilizer (0,17·5, 35 and 70lb N per acre per cut). Each species, and the mixture, was also sown with white clover. The experiment was cut 4 or 5 times per year. The effect of fertilizer on the yield of each grass was compared with the effect of clover on the yield of the grass/clover swards. Mean annual yields showed an approximately linear response to N; there was a small but significant fall in response to the highest level of N. Response among the species ranged from 20 to 30 Ib of dry matter per Ib N applied for the intermediate level of fertilizer and from 14 to 23 Ib for the final increment of fertilizer.
S37 cocksfoot, S48 timothy, S24 ryegrass, and a mixture of these grasses, were high yielding and responded well to fertilizer N; Irish ryegrass and Agrostis tenuis were less productive and gave poorer responses to N. S215 meadow fescue and S23 ryegrass were intermediate in yield and response.
There were no significant differences between the annual yields of the 8 grass/clover mixtures; the yields of the grass and clover components of each mixture were inversely related. The effect of clover on the yield of the grass/clover mixtures was estimated to be equivalent to the effect of an annual application of 205 lb N per acre to Agrostis tenuis and 120 lb N to S48 timothy. The fluctuations in annual yields were greater with grass/ clover mixtures than with grass swards receiving N.
The yields of grasses when sown with clover were in similar order to their yields when sown pure; but whereas the latter tended to fall from year to year, the yields of the grass components of mixtures (except Irish ryegrass) did not.     

Herbage productivity of a range of grass species in association with white clover

Red fescue ( Festuca rubra L.) cvs Reptans, Dawson and Ruby, perennial ryegrass ( Lolium perenne L.) cvs Perma and Sprinter, crested dogstail ( Cynosurus cristatus L.) cv. Southlands, smooth meadow-grass ( Poa pratensis L.) cvs Parade and Arena, Yorkshire fog ( Holcus lanatus L.) commercial types I and II, creeping bent ( Agrostis stolonifera L.) cv. Penncross and rough meadow-grass ( Poa trivialis L.) cvs Omega Øtofte, Dasas and Sabre were each sown with white clover ( Trifolium repens L.) cv. Donna and the productivity of the fourteen mixtures assessed under simulated grazing (six harvests per year) for 3 years. A single fertilizer-N rate (50 kg ha⁻¹) in early spring was applied to all treatments each year.
Over the 3 years, mean annual dry matter (DM) production of the swards ranged from 5·25 t ha⁻¹ (creeping bent) to 8·71 t ha⁻¹ (red fescue cv. Reptans), with the species ranking order of: red fescue > perennial ryegrass > crested dogstail > smooth meadow-grass > Yorkshire fog > creeping bent. Rough meadow-grass only persisted over the first harvest year. Mean annual organic matter digestibility (OMD) values of the swards ranged from 0·712 (creeping bent) to 0·782 (ryegrass cv. Sprinter). Mixtures with the lowest proportion of grass (crested dogstail and smooth meadow-grass) generally gave the highest proportions of white clover. The creeping bent mixture had exceptionally low production of both components.
Red fescue, crested dogstail and smooth meadow-grass showed compatibility with clover and, therefore, have potential for use in grass/clover swards. Yorkshire fog had lower compatability with clover. Some breeding effort to improve selected characteristics of promising species, e.g. improvement of low OMD in red fescue, seems warranted.     

A STUDY IN METHODS OF GRASS VARIETY TESTING

Methods for the appraisal of varieties in forage grasses are examined in the light of results from an experiment. Five varieties of perennial ryegrass were grown as spaced plants, broadcast swards and swards with white clover, and all were subjected to five cutting treatments during the first and second harvest year.
Spaced plants and swards gave equally good information on the order in which varieties attained maximum rate of growth in spring each year; but in respect of actual yield, the order in which varieties were placed in spaced-plant culture was reversed in broadcast swards. It is suggested that the disparity may have arisen because all varieties were sown at a common seed rate; and that spaced-plant cultures give a better indication of relative potentialities than do the majority of sward trials.
Late-maturing varieties compared better with early varieties when each variety was cut with reference to date of ear emergence than when all varieties were cut simultaneously (that is, in respect of dry matter production: at a given stage of development the early varieties had a slightly higher nitrogen content than the late). The shortcomings of both systems of cutting, and the need for comprehensive tests, are discussed.
There was little interaction between method of culture and cutting treatment in this experiment.     

Effects of sowing date,placement of seed,vegetation suppression,slugs, and insects upon establishment of no-till alfalfa in orchardgrass sod†

Four treatments designed to affect some environmental factors during germination and establishment of alfalfa were: two sowing dates (March and May) to produce differences in temperature, light and soil moisture; two sowing methods (notill drill and hand sowing) for creating different degrees of soil-seed contact; mowing and banded and broadcast sprays of glyphosate to produce varying degrees of plant competition; and methiocarb bait combined with carbofuran granules vs. no pesticide to establish different levels of invertebrate feeding. Alfalfa dry matter (DM) production was affected very little by sowing date in two identical experiments. It was unaffacted by sowing method in experiment 1 (1983) but was significantly higher when alfalfa was sown with a drill in the second trial (1984). Highest alfalfa DM yields were achieved when competition was suppressed by broadcast spraying rather than bands, but details of effect differed in the two experiments. Pesticide treatments yielded more alfalfa DM in the year of establishment. Slugs, Deroceras leave (Müller) and D. reticulatum (Müller), and the potato leafhopper, Empoasca fabae (Harris), were among the potential pest species controlled and may have been partly responsible for the observed effects.